The last fine-sanding on the ports done:
http://htfhome.com/2007/e4/e4_209.jpg

Priming:
http://htfhome.com/2007/e4/e4_210.jpg

A layer of varnish on one of the bottom endcaps:
http://htfhome.com/2007/e4/e4_212.jpg

---

A little OT: To my joy, the PC speaker of my colleague is a ported system. Have you ever seen a cuter and smaller port? Its 15mm in diameter...:
http://htfhome.com/2007/e4/e4_213.jpg



The first layer of (spray) paint on one of the ports:
http://htfhome.com/2007/e4/e4_214.jpg
(its tricky to take good pictures of black things...)


Then one thing that I should have done long before I started with the painting (and would have, if I'd read ecir38's thread more closely...), drilling leg holes in the bottom plate that matches the bottom endcap:
http://htfhome.com/2007/e4/e4_216.jpg
(as you can see I've got a nasty gangrene on my left hand - it's a tough life up here in icy Norway :p )

To be continued...

...continued.

Standing nicely in the paint queue:
http://htfhome.com/2007/e4/e4_217.jpg

After the painting:
http://htfhome.com/2007/e4/e4_218.jpg
(Just one more layer of varnish and the top encaps are more or less done :) )

Yes! Finally I get to put on the legs:
http://htfhome.com/2007/e4/e4_219.jpg
(in the background is my cave where I write this stuff. You can see another DIY-project - the PC-speakers with Infinity EMIT tweeters from a couple of 6x9 car speakers...)

All legs in place...:
http://htfhome.com/2007/e4/e4_220.jpg

..and most equally long:
http://htfhome.com/2007/e4/e4_221.jpg
(they'll all be screwed to the bottom plate anyway, so it's not a big deal)

To be continued...

Holy moly Rune, this is excellent work! I guess the only question left is when are you hoppin' over here to Canada to make mine for me?????

;)

...continued.

Cable time! Now it's time for making the cable between the Speakon socket and the driver. After countless hours of research I finally went for the fabled Audio Technica AT527, one of the worlds best high current cables for subwoofers:
http://htfhome.com/2007/e4/e4_222.jpg
(or maybe it just was the first cable I found when I put my hand in my heap of old cables. Take a guess... ;) )

Here the soldering is finished and a couple of more or less successfully places heat-shrinkable tubings in place:
http://htfhome.com/2007/e4/e4_224.jpg
(the head spread through the cable and made them almost too tight to move down again... :confused: )

Two finished cables:
http://htfhome.com/2007/e4/e4_225.jpg

Yeah! The cable fits in the smaller backside of the Speakon hole:
http://htfhome.com/2007/e4/e4_226.jpg

And here's how the Speakon socket looks on the finished bottom endcap:
http://htfhome.com/2007/e4/e4_227.jpg

Hope this wasn't an image overlaod for you guys ;)

Keep up the good work. I want to see those bad boys finished and rocking out!

looking really nice Rune....you european boys don't fuk around with good work, do ya! :D

Very impressive craftsmanship - those port flares look excellent!

Rune,
I've also got to say, excellent craftsmanship! You may be taking your time to make these, but they'll be a work of art when they're finished. :cool: What kind of paint setup are you using to do your painting? It looks very professional. As always, love the pics! :D

Craigo

Keep up the good work. I want to see those bad boys finished and rocking out!

Me to! We're talking mere weeks now...

looking really nice Rune....you european boys don't fuk around with good work, do ya! :D

Thanks man! Am I going to finish before you after all? You should be done by now ;-)

Very impressive craftsmanship - those port flares look excellent!

Thanks Steve! I take my time. Since my HT ain't finished there's no haste, and I can use more time on the details...

Rune,
I've also got to say, excellent craftsmanship! You may be taking your time to make these, but they'll be a work of art when they're finished. :cool: What kind of paint setup are you using to do your painting? It looks very professional. As always, love the pics! :D

Craigo

Thank you so much. As always, all you nice comments sure push med on. Thank you!

For the finish I use spray cans. First a layer or two with something called "sanding primer" (the middle can), which i sand down with 240 paper, then a layer (or two) of matte black (left can), before applying a layer (or two) with matte varnish (can to the right). I've used about two of each can so far.

http://htfhome.com/2007/e4/e4_235.jpg

The Speakon connector in place:
http://htfhome.com/2007/e4/e4_230.jpg


And with the plug attached:
http://htfhome.com/2007/e4/e4_231.jpg


To prevent any chance of leakage, the backside was sealed:
http://htfhome.com/2007/e4/e4_233.jpg


Time to paint he PVC-tube black a little further down than could be reached with the spray paint:
http://htfhome.com/2007/e4/e4_240.jpg


And this is a close-up of the port with the dried varnish (and not yet dried black paint a bit into the tube:
http://htfhome.com/2007/e4/e4_237.jpg
(the paint will be blacker when it dries)

So for a really tedious job. Due to my amateurish work with the spray can, some unpainted spots was left in the groove for the DIY port grille.
http://htfhome.com/2007/e4/e4_238.jpg
(I used one of my wifes paint brushes, which I, when I think of it, forgot to clean :eek: Time to write my will. Who wants the subs? :D )

The days work:
http://htfhome.com/2007/e4/e4_239.jpg
(poor Erna2 (my previous HTF sub and 3 sub projects since) is reduced to a life as a shelf)

man....you are really starting to impress me Rune...good job bro. The feet came out really clean, and attention to detail is very good. excellent job. Hopefully mine will be as good :)

http://htfhome.com/2007/e4/e4_238.jpg

That's just sick man, ain't nobody gonna see in there!!! :D

Hmmm, I'll bet you've never been called a perfectionist. :D

Thanks for the information on the paint. You're getting great results with that process.

Hey that's a new use of Bob the Builder train track. I'll have to remember that one. I think my son still might have some laying around.

Craigo

That's just sick man, ain't nobody gonna see in there!!! :D

Hehe - that depends on for how long the port grille stays in place when the sub really starts moving some air, won't it? :D

man....you are really starting to impress me Rune...good job bro. The feet came out really clean, and attention to detail is very good. excellent job. Hopefully mine will be as good :)

I'm sure they will be!

BTW: I'm starving for more reports from your side!

BTW: I'm starving for more reports from your side!

working on it brother...working on it. I'm doing sanding and sealing this weekend.

wife + 2 kids, 10-12 hour work days, submittal of 3 patents in 4 weeks, and family matters, leave only so much time for doing these subs....but they'll get done soon, dont worry. ;)

Hmmm, I'll bet you've never been called a perfectionist. :D

Well, actually, no... But this project has become something special...

Hey that's a new use of Bob the Builder train track. I'll have to remember that one. I think my son still might have some laying around.

Craigo

Hehehe - so you noticed it, did you?

Tonight I did the top endcaps:

First 70 mm whatever-you-call-it (wall insulation):
http://htfhome.com/2007/e4/e4_242.jpg

Then 30mm acoustic wave-foam:
http://htfhome.com/2007/e4/e4_243.jpg

Trying the cutouts on a piece of PVC-tube:
http://htfhome.com/2007/e4/e4_244.jpg

The whole this is to be covered by some fabric to eliminate any particles from being blown around in the sub and out in the room. My wife's storage of fabric peices was searched for a suitable piece of fabric:

What the.... it's only flowers here:
http://htfhome.com/2007/e4/e4_245.jpg

This particular one was under brief consideration - not:
http://htfhome.com/2007/e4/e4_246.jpg

Finally I found a piece of fabric that I could use and still show myself here on the forum:
http://htfhome.com/2007/e4/e4_247.jpg

To be continued...

...countinued.

I guess I'm the first one to show a port tube with skirt around here:
http://htfhome.com/2007/e4/e4_248.jpg

This tape react chemically with itself so it becomes a rubber substance that never lets go:
http://htfhome.com/2007/e4/e4_249.jpg

Fastening the outside of the fabric:
http://htfhome.com/2007/e4/e4_250.jpg

And here are the top endcaps with the lining finished:
http://htfhome.com/2007/e4/e4_251.jpg
It's not all the way to the outer edge of the endcap, because I'm also going to line the inside of the tube.

The two top endcaps:
http://htfhome.com/2007/e4/e4_252.jpg


To do:

- Line the tubes
- Put on the DIY-flares
- Put together the contraptions

Crazy! 1) I've never seen anyone line their endcaps with dampening material; and 2) I've never seen such a sexy port tube in a skirt!

WOOT!

That endcap dampening is seriously nice work!

That endcap dampening is seriously nice work!

I'm glad to hear I made the right decision scrapping the flowers... :D

The tube was placed on the freezer for a better work height:
http://htfhome.com/2007/e4/e4_253.jpg
(I think it's cute)

The top endcap goes about 50mm into the tube, so the foam is placed accordingly:
http://htfhome.com/2007/e4/e4_254.jpg

What's all this talk about glue? These things don't move even without glue:
http://htfhome.com/2007/e4/e4_255.jpg

Using some contact cement in the corners anyway:
http://htfhome.com/2007/e4/e4_256.jpg
(better safe than sorry)

One tube finished:
http://htfhome.com/2007/e4/e4_258.jpg

Nope, not the other one unfortunately. It's the same from another angle...:
http://htfhome.com/2007/e4/e4_259.jpg

One tube to go. Then glue on some carpet and only the assembly is left.

Looks Great! I cant wait to read your thoughts on its sound. :D

Looks Great! I cant wait to read your thoughts on its sound. :D

Thanks!

I can't wait either, although I have to admit that I have few references when it comes to really good subs, so I don't know exactly how I shall judge/compare it...

Thanks!

I can't wait either, although I have to admit that I have few references when it comes to really good subs, so I don't know exactly how I shall judge/compare it...

I was in the same situation. I think you'll find that from now on, you'll be spoiled. Friends will be blown away and you will think, "Man, is there any other way to do it?". Now I don't mean that as far as alignment is concerned, but rather DIY vs Commercial.

I too , await your final finished pics and impressions. I forgot, did you break in the drivers some?

I was in the same situation. I think you'll find that from now on, you'll be spoiled. Friends will be blown away and you will think, "Man, is there any other way to do it?".

I too , await your final finished pics and impressions. I forgot, did you break in the drivers some?

I did some light break in in free air for about 40 hours or so, but I don't know if it had any real effect...

Here's some pictures of the carpet that I'll use to dress my tubes:

http://home.online.no/~bleivik/IMG_0296.jpg

http://home.online.no/~bleivik/IMG_0292.jpg

http://home.online.no/~bleivik/IMG_0293.jpg

I guess it's what's called "automotive carpet" or something similar. It consists of two parts. One 2mm hard (grey) part and one 3mm softer (black) part.

That is PERFECT carpeting for subs. Where can I get stuff like that??

That is PERFECT carpeting for subs. Where can I get stuff like that??

I have no friggin idea where to get it in the States... it was bought in a more-or-less normal carpet shop (who also sells paint etc.).

It looks like standard automotive carpet to me.

Time to make some speaker cables!
(sorry about the bad pics! My wife run off with my camera this weekend, so I had to use the cell phone camera...)


Speakon in both ends so that they plug into both the amp and the subs:
http://htfhome.com/2007/e4/e4_269.jpg

The Speakon conenctor supports max 4 sq mm cables, so I had to take away a few strands:
http://htfhome.com/2007/e4/e4_270.jpg

On with the heat-shrinkable tubings:
http://htfhome.com/2007/e4/e4_271.jpg

The finished product - two 8 meter cables:
http://htfhome.com/2007/e4/e4_274.jpg

Why 8 meters? It's for the HTF thing. We're using quite a large room and don't know the exact posision of the subs.

The base plates was actually more or less done (except for the painting), but then the mirror idea came up, and I had to make some adjustments.

Instead of recessing the mirrors, I "built up" the rest of the base plate with a 5mm thick (same as mirror) material:
http://htfhome.com/2007/e4/e4_276.jpg
(here I'm using the router to cut them out)

Here's how the baseplate sans mirror will look like:
http://htfhome.com/2007/e4/e4_277.jpg

The old story about the glue and the clamps:
http://htfhome.com/2007/e4/e4_278.jpg

I was stupid enough to round both the upper and lower edge of the base plates. The upper edge should never have been rounded, because when I added the 5mm material I got a groove that had to be filled:
http://htfhome.com/2007/e4/e4_279.jpg
(a bit strange focus, but I'm trying to show the profile)

First one round with two component filler (because the usual one shrinks a little):
http://htfhome.com/2007/e4/e4_280.jpg

Then one round with normal filler:
http://htfhome.com/2007/e4/e4_281.jpg

Ah! Finally I could do the routing and make the rounding that was intended in the first place:
http://htfhome.com/2007/e4/e4_283.jpg

Cool pics man, they came out great for a cell phone camera!!!

dude...I need to get YOUR cell phone camera! :eek:

mine comes out like stir fried sh!t in comparison! :(

excellent job as always!

Cool pics man, they came out great for a cell phone camera!!!

It's from a Sony Ericsson W810i. It's the standard 2 mpix camera that is in half of the SE phones I think...

I guess they're allright... Would've been better if I could have attached it properly to a tripod, though...

To get the most out of the cell phone camera, the same rules apply as with the pocket camera:

1. Use tripod
2. Don't use flash

On the cell phone camera menu I used the "nigh mode" which means that it uses a long exposure time instead of a flash. In addition it actually had a macro mode (nice for those close-ups). Due to the long exposure time it was a must to hold the cell phone still for a few seconds. I rested it on the top of the tripod, but was unable to attach it.

dude...I need to get YOUR cell phone camera! :eek:

mine comes out like stir fried sh!t in comparison! :(

excellent job as always!

Hehe - I'll swap it for your subs ;-)

Maybe your pics are fuzzy, but at least you consentrate on finishing your subs instead of messing around taking the best possible pictures...

Keep up the good work!

What material dd you use for that buildup? Is it going to finish as well as MDF?

What material dd you use for that buildup? Is it going to finish as well as MDF?

I think it's called huntonit or something. It's coarse on one side and smooth on the other. I have no idea how it'll finish. I'm not worried though, as the bottom plate is an easy part to replace if the finish turns out to be a disaster ;)

I'm about ready for carpeting the tubes now. But first I have a job to do in my work room.

Behold da mess:
http://htfhome.com/2007/e4/e4_284.jpg
(to put it this way: I'm not walking around here barefoot ;) )

I have to clean this incredible mess up, before I can start wrapping the carpet around the tubes (by lying the carpet on the floor and rolling the tube over it).

Wish me good luck...

Damn Rune, it's going to take you another week to clean up that mess! :D

Actually, I had noticed that your shop was getting a bit cluttered in one of the more recent pics. My woodshop doubles as a garage. Consequently I'm regularly dusting off my sons bike and helmet before he goes for a ride.

Good to see your on the home stretch. Keep it up. Looking forward to the final pics and first impressions.

Craigo

Nah... much was done in one night:
http://htfhome.com/2007/e4/e4_285.jpg

I think the MDF dust alone amounted to two whole plastic sacks. I think I've done 35 rounds with the router per sub (and that's not counting multiple passes and extra rounds because of errors).

Is it any wonder there's some dust?

Plastic on the floor makes it clean enough:
http://htfhome.com/2007/e4/e4_286.jpg

First I cut the 200 x 306 cm carpet in two:
http://htfhome.com/2007/e4/e4_287.jpg

Then I rolled it around one tube to align it properly:
http://htfhome.com/2007/e4/e4_288.jpg

Then I gently pulled back a piece of carpet and sprayed it ,and the corresponding part of the tube, with glue:
http://htfhome.com/2007/e4/e4_289.jpg

Note that I left a 15cm gap against the end of the carpet. After 15-20 minutes I rolled the tube over the glued part and then the direction of the tube/carpet was locked.

Then it's only a matter of glueing the rest (almost)...:
http://htfhome.com/2007/e4/e4_290.jpg

...and roll on:
http://htfhome.com/2007/e4/e4_291.jpg

As I wrote before, I've left 15 cm towards the carpet joint unglued. This is to be able to "double-cut" them (to make a nice joint).

As I wrote before, I've left 15 cm towards the carpet joint unglued. This is to be able to "double-cut" them (to make a nice joint).
So what are you going to use as backwall when doing the doublecut so as to not cut through the tube?

So what are you going to use as backwall when doing the doublecut so as to not cut through the tube?

Good question, ssabripo! The best would undoubtedly have been some kind of thin sheet of metal (thin to not make the carpet ends too long and of metal so you don't cut through it).

I'm not sure how to obtain such a piece of metal, so I think I'll settle for something called "rettepapp" - well it's called "rettepapp" in Norway anyway... :D

I haven't the faintest idea what it's called in English, but it's basically precut cardboard strips used in construction to get those last two millimeters right. I have used it a lot when refurbishing my home (to get some walls straight(er)).

The strips are about 2 x 1000 x 50 (or 1 x 1000 x 50) millimeters, and even if they certainly are not "cut proof", I'll think a couple of those taped together lengthwise should do the trick.

What do you think?

Sherv/Rune - I found that with a good really sharp blade, one doesn't have to worry about doing much of anything to the tube. It is much stiffer/stronger than the carpet.

Or you can use a hook blade, like this:

http://www.amazon.com/Stanley-11-983-5-Pack-Large-Blade/dp/B00002X20T

I did mine like willy, change the blade three or four times if you have to and just take your time. A good straight edge to work of off would be nice too.

http://i61.photobucket.com/albums/h69/ecir38/LLT/31-1.jpg

Sherv/Rune - I found that with a good really sharp blade, one doesn't have to worry about doing much of anything to the tube. It is much stiffer/stronger than the carpet.

Or you can use a hook blade, like this:

http://www.amazon.com/Stanley-11-983-5-Pack-Large-Blade/dp/B00002X20T

I'll take your word for it, but I haven't got my lazy ass to a store that has this kind of blade yet...

I did mine like willy, change the blade three or four times if you have to and just take your time. A good straight edge to work of off would be nice too.

http://i61.photobucket.com/albums/h69/ecir38/LLT/31-1.jpg

I keep imaging that if you use a hook blade (and have to change blade 2-3 times for one length of double-cut), the cut must become rough/edgy?

But again, since I don't have a hook blade and I'm dying to get the sub done, I'll try with the standard (stanley?) knife cut approach.

Then you two can do the what-did-I-say-routine when I fail miserably ;)

BTW: I envy your metal ruler! Looks really nice for that purpose. I'll have to use a "long water" to do the same.

Rune, i didn't use the hook type, i just use a regular blade.

Rune, i didn't use the hook type, i just use a regular blade.

Neither did I, I just wanted to point out that it is a good option.

More importantly, you just want a really sharp blade. :)

Rune, i didn't use the hook type, i just use a regular blade.

Neither did I, I just wanted to point out that it is a good option.

You guys...

Well, I've done one tube, with mixed luck I'll have to say. But it turned out OK in the end (I think). I'll write more about it tomorrow (with some pics).

Mine came out good but still not perfect. Anyway the good thing is that is on the back. Even if it was on the front with that type of carpet i'm sure it wouldn't be to noticable from a couple feet away.

I didn't find what I was looking for to protect the tube when cutting the carpet, so I had to use pieces of an old roll of cardboard/thick paper:
http://htfhome.com/2007/e4/e4_293.jpg
(at least it had the right rounding from being rolled up ;) )

Then I placed it on the tube and then placed the two carpet ends nicely over each other - and did the doubel cut:
http://htfhome.com/2007/e4/e4_294.jpg

Horror of horrors!

Waining! This is NOT the perfect way of doing this. It turned out that doing it this way made the carpet ends overlapping with 1-2mm. My guess is that there could be a few reasons for this:

1. The protective cardboard increased the diameter (and thus the carpet length)
2. The thickness of the carpet itself increased the diameter (and thus the carpet length)
3. I didn't make the carpet ends taut enough before cutting

Exactly which of the above that was the reason I don't know. Probably a combination...

Anyway. The result was that I had to go to Plan 10 (from outer sapce) - almost as bad as Plan 9...:
http://htfhome.com/2007/e4/e4_295.jpg
Well, it wasn't too bad, actually. Taking off 1-2 mm along the carpet edge turned out to work ok. Not perfectly in any way, but ok. Please note the reddish colour of my skin as I became quite hot when I discovered the 1-2mm overlap (and pretty desperate).

But here's the result anyway:
http://htfhome.com/2007/e4/e4_297.jpg
Before you all go "but that's a fantastic result!" I have to inform you that the carpet joint is much more visible in real life than in the picture. Most of the joint is good, but there are patches where the carpet ends doesn't completely meet and has a gap of about 1 mm. But because I pre-painted the tubes black, it isn't too visible.

But I'm glad the subs are to be placed against a wall and not in the center of the room... ;)

For sub #2 I'll do it a little bit differently: I'll won't do a double cut, but make two marks on the tube, then place the ruler according to these and cut first one, then the other end of the carpet. In this way, problem 2 and 3 (which are the worst) on the problem list above will be eliminated. I'll report the results when they are ready!


Well, well. Life goes on. The top/bottom ends of the carpet are cut:
http://htfhome.com/2007/e4/e4_298.jpg

Here's the result:
http://htfhome.com/2007/e4/e4_299.jpg

Now with the carpet in place, I can see the end of the tunnel! I just had to dry-try the bottom endcap. With the minor setback of the carpeting, it was a really nice feeling to pop in the endcap. I didn't have to use much force, but I had to circle around and "bump" it lower and lower with my fist. Nice feeling!
http://htfhome.com/2007/e4/e4_300.jpg
BTW: This was picture #300 in this thread...

A detail of the bottom endcap:
http://htfhome.com/2007/e4/e4_301.jpg

Just the rest left!

You're so close!

DAYUM!......oh, so close.....Powering up in ten, nine, eight, seven.......

:D

DAYUM!......oh, so close.....Powering up in ten, nine, eight, seven.......

:D
.....Houston, we have a problem. :D

Nice work & documentation!

Excellent Rune! Just seeing those latest pics put a big smile on my face. :D Very happy for you. You've done a great job on these subs and I'm sure you'll be amply rewarded when it's all said and done.

Here's an idea I had for cutting that carpet more accurately. I can't say this works from experience, but you should be able to test it before making the final cut. Try cutting one edge with a sheet rock T-square or with your straight edge clamped to the tube as you did before. Then wrap the carpet around the tube, and mark the position of the opposite edge with a small cut on the carpet at both ends. Double check the fit and when you're reasonably sure you've matched it up, lay the carpet out flat, clamp your straight edge to the carpet using the cuts for guides, and cut it. As long as you can keep your knife perpendicular to the carpet, you should get a nice clean cut.

Craigo

If your end caps went in pretty easily, you'll definitely wan to make sure you seal them with some caulk when you're all done. Looks great!

Nice work & documentation!

Thanks :)

Excellent Rune! Just seeing those latest pics put a big smile on my face. :D Very happy for you. You've done a great job on these subs and I'm sure you'll be amply rewarded when it's all said and done.

Here's an idea I had for cutting that carpet more accurately. I can't say this works from experience, but you should be able to test it before making the final cut. Try cutting one edge with a sheet rock T-square or with your straight edge clamped to the tube as you did before. Then wrap the carpet around the tube, and mark the position of the opposite edge with a small cut on the carpet at both ends. Double check the fit and when you're reasonably sure you've matched it up, lay the carpet out flat, clamp your straight edge to the carpet using the cuts for guides, and cut it. As long as you can keep your knife perpendicular to the carpet, you should get a nice clean cut.

Craigo

Thanks for the nice words, Craigo!

I'm not familiar with "sheet rock T-square". Could you please explain?

If your end caps went in pretty easily, you'll definitely wan to make sure you seal them with some caulk when you're all done. Looks great!

Steve, I'll tell you about the tightness of my top endcap tomorrow, but lemme tell you one thing now. The only thing to get that (¤/&¤%%&( thing down was with this:

http://htfhome.com/2007/e4/e4_306.jpg

Yesterday I was supposed to assemble tube #1. The bottom endcap had a fairly tight fit. That means that it was relatively easy to get it into the tube with my bare hands (by knocking it down, going around it in circles). It wasn't a very tight fit so I added a thin film of glue around the tube before I plugged it in.

Heres a close-up of the bottom endcap grove vs carpet:
http://htfhome.com/2007/e4/e4_302.jpg

Time for the top endcaps. I glued on the DIY-flares that I have had so much fun with (and used so many hours on...):
http://htfhome.com/2007/e4/e4_303.jpg

Yet another moment of truth... There have been a lot of those lately, but this one was the mother of all moments of thruth, I'll tell you! The to endcap ready for plugging:
http://htfhome.com/2007/e4/e4_304.jpg
(the picture lies a little bit as it's not as light as the image says)

A last check that there are nothing that juts out to hinder the plugging. Looks good:
http://htfhome.com/2007/e4/e4_305.jpg

I had dry assembled the top endcap once before. Well, I only went half the way, but it went smoothly (I used no tools). Therefore I assumed that this was a little bit too loose fit, so here too I glued the tube.

Some of you guys keep telling me that if the fit is tight enough, I don't need glue. Well, to make a long story short, I could have spared me the glue...

The first half of the top endcap went in smoothly as before, but suddenly, the sound when I used my fist to "hammer" it down chanced, and that is not a good sign... The endcap was stuck!!! :eek:

:eek: NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO ! :eek:

It was absolutely no way that the damned thing would move, so I just had to use some tougher tools - like a small sledgehammer. First I tried with a light rap - no movement! Then a medium rap - no movement!

OK, f**k it, I thought, this is "sink or swim" and hit the thing with 80% force, and yes, it moved a mm or two! I did the same in rounds, and lo and behold, the thing actually went in all the way...

One thing is for sure - this thing will NEVER come off again....

---

Well, theres nothing that a sledgehammer and a box of Valium cannot fix :D

You've seen this picture before, but here's the "fine tool" that I used to get the top endcap down:
http://htfhome.com/2007/e4/e4_306.jpg
(amazingly, neither the top endcap nor the tube was damaged in the process)

And here it is:
http://htfhome.com/2007/e4/e4_307.jpg
(the driver and the base plate is not in place yet)

#2 is "under carpeting" so it'll get there soon. I know for a fact that the other top endcap has a much looser fit, so I'm hoping to avoid this nightmare the next time.

-Rune

My god Rune, I can GUARANTEE that I will be hammering my end caps in for sure! LOL! If it happened to you, with your skilz, its going to happen 10x worse for me, LOL!!!

Sheet-rock T-square is just a drywall T-square. All it is is a BIG T-square that is usually metal, VERY straight, and awesome for lining things up for cutting.

My god Rune, I can GUARANTEE that I will be hammering my end caps in for sure! LOL! If it happened to you, with your skilz, its going to happen 10x worse for me, LOL!!!

Hehe - thanks for the confidence in my skills, but I assure you, the fact that I work slow doesn't necessarily mean that I'm skilled - I'd say it's the other way around... ;)

I think you'll do just fine - just remember to put the endcaps a little further into the tubes before declaring them done. My wild guess is that the two discs of 22mm MDF wasn't lined up 100% and that the top endcap got stuck between those two.

The misalignment must have been really microscopic, though, because I couldn't feel it.

If I should make another sonosub, I think I'd make a small pass with the roundover bit on the upper disc so that the danger of getting stuck between the two was eliminated.

Sheet-rock T-square is just a drywall T-square. All it is is a BIG T-square that is usually metal, VERY straight, and awesome for lining things up for cutting.


Actually, it was the "T-square" term that I was not familiar with, but after some googling I guess this is what you mean:

http://www.pearlpaint.com/include/images_inc~fName~pics_products%5C102176.jpg~width~300~height ~400.htm

Hmmm... I think I'll have to get me one of those. I can certainly see many uses for it. Thanks for the tip!

Last night I tried one of the tubes for the first time!

Unfortunately I haven't any decent systemt to try them on... Basically, I was only able to check if there was any sound or not, by hooking up a CD Walkman with a CD-R directly to the Behringer. On the CD-R was a song that was LP-filtered at 100Hz with CoolEdit2.0. Not much of a test as I said. The line output levels from the CD Walkman was obviously too low for the PA amp, so nothing too much happened...

One thing I noticed though, was that even at relatively low levels I could clearly feel the vibrations on the side of the tube... :confused:

How common is this and what happens when things really starts happening?

It is almost a miracle that just 5mm thickness of the sonotube can be enough - is it too good to be true?

As I said, I really haven't tested it thoroughly yet.

FINALLY I got the driver installed into one of the subs:

After some tries, I found this position to be the best for installing the (less than cooperative) driver:
http://htfhome.com/2007/e4/e4_308.jpg

I put a screw through the uppermost hole in the dirver. Then I rested the lower part of the driver on the bottom endcap while lowering the (upper part of) driver towards the sub and trying to hit the pre-drilled hole with the screw.

Maybe a clumsy way of doing it - but I was a lone and the driver was heavy... :o


A couple of more pics:
http://htfhome.com/2007/e4/e4_309.jpg

http://htfhome.com/2007/e4/e4_310.jpg

I've only done the most brief of tests of the sub, but that is goes deep down there is without doubt. I was supposed to use REW 4.0 for the testing, but I just couldn't get it to work...

Cool.

Nice work. My sub doesn't really vibrate much, even at 100db+ levels....I'm thinking what you experienced might be because the baseplate wasn't on and any slight vibration was exaggerated by the legs on the floor as opposed to spreading the energy over a much large base? :confused: This is assuming the baseplate wasn't attached yet.

Nice work. My sub doesn't really vibrate much, even at 100db+ levels....I'm thinking what you experienced might be because the baseplate wasn't on and any slight vibration was exaggerated by the legs on the floor as opposed to spreading the energy over a much large base? :confused: This is assuming the baseplate wasn't attached yet.

It wasn't. And I think maybe I was feeling vertical vibrations, because it felt the same all over the sub. If it was horizontal vibrations, I gues it would have been most pronounced on the middle?

Anyway I've found the resonant frequency of my basement floor to be 35 Hz and that if you go low enough, you acn actually see the movement (htfhome.com/2007/e4/Erna@10Hz.avi) of the driver - on the analogue SPL meter :D

Yes, I'm careful below the tuning frequency. As you can see from the video the driver is just humming along.

Man, those TC2000 look so nice!

Man, those TC2000 look so nice!

Yes, indeed they do!

Sorry for not keeping you updated, but I'm on a sub-break. I'll come back when I've got something of interest to report...

Right now, I'm just finishing the base plates. Not very interesting....

Hey Rune,

Sorry I didn't get in to reply to the question about the T-square. I see someone else helped you out. I was on a weekend vacation so missed things for a few days. Looking good dude.

Craigo

I finally got off my butt and carpeted the other tube. The last time the carpet ends ended up 2-3mm too long. Hoping to avoid this on the second tube I followed this list of actions:

1. I did two single cuts instead of a double cut to avoid the "larger radius"-problem
2. I used a thinner "tube-protector" material (platic this time) to avoid the "larger radius"-problem
3. I paid special attention to tightening the carpet before cutting

Instead of doing a double cut, I market the sub with a very small cut with the knife:
http://www.htfhome.com/2007/e4/e4_312.jpg

On the second cut (which I did on the same side if the ruler), the ruler was adjusted to the markings on the tube:
http://www.htfhome.com/2007/e4/e4_313.jpg

Since I used the same side of the ruler for the two cuts, and was very accurate (or at least tried to), I was pretty sure that time it would be close to perfect.

Not so!

After all these precautions, there still was 1-2mm overlap! Why? The only thing that I can think of is that the carpet wasn't tight enough while cutting. Well, it's not easy to do this when you're alone...

Anyway, by cutting the edge of the carpet at an edge, the small overlap become manageable:
http://www.htfhome.com/2007/e4/e4_317.jpg
(this is the left carpet end, bent up so that the cut on the underside is visible)

Not perfect, but better than the fisrt try:
http://www.htfhome.com/2007/e4/e4_318.jpg

From another angle:
http://www.htfhome.com/2007/e4/e4_319.jpg

---

Have also started the painting of the base plates:
http://www.htfhome.com/2007/e4/e4_315.jpg

As always, they look the most impressive when the spray paint is still not dry:
http://www.htfhome.com/2007/e4/e4_316.jpg


Just as when I wash my car.

As ssabripo, I've also made a very early measurement of my sonos (well, actually only the one I'm finished with), and lo and behold - I have also a rather nasty dip in the 25-38 Hz area!!!

http://avforum.no/forum/attachments/diy-do-yourself/17220d1171799407-tc-2000-sonosub-rune_sono.gif

The top at 40-50 Hz can be attributed to room modes I guess (my room is 6.68 x 4.14 x 2.4 meters if that means anything to you guys), but the -12dB dip at 26-38 Hz really bothers me, as don't recognize this frequency in any of the Room Mode calculators I've used.

I sure hope it was the sloppy measurement setup :o that lead to these numbers ( the sub was placed in the middle of the room, and the SPL meter was actually placed in the next room (but right outside the doorway), because thats how far the cable went...).

Hi Rune,

How did you make the FR measurement? You might be able to rule out room modes by taking measurements in several places around the room. The peaks and dips caused by resonances will vary a lot across the room. The dip is really close to the the half wavelength of the 6.68m mode (~25 Hz). This mode will have a null in the center of the room and maxima in the corners.

Cheers,
Mike

Rune - I really wouldn't pay much attention to a FR measurement taken with the sub in the middle of the room and the meter not in the listening position. It really isn't representative of what you'll see when both subs are in their final resting place, and you take the measurements from the listening position.

IMO, anyway.

Hi Rune,

How did you make the FR measurement? You might be able to rule out room modes by taking measurements in several places around the room. The peaks and dips caused by resonances will vary a lot across the room. The dip is really close to the the half wavelength of the 6.68m mode (~25 Hz). This mode will have a null in the center of the room and maxima in the corners.

Cheers,
Mike

As I wrote, my measurement method was really, REALLY not very thorough. I did the measuring at ONE place in the room, and the sub was placed in the middle of the room. I just played sines (generated with the tone generator in REW with a 5Hz interval). I didn't have the correction tables for the Radio Shack SPL meter at hand, so my measurement frequencies didn't quite match. But I guess that's a minor issue compared to the -12 db@30Hz thing...

I'm quite confident that that dip can be reduced/eliminated with another placement.

Rune - I really wouldn't pay much attention to a FR measurement taken with the sub in the middle of the room and the meter not in the listening position. It really isn't representative of what you'll see when both subs are in their final resting place, and you take the measurements from the listening position.

IMO, anyway.

Good to hear, Willd. I'll try to make an outdoor measurement as soon as the snow has gone... Then we'll really get some answers.

Before dragging it outside, a close mic FR sweep of the driver using RoomEQ Wizard with the proper correction file will basically tell you everything you need to know. Place the mic or spl meter a few inches away from the driver and do a 10-100hz sweep at ~75db.

Before dragging it outside, a close mic FR sweep of the driver using RoomEQ Wizard with the proper correction file will basically tell you everything you need to know. Place the mic or spl meter a few inches away from the driver and do a 10-100hz sweep at ~75db.

Thanks Steve. I'll do that.

So Rune, how have the subs been?

So Rune, how have the subs been?

Hi again!

I've been on a vacation in the Norwegian mountains lately. This week we celebrate our sons 4th birthday etc...

In short - I haven't been working on/testing them. They're still there, however, and I'll finish them soon enugh. I've got one layer of varnish on the base plates left, and then they're done.

I'm a little afraid to test them, though, considering the story of their larger twin brothers...

I bet that was a nice vacation!

I bet that was a nice vacation!

Yup. This (http://www.gaustablikk.no/index.jsp?SDP_CHANGE_USERLANG=en) is the place...

Hi there again!

After a few of the usual kid induced local catastrophes (like my 2.5 yr daughter playing with water in the second floor bathroom until my son announced that it was "raining in the kitchen" (which happens to be the room below)), I've finally done some work on the subs again.

SteveCallas adviced me to make a "near field" measurement of the sub (SPL meter close to the driver) to lessen the impact of room modes, so that's what I did:
http://www.htfhome.com/2007/e4/e4_333.jpg

And here's the curve from REW:
http://www.htfhome.com/2007/e4/e4_334.jpg

I think we're onto something now...

Why the increase from 100 to 10 Hz? I have no idea. I'm a total idiot when it comes to a lot of things, and REW in particular. I have no idea if this is room gain or some kind of house curve thingie... I sure hope somebody know...;-)

Something is wrong with your measurement. It shouldn't look like that.

Yeah, a 12db rise from 50-10hz on a close mic sweep means something is off. I just saw something similar at the Shack and I had done something a little similar myself the first time I took measurements. It has to do with your soundcard correction file - some soundcards have a naturally rising low end. Either you skipped making a correction file or you made it but it isn't being applied correctly.

Also, while it's nice to stay safe during sine waves and sweep testing like this, you can definitely test a bit louder than that ;) Typically these kinds of tests are done at 75db or louder.

That looks like random noise. Check your sound card/REW settings, check that you're recording the correct channel.

What kind of sound card you have?

I have never used the SPL meter in that way. Does the output give the entire signal range or just the range the meter is set to?

Yeah, a 12db rise from 50-10hz on a close mic sweep means something is off. I just saw something similar at the Shack and I had done something a little similar myself the first time I took measurements. It has to do with your soundcard correction file - some soundcards have a naturally rising low end. Either you skipped making a correction file or you made it but it isn't being applied correctly.

Also, while it's nice to stay safe during sine waves and sweep testing like this, you can definitely test a bit louder than that ;) Typically these kinds of tests are done at 75db or louder.

My wife and kids were sleeping, that's why I kept it so low...

As for the random noise - I trust you guys when you say something is wrong here. I cannot get the hang og REW so I've probably done something horribly wrong.

I'm pretty sure I've calibrated the soundcard (not that it needed much calibration in the first place, as it was +/- 1dB from 5 Hz to 20kHz or so).

So what am I doing wrong? I have no idea... I'm starting to suspect that the LINE OUT of my SPL meter is broken.

Arrrrrrgh!

That looks like random noise. Check your sound card/REW settings, check that you're recording the correct channel.

What kind of sound card you have?


I'll double check the channel later on. If it's something as simple (and dumb) as that, I'll go stick my head in the port and play something really nasty on the sub...

As for the type of soundcard, it's a Creative SB Connect, Optical Digital I/O:

http://www.komplett.no/img/p/400/327240.jpg

Seems like an all right card to me. At least it was surprisingly linear when I calibrated it.

Ok, so now I think I've got the measuring setup correctly... there was a problem with the phono-cable between the SPL meter and the sound card.

Anyway, I did two sweeps, one directly below the driver and one at the port. I've never done measured like this before, so I don't know how to superimpose the two graphs but here goes:

Driver:
http://www.htfhome.com/2007/e4/measurements/tc2000_ss_driver.jpg

Port:
http://www.htfhome.com/2007/e4/measurements/tc2000_ss_port.jpg

Is this good or bad?

I don't know anything anymore... the only thing I know is that my normal measurements (with the SPL meter a few meters away from the sub) looked really awful (but the dips and peaks varied from position to position, so I'm not ready to blame the sub just yet).

I am not an expert on port/driver graphs, but those look about right.

....I don't know how to superimpose the two graphs.....

You can use the averaging feature in REW to "add" the two graphs together.

You can use the averaging feature in REW to "add" the two graphs together.

I didn't know that. Thanks! I'll check it out.

I am not an expert on port/driver graphs, but those look about right.

Do you say so? I was a little worried about the 10dB fall from 50 to 20 Hz...

I just meant that generally speaking, they look ok. One can't trust these RS SPL meters too much anyhow.

Ok, now those look correct. The close mic response of the driver should be dropping off below ~50hz because it is essentially as if it were a sealed sub until the tuning region. It would have been nice if you placed the cursor at the dip to find out exactly where the real world tuning came out to be, but I'd guess ~14hz. So the sub is working properly.

Now that you have RoomEQ figured out, can you attach a sweep from at the seat?

Ok, now those look correct. The close mic response of the driver should be dropping off below ~50hz because it is essentially as if it were a sealed sub until the tuning region. It would have been nice if you placed the cursor at the dip to find out exactly where the real world tuning came out to be, but I'd guess ~14hz. So the sub is working properly.

Phew! Thanks Steve, my heart is beating a little slower now (like 170 bpm or so...).

I'm not sure which cursor you're referring to, or which dip for that matter :confused:

Could you please enlighten a confused soul?


Now that you have RoomEQ figured out, can you attach a sweep from at the seat?

Hehe - the subs are still in the "raw" basement room with concrete walls (as I don't have a HT yet), but I guess I could place the SPL meter in a "virtual seat".

Well, as a matter of fact I did do that last night and the curves look absolutely horrible... But I can provide you with a curve if you want to have a good scare :eek:

Check this out.
http://i101.photobucket.com/albums/m69/soho54/tc2000_ss_driver.jpg

Check this out.

Ok, thanks! I'll do that when I get home :)

Check this out.
Oh man that's great :D It reminds me of poka-yoking at work, got a good chuckle.

:D
Too much military and HR experience.
K.I.S.S. is now a way of life. :rolleyes: ;)

The first close-mic measurement looked like something from between pink noise (http://en.wikipedia.org/wiki/Pink_noise) (increasing 3dB/oct) and red noise (http://en.wikipedia.org/wiki/Red_noise) (increasing 6dB/oct)..

looks good Rune...thank God! now that gives me some hope that no voodoo is going on in our subs! LOL!

Ok, now those look correct. The close mic response of the driver should be dropping off below ~50hz because it is essentially as if it were a sealed sub until the tuning region. It would have been nice if you placed the cursor at the dip to find out exactly where the real world tuning came out to be, but I'd guess ~14hz. So the sub is working properly.

Now that you have RoomEQ figured out, can you attach a sweep from at the seat?

Here's the requested cursor@dip image:
http://www.htfhome.com/2007/e4/measurements/tc2000_ss_cursor@dip.jpg

looks good Rune...thank God! now that gives me some hope that no voodoo is going on in our subs! LOL!

Yeah, let us hope so! ;)

Have you come any further with your twins?

Can you guys explain what happens around 100 Hz here?

http://www.htfhome.com/2007/e4/measurements/tc2000_ss_cursor@dip.jpg

343 m/s / 100Hz /2 = 171,5cm is the length that will produce a standing wave at 100Hz.

Now, how high were your tubes again?

343 m/s / 100Hz /2 = 171,5cm is the length that will produce a standing wave at 100Hz.

Now, how high were your tubes again?

The sonotubes used are 150cm high. Then you'll have to subtract the inner parts of the end caps:

Top end cap:
2x22mm + 5mm for the groove = 49 mm

Bottom endcap:

1x30mm + 5 mm from the groove = 35 mm

A total of 8.4 cm.

So the inner height of the tubes is about 141.6 cm.

Can you guys explain what happens around 100 Hz here?

http://www.htfhome.com/2007/e4/measurements/tc2000_ss_cursor@dip.jpg
Those twitches are caused by room reflections. It's pretty much impossible to exclude the room even when taking close mic measurements.

Those twitches are caused by room reflections. It's pretty much impossible to exclude the room even when taking close mic measurements.
OK. No big deal then...

Here's the curve I get in REW from averaging the measurement from the port (light blue) and driver (pink):

http://www.htfhome.com/2007/e4/measurements/tc2k_averaging.jpg

I've heard that when doing near field measurements of the port, the measurement should be corrected by adding a number of dB's according tho the following formula:

dB's to be added to the port measurement = 20*log(driver areal/port areal)

If this is the case, the port plot should have been adjusted at least 10dB up (but I don't know how to do that in REW).

So besides the measurements, are the subs in their final resting place and performing well? Are you pleased?

So besides the measurements, are the subs in their final resting place and performing well? Are you pleased?

I'm only finished with one. I only have to pop in the top endcap on the other one, but my back has been killing me lately, so I'm not capable of lifting things that weights much more than a SPL meter....

As for the resting place - my HT is non-existing for the moment, so that would be a no - they're not in their final resting place. As soon as my back is back in shape, we'll du a test of the two at the HTF-place to see what they're good for.

In the meantime I'll just do some more or less scientific measurements and learn to master REW.

Oh sorry, I guess I missed the back thing. Definitely take it easy then. Hope you feel better soon. :)

That last graph with the port/driver graphs averaged, looks ok to me.

Oh sorry, I guess I missed the back thing. Definitely take it easy then. Hope you feel better soon. :)

Haven't mentioned it, so how could you have known? I've been trhough it before, so I know it's going to be ok again (eventually ;) ).

That last graph with the port/driver graphs averaged, looks ok to me.

That's good to know :)

Yeah, when you consider the relative inaccuracies of the measurements (not your fault) and the effects of the room, it looks like a good FR.

Yeah, when you consider the relative inaccuracies of the measurements (not your fault) and the effects of the room, it looks like a good FR.

:)


Now that the snow is finally gone, I'll soon enough take the sub outside. Then we can get some real measurements.

Rune,

You can't get an accurate measurement with the RS meter, IMO. You also can't average the port/driver measurement curves to get an approximation of the overall FR.

At least, one would hope that your port graph isn't accurate, or that it won't have as much influence on the overall response as the avreaged graph shows.

The trouble with such a big sub is that an outdoors measurement is the only way you'll be able to see what's happening, anechoically, and I even doubt that a 2 meter distance will be enough at that.

So far, no one has done an accurate ground plane measurement of the alignment you've built, so it would be very interesting to see one.

Hope you're feeling well soon...then git yer butt outside and measure those things! :D

Bosso

Rune,

You can't get an accurate measurement with the RS meter, IMO. You also can't average the port/driver measurement curves to get an approximation of the overall FR.

Do you say so? Well I'm totally green in this measurement game, so I'm just sucking up all tips/info I can get. I imagined that the total output from a sub was driver+port, but there's obviously not as easy as that.

At least, one would hope that your port graph isn't accurate, or that it won't have as much influence on the overall response as the avreaged graph shows.

Yes, it is maybe a little odd (too little pronounced at the tuning frequency?)...

The trouble with such a big sub is that an outdoors measurement is the only way you'll be able to see what's happening, anechoically, and I even doubt that a 2 meter distance will be enough at that.

So far, no one has done an accurate ground plane measurement of the alignment you've built, so it would be very interesting to see one.

Here I go again... I'm not sure what a "ground plane measurement" is... :o

Hope you're feeling well soon...then git yer butt outside and measure those things! :D

Bosso

My back is feeling better already! ;)

Hey Rune,

Grounplane measurements are taken with the mic at gound level at whatever distance is required, 1M or 2M typically. You can check the AV Talk subwoofer tests for some good picutres of this technique....

http://www.subwoofertests.com/testresults.html

Considering that these measurements were taken in doors, that summed response looks pretty close to what it should. The sub is definitely operating correctly, now you just have to worry about proper placement and perhaps some EQ to get your at the seat response flat when your room is finished and everything is set up.

Considering that these measurements were taken in doors, that summed response looks pretty close to what it should. The sub is definitely operating correctly, now you just have to worry about proper placement and perhaps some EQ to get your at the seat response flat when your room is finished and everything is set up.

I'm really glad to hear that, Steve!

Too bad I've already blown my EP2500 :( The clip light for channel 1 is constantly on and from output 1 there's only distorted garbage.

If it hadn't been for my fan mod I could have gotten it replaced, but of course now the warranty is non-existent... well, well - it's only money! Better the amp thatn my subs, I say ;)

Bummer! I have not heard of many failures, but I guess they do happen.

Hey Rune,

Grounplane measurements are taken with the mic at gound level at whatever distance is required, 1M or 2M typically. You can check the AV Talk subwoofer tests for some good picutres of this technique....

http://www.subwoofertests.com/testresults.html

OK. Thanks for the info :)

Too bad I've already blown my EP2500 The clip light for channel 1 is constantly on and from output 1 there's only distorted garbage.
Well that ain't no good! Sorry about that :(

empty

Hey Rune,

Grounplane measurements are taken with the mic at gound level at whatever distance is required, 1M or 2M typically. You can check the AV Talk subwoofer tests for some good picutres of this technique....

http://www.subwoofertests.com/testresults.html

I forgot to mention it: Why measure at ground level? I usually have my ears a little higher above ground than that...

I forgot to mention it: Why measure at ground level? I usually have my ears a little higher above ground than that...

When the mic is at ground level, you don't get an instant reflection from the ground :) Quite brilliant when you think about it

I forgot to mention it: Why measure at ground level? I usually have my ears a little higher above ground than that...

Rune, here is what I got from AV Talk as an explanation:

"Of course, being a hard surface, there are reflections from the ground itself but because the sub and microphone are placed directly on the ground the difference in path lengths is minimised so the phase effect is small. In fact the microphone 'hears' two versions of the sub, the real one and its virtual image reflected in the ground which is why a ground plane measurement made at 2m is 6dB higher than it would be if you measured at 2m with the sub somehow floating in free space. "

I am not sure if that helps, but I often wondered that myself. :confused:

> the microphone 'hears' two versions of the sub, the real one and its virtual image reflected in the ground

Sorry if I intruded your thread RuneW!

Do you think a conical defector attached would rid of the "reflected" sound? I posted this question before, but no replies... :(

http://www.avsforum.com/avs-vb/showthread.php?p=8003152&&#post8003152

Inspired by many here (many thanks to Steve) I'll start to build a sono here soon, my TC-2000 arrived Thursday (3-15). It will have the added conical deflector on the bottom & top (which raises the height to about 78"! :eek:

> the microphone 'hears' two versions of the sub, the real one and its virtual image reflected in the ground

Sorry if I intruded your thread RuneW!

Do you think a conical defector attached would rid of the "reflected" sound? I posted this question before, but no replies... :(

http://www.avsforum.com/avs-vb/showthread.php?p=8003152&&#post8003152

Inspired by many here (many thanks to Steve) I'll start to build a sono here soon, my TC-2000 arrived Thursday (3-15). It will have the added conical deflector on the bottom & top (which raises the height to about 78"! :eek:

Do you have a drawing of these conical deflectors attached to the sub?

I'm actually working on the drawing right now. To keep things simple & prototype, i'll just do a straight 45 angle...

Duevels actually have the "deflector" turned with Plywood

http://www.cd-konzert.de/details/EBLSchnitt.shtml


This was a previous PM...

I'm still thinking about doing the conical deflector on the base just like the Duevel Jupiter...

http://www.6moons.com/audioreviews/duevel3/jupiter.html


Really wanted to impliment this deflector based on what I learned from building the Austin II horns; credit goes to Ron Clarke, the designer as he states here:

"The deflector is a necessary as it prevents the wave front from being sent back to the mouth as well as providing the final wave expansion which allows a more spherical front to develop.
The SB will allow a lower diffraction wave launch as well as providing frequency support from the roll off of the horn action.

Combing both will give a flatter FR curve with a lower Fc.

ron"
Link:
http://http://www.diyaudio.com/forums/showthread.php?postid=1153777#post1153777

I built the black Austins horns here shown with the rear deflector behind the mouth of the horn

http://www.frugal-horn.com/ronhorns.html

I'm actually working on the drawing right now. To keep things simple & prototype, i'll just do a straight 45 angle...

I started a separate thread about "sonosub bottom cone (http://www.avsforum.com/avs-vb/showthread.php?t=740668)". As you can read from that thread, the avs forum users weren't overly enthusiastic about the idea... (but I still think that a bottom cone feels right ;))

Hmmm. That is interesting. I wish someone had some data to support or denounce the use of a cone. It sounds logical (pun intended) but might not translate into practicallity.

I started a separate thread about "sonosub bottom cone (http://www.avsforum.com/avs-vb/showthread.php?t=740668)". As you can read from that thread, the avs forum users weren't overly enthusiastic about the idea... (but I still think that a bottom cone feels right ;))

Wow, we have the same idea! I think it would have benefits. Imagine if you were to shine a flashlight directly perpendicular to a mirror - the light would just reflect right back (distortion). If the mirror was folded, the light would dispurse away.

You're right. Forum users are not enthusiastic about it, so let's start a STORM! :eek: I will impliment the bottom cone (maybe on top as well) on my sonosub :p DARE to be different!

BTW, how are your sonos, any new pictures?

Want to see something funny?

A few people were skeptical about my my DIY-port-grille (which was attached to the sub with magnets) - you were right ;)

I was doing some serious break in with 20-64Hz pink noise when this happened:

http://htfhome.com/2007/e4/video/Erna@20-64Hz_PN.jpg (http://htfhome.com/2007/e4/video/Erna@20-64Hz_PN.avi)
(klikk på bildet for video)

Too bad I didn't get the fun part, because for a while the grille was suspended 4-6 cm over the port like an UFO. I guess I was playing even louder then...

Guess I'll have to look for some other kind of grille. I'm thinking about replacing the fabric with some kind of black (painted) mosquito net thingie, and screw the damned thing in place instead of using magnets...

Want to see something funny?

A few people were skeptical about my my DIY-port-grille (which was attached to the sub with magnets) - you were right ;)

I was doing some serious break in with 20-64Hz pink noise when this happened:

http://htfhome.com/2007/e4/video/Erna@20-64Hz_PN.jpg (http://htfhome.com/2007/e4/video/Erna@20-64Hz_PN.avi)
(klikk på bildet for video)

Too bad I didn't get the fun part, because for a while the grille was suspended 4-6 cm over the port like an UFO. I guess I was playing even louder then...

Guess I'll have to look for some other kind of grille. I'm thinking about replacing the fabric with some kind of black (painted) mosquito net thingie, and screw the damned thing in place instead of using magnets...

Cool picture Rune! At least you know you are movin' some air! :cool:

After quite some weeks of back problems and general inactivity, I finally managed to finish the twins!

Here's the baseplate mirrors that I've waited for for so long:
http://htfhome.com/2007/e4/e4_341.jpg
(Ø40cm)

Here in place in the recession:
http://htfhome.com/2007/e4/e4_342.jpg

The Sonosub in the usual "cannon-position", while the base plate is screwed on:
http://htfhome.com/2007/e4/e4_343.jpg
(The "cannon-position" is when the sub is gently laid across a whold package of Rockwool with one end higher than the other, so that I can work on it. It's the only way to handle the beast singlehandedly...)

Here with both mirrors in place:
http://htfhome.com/2007/e4/e4_344.jpg
(try to imagine them without the dust & dirt from the basement environment ;) )

Unfortunately there is a gap of about 2-3mm between the mirror and the recession wall. It's quite visible with a strong back light like below, but in normal light conditions (like in the cannon picture above) it looks alright:
http://htfhome.com/2007/e4/e4_345.jpg
(maybe I'll fill the gap with black silicon later on. We'll see...)



And here (after about 5 months of work - between family life and house refurbishing)

The TC-2000 Sonosubs finally finished:
http://htfhome.com/2007/e4/e4_346.jpg


I want to thank all of you that have bothered to follow this thread. Thank you so much for your insight, help and moral support!

-Rune Winsevik,
NORWAY

OUTSTANDING Rune.....they look awesome and you should be proud! http://forums.offtopic.com/images/smilies/bigok.gif

great craftsmanship, excellent attention to detail, and a very good implementation overall. You did a good job, and I enjoyed following this thread in parallel with my own! :D

did you ever correct the measurements and that nasty dip and rolloff? lets see the measurements of these bad boys next, ok?

welcome to the club http://forums.offtopic.com/images/smilies/highfive.gif

OUTSTANDING Rune.....they look awesome and you should be proud! http://forums.offtopic.com/images/smilies/bigok.gif

great craftsmanship, excellent attention to detail, and a very good implementation overall. You did a good job, and I enjoyed following this thread in parallel with my own! :D

Thanks! And the same goes to you! :)

did you ever correct the measurements and that nasty dip and rolloff? lets see the measurements of these bad boys next, ok?

welcome to the club http://forums.offtopic.com/images/smilies/highfive.gif

That dip was certainly the room. It only snowed a little today ( :( ), so I'll soon be able to take the twins outdoors. Then I can do some proper measurements.

GOOD JOB Rune!!!!!

Those are some fine examples of sonosubs. Great work!

Congratulations Rune! Your thread has been a wonderful read. When is your HT room ready?

GOOD JOB Rune!!!!!

Those are some fine examples of sonosubs. Great work!
Thanks :)

Congratulations Rune! Your thread has been a wonderful read. When is your HT room ready?
Oh boy... If I use 5 months building a pair of subs, how long do you think I'll spend on a complete HT? :D

Jokes aside - I've got only ONE bathroom to refurbish before the HT project is greenlighted by the authorities (or should I say "authority"...).

We're probably talking of starting this summer. I hope to be ready (sort of) before this winter. Maybe I'll start another build thread for that project...

Most excellent subs, of course! Hopefully you can enjoy them now. :)

(The "cannon-position" is when the sub is gently laid across a whold package of Rockwool with one end higher than the other, so that I can work on it. It's the only way to handle the beast singlehandedly...)
Don't forget the "sonosub turnover", where you flip the sub upside down and let it rest on the top cap, then climb a chair and do what you need to do to the bottom ;)

Fantastic rune, i know this was relief, looks awesome. I am sure you will be the king at that annual event yall have :D .

Good looking tubes, Rune. And very well finished work. :D

Now that the sonos are finished, I need to ask you a completely off-topic question: What's with the Norwegians eating dip sauces and mayonnaise with their pizza? I was visiting northern Norway, i.e. Tromso, Harstad, Lofoten, in November and at Peppe's Pizza, every local ordered dip/mayo/etc with their pizzas... :)

Fantastic rune, i know this was relief, looks awesome. I am sure you will be the king at that annual event yall have :D .
Yeah, maybe ;-)

Don't forget the "sonosub turnover", where you flip the sub upside down and let it rest on the top cap, then climb a chair and do what you need to do to the bottom ;)
Yes, I've been doing that one as well ;)

Good looking tubes, Rune. And very well finished work. :D

Now that the sonos are finished, I need to ask you a completely off-topic question: What's with the Norwegians eating dip sauces and mayonnaise with their pizza? I was visiting northern Norway, i.e. Tromso, Harstad, Lofoten, in November and at Peppe's Pizza, every local ordered dip/mayo/etc with their pizzas... :)

Hehe - mayonnaise? Are you sure about that? Must be something they do up north then... Where I live we sometimes (ok, quite often) use a whitish garlic sauce with the pizza.

But that's only details. Don't you rather want to know why so many Norwegians eat "smalahovud" (sheeps head)? I surely want to know... I guess every country has at least one speciality that only exist because some stupid people have to prove htemselves... :rolleyes:

Congratulations Rune! Of course they look great, what with that Norwegian craftsmanship, attention to detail and all :D Five months is okay, you built them in style and didn't rush the job even with all the pressure from the guys with a need for speed. :rolleyes:

Hope you get to enjoy them for sound now. When is the big hifi weekend with the boys? Didn't you say it was in April? Of course this thread will have to stay alive for a full report and pics from the big event. Keep us informed.

Sincerely,
Craig :cool:

Congratulations Rune! Of course they look great, what with that Norwegian craftsmanship, attention to detail and all :D Five months is okay, you built them in style and didn't rush the job even with all the pressure from the guys with a need for speed. :rolleyes:

Hope you get to enjoy them for sound now. When is the big hifi weekend with the boys? Didn't you say it was in April? Of course this thread will have to stay alive for a full report and pics from the big event. Keep us informed.

Sincerely,
Craig :cool:

Thanks, Craig!

The big day is april 28th, but the plan is to do a "dry run" with only the subs and a pair of PA speakers this sunday. We're also going to do some outdoor measurements of the subs (well, probably one of them anyway). I don't have very advanced measurement equipment, and I'm not entirely comfortable with REW yet, but the big plan is to do a few ground plane measurements of the sub, both standing and lying. Maybe also som near field measurements of the port and driver (also with the sub lying down).

If the results aren't totally hopeless, you'll probably find them here sometime over the weekend :)

I finally got to measure my subs outdoors. Too bad I was haunted by some kind of feedback issue with the SPL meter - REW setup. I'm pretty sure I didn't have this problem when I did my initial measurements at home, but I first noticed this feedback tendencies at a friends house when doing some REW'ing there. I'm not sure if there's some kind of "monitor" feature that has suddenly being turned on on the soundcard, or if it's broken or something... Anyway, we had to do some of the testing at fairly low volumes. This is, of course, not very good combined with the inevitable outdoor background noise. Our greatest problem was birds... :rolleyes:

I'm not sure how much this feedback thing affects the measurements itself. They could be utterly worthless for all I know.... I just have to do it again with properly setup equipment I guess, but meanwhile I can entertain you with the following.

Just remember to take these measurements for what they are: Amateurish crap.
(A few truckloads of salt is also recommended)

---

Here's some pictures of the session.

The sub in the standing position:
http://htfhome.com/2007/e4/e4_347.jpg

The sub in the lying position:
http://htfhome.com/2007/e4/e4_348.jpg
(as you all can see, the SPL meter is a few centimeters from the ground level. I'm not sure how much this influences the measurements...)

During the indoor testing, we noticed a noise during large driver movements. We were fearing the worst, but the sub sounded pure again when it was turned upside down. I hope to God it's only something loose in there. Here's HiFi-plumber trying to see it, but he didn't... I'll have to take it apart to check it:
http://htfhome.com/2007/e4/e4_349.jpg

Well, that noise effectively ended out indoor measurements, so I'll just show the outdoor measurements:

Near-field driver:
http://htfhome.com/2007/e4/measurements/near-field_driver_lying.jpg

"Ground-level" 2 meters from the sub [standing]:
http://htfhome.com/2007/e4/measurements/2m_groundlevel_standing.jpg

"Ground-level" 2 meters from the sub [lying]:
http://htfhome.com/2007/e4/measurements/2m_groundlevel_lying_soundking.jpg
(Soundking PA amp)

"Ground-level" 2 meters from the sub [lying]:
http://htfhome.com/2007/e4/measurements/2m_groundlevel_lying_ramsa.jpg
(Ramsa PA amp)


I'm not sure how to interpret these measurements. I'm going to EQ the subs, so I'm not too worried about peaks. Seems like I've got one fairly broad peak centered around 30Hz or so. Then again, this peak is almost non-existent when I switched to the (lower powered, but higher quality) Ramsa amp. This last measurement is at quite low levels. I don't remember why here and now, but it may have been the (/&¤&%¤/% feeedback issue again.

I'll leave it up to you guys to interpret these measures...

---

As for the indoor measurements.... well, I guess the subs delivered less than expected. Lots of driver movement and less noise is a very short description of what happened. That said, the room is quite big. We're talking close to 20.000 cubic feet here with an opening to an adjacent room of about 8000 cubic feet. It's a difficult room, but I was hoping for a little more that I got...

Well... they should be able to fill my HT at least...

You know what, you're probably right about the monitor feature producing the feedback. When I went to test my TC-2K up to 500Hz, I decided to hook my computer directly up to the Buttkicker amp. Well for my first attempt, I had the same issues you had with bad feedback (which as you say, is not bad at low levels).

I gave up out of frustration..but sure enough, when I tried it a second time I remembered that there was monitor option in the soundcard control panel. That obviously fixed the problem...

Ilkka and some other folks more experienced with such measurements could offer a lot of advice, but I think it would indeed be much better to take measurements at higher spl (at least using the RS meter)...like, 85ish. That peak you see in one of the measurements must be due to the amp, because in any type of GP measurement, it most certainly shouldn't exist.

And 20,000 cubic feet! Whoa....yeah, these subs are not one I would build for a massive room like that (I know it isn't the room they'll be in for good...). In a room like that, horns wouldn't be a bad idea, but at the very least, even the TC-2Ks tuned to 19 or 20Hz with more power would be more ideal.

You know what, you're probably right about the monitor feature producing the feedback. When I went to test my TC-2K up to 500Hz, I decided to hook my computer directly up to the Buttkicker amp. Well for my first attempt, I had the same issues you had with bad feedback (which as you say, is not bad at low levels).

I gave up out of frustration..but sure enough, when I tried it a second time I remembered that there was monitor option in the soundcard control panel. That obviously fixed the problem...

Ilkka and some other folks more experienced with such measurements could offer a lot of advice, but I think it would indeed be much better to take measurements at higher spl (at least using the RS meter)...like, 85ish. That peak you see in one of the measurements must be due to the amp, because in any type of GP measurement, it most certainly shouldn't exist.

And 20,000 cubic feet! Whoa....yeah, these subs are not one I would build for a massive room like that (I know it isn't the room they'll be in for good...). In a room like that, horns wouldn't be a bad idea, but at the very least, even the TC-2Ks tuned to 19 or 20Hz with more power would be more ideal.

Yeah, I guess we don't get much help from this room... :(

I think, I'll use Erna 1&2 in addition to Erna 4&5 (the tubes), so they don't have to do all that work alone...

As for the soundcard, the problem is that I cannot find any control panel installed (and I don't have the original driver CD that came with the card)...

Wonder how Rune's big day went :(

Craigo