Very High Quality DIY speakers anywhere? - Page 77

Thanks Jeff! The design was functional. I wanted them near the ceiling due to a wall not shown which has a large opening in it instead of a door. So, I did up the room in UGNX (a CAD program) and built a model. I worked out an equation using the area of a trapeziod to allow me to vary the angle of the face while keeping the area of the trapezoid constant using the depth of the cabinets as a variable. I made a ray off the tweeter and modified the angle until it was aimed a little above the head of the sweet spot. This arrived at a 35 degree angle and gave me the final depth dimensions.
As far as the hanging method, I have seen picture frame hangers that work similarly. You have a piece of metal with an angle face that you hang on the wall forming a kind of pocket, and a triangle of metal that you affix to the picture. Then you just drop the pictures angled surface into the wall mounts angled surface and bingo, it's not going anywhere.
Using this method the speakers are very securely mounted. Each one has 3 screws in it, either through to a stud or using something like a drywall toggle, which is claimed to support 90 lbs each. The speakers only weigh 15 lbs.

Last night the only 7.1 capable DVD I could find was Gladiator with DTS ES. It sounded great and listening to other dvds, the 5.1 sounded great too. I was a little worried about the high mounting position (10 foot ceilings), but so far I am really happy.

Kevin

After a year with my MB20s, and enjoying the heck out of 'em, I decided to waste some time and make proper cabinets. Mostly I just wanted an excuse to play with some new tools. I decided to try veneering, and since I didn't want to paint the veneer I went with a few coats of poly. I also decided that if my wife liked them well enough I could put them upstairs in the living room and start a new set, maybe Audax , for the theater.

Here's the finished product. Shiny but nice looking, IMHO.


BTW, kroberts I really like your mounting plate. It looks good and sounds very functional. I'll have to go back and read more of your posts to find out what it is you built. The finish looks good. I'd look at painting your ceiling though. A white ceiling would be more distracting to me, I know I still have one. Someone in the HT Building forum was talking about certain shades of blue, for ceiling treatments, that look very grey, and non-reflective, in dim light. I'm thinking of doing this myself.

Dougie085, Just to let you know, I built these for about $250 per pair. So a full set for 5.1 has cost me about $800 (five MB20s plus a sub).

Gyvven,
Those speakers look great. The veneer looks great and I like black around the baffle.
I don't have much else to chronicle the rears, but there are posts for my center back there. If you would like more details on the mounting plate, just let me know and I will post some more.

As far as the ceiling, it isn't a problem for me. My ceilings are 10' and the top of my screen is 3' below that. The wall behind my screen is the grey you see in the picture, I don't even see the ceiling when I am looking at the screen and there is very little spillover onto the ceiling. I have never looked at a pj with the screen close to the ceiling, but I can understand how that would be distracting.

Kevin

I finally have the 7 of the 7.1 done! It has been 2 1/2 months, but they are done! I got the fronts done yesterday, and they are awesome. I tested some of my music DVDs last night, and I am very happy with the results. Here is the overall view of the front


Here is just the front speaker and stand


And here is a closeup of the front


The finish is Minwax Sedona Red on Flexwood Cherry veneer with 6 coats of gloss followed by 2 coats of satin. The black is Krylon Ultra Flat Black over Kilz spray primer.

Here is a closeup of the rears


Here is an overall view of the 4 rears on the wall


Thanks to everyone for the help and discussion!

Kevin,
Great job! Your front stands look like the ones I built. A lot of people only like floor standers but I think these Audax MTMs on stands look really good. When someone touches the cabinets, they know immediately, they aren't cheap.

Jeff,
I like the look with the stands also. Your stands, JL,s and a link JL posted way earlier in the thread were my inspirations. With the stands you get a change in width which adds some interest as opposed to the monolith look of a floorstander.

Kevin

Kevin,

Your speakers came out looking great. Nobody will believe you built them yourself. Wait till they break in a bit more, the sound gets even better.

I love the ceiling mounted side and rear enclosure design you came up with... very nice.

Thanks for the compliment about my stands serving as part of the inspiration for your front channel stands. I looked at a lot of stands before building mine and my wife assisted me in eliminating most of them as possibilities . I wanted mine to disappear when the lights were dimmed, so I was forced to use flat-black to minimize reflections. You have a bit more brightness from your projector, so you can get away with a bit more light in the room than I and use a real wood finish.

Did you brush on or spray the finish? 8 coats of finish is quite a bit. They look really nice in the wood/stain you used. I hope you got a chance to listen to them before the final coat of finish was dry.

Now, Enjoy, sit back and watch a movie or two, and then let us know how they are sounding.

Joe L.

Thanks Joe,
I wiped on the poly based on Jim Salks recommendations earlier in the thread. The coats are so thin that you need more to build it up. It took 6 coats of gloss to fill in the grain and get a consistently glossy finish before I put the satin on. It dries in 2-3 hours, and I am in Arizona where there is low humidity, so I got all of the finish on in 2 days, let it sit for one day and assembled on the 4th. I did get some lint/dust in the finish though, and I didn't want to sand too much because I didn't want to remove the stain. You can't see it unless you get really close, so most people will never notice it.
For my next wood finishing project I think I will use Formby's tung oil. I was at a friends over the weekend and he has an armoire he finished with it and it looks great. It was a nice satin finish with no dust in it.

As far as glare I can see a highlight on the roundovers closest to the screen sometimes, but it isn't too bad, and honestly no worse than what I see off the top roundover on the center channel every once in a while, so I don't think it will be annoying.

Kevin

Kevin,
You can see, or... more accurately, it is almost impossible to see the finish on my flat-black Audax HT stands, even with the flash on my camera. My older pictures had had the gamma modified in a photo-editor so you could see some detail.

You can also see my current project, a pair of sealed 18" driver subwoofers built into the stage beneath my screen. Each half of the stage is about 12.5 cubic feet internal volume. My deadline to finish is *before* our Christmas party this weekend when guests will arrive. Wish me luck.

That is a coffee mug sitting between the two drivers to give you an idea of the scale. They are NOT small. My old 15" Adire Tempest sonosub is on the right. The new subs combined will be 5 times (13Liters) more displacement as it (2.5Liters). Hey, how many times can you say with a straight face to a guest in your house "that size really does matter"




Joe L.

Geez, JL, I'm not sure I'm gonna be very happy being able to hear your subs down here in Texas. I'll be sure to put the cops ph # in my speed dial....

JL,
Those beasts are going to be amazing! I can't wait to build a sonosub. I would love to hear those when they are done, but I am also glad I won't, then I will be happy with a sonosub.

Kevin

Joe, that is going to be one HUGE stage! When I did that little model in Pro-E showing what I envisioned your project to look like, I didn't expect that! Probably part of the issue is that those drivers are not only big in diameter, but also taller than I had thought they would be, which makes it harder to design around.

Good luck on the completion. Since it has been so long since we have heard about progress of them, I REALLY wish you good luck, since it doesn't seem like you have been doing much with them! Maybe it just takes a fire to get lit under your butt?!

Scott,
Lots of things kept me from working on the subwoofer/stage... but now, I have a deadline and hopefully, all the parts, pieces and enough glue to keep me busy.

I too did not expect the basket to be shaped as it is. It does not allow me to angle the driver as I wanted and still get everything to fit. If we did, you would have quickly seen in your 3D rendering that it simply would not fit. So, back to the drawing board and I ended up with a more standard down-firing arrangement. I do have tons of internal cross-bracing as seen below.

I did a few prototype arrangements once the curved front was assembled initially thinking I could do a upward firing arrangement with a top plate to protect the drivers, bit my wife and I agreed that the down-firing arrangement looked better. The top will be covered with black velvet to eliminate reflections from the screen.

Yes, sometimes it takes a bit of an incentive to get things going. (pending guests) The problem is that the existing sonosub is pretty decent, in fact, more than decent... and we watch a lot of movies, and you can't make sawdust when you are watching movies. And we went on vacation, and my wife and I took evening ballroom dance classes at the local community college (will I ever find an occasion to Tango? Hey... I know how!!) and it's not like I don't have a subwoofer already... Now that things are back to normal... Must... get... more...power...tools...


Note: advice to fellow DIY'ers, if you use one of the new polyurethane glues (Gorilla Glue is one brand) wear gloves. Oh yes, don't let a drop of glue accidentally fall on your wrist just above your wristwatch. If you do, and it wicks itself under the watch, the watch will be glued to your wrist in short order. Now, it will come loose, but not without sacrificing all the hair on your arm that used to be under the wristwatch. Now, don't ask me how I came to have this knowledge, but let's say it is "first hand" knowledge. (Ouch...)

Joe L.

Final set of braces in the center section still needed to be added when this picture was taken.

I LOVE the stage idea.....ive been thinking about how i want to have under my screen setup and this would actually be nice because it would give me a place to put my electronics and take care of the sub so that its not off in a corner somwhere taking up space lol and i could probably build in a little shelf to house my reciever dvd player HTPC and everything.......excelent idea....this is in my living room right now lol so i dont really want to have an electronics rack somwhere..i really think it would look nice incorperrated into a stage type setup like that....for the 18" drivers what is the total depth width and height of the cabinets when they are put together? the 18's may be to big for me....i might have to do 15's or maybe a single 18" also what are you powering these things with? 2 plate amps? i would think somthing more powerful maybe a pro amp or somthing

Dougie,
My stage is 8 feet wide, about 36 inches deep in the center tapering to 30 at the ends, and about 18 inches high. As Scott said, it is HUGE.

I have a NADY XA-1100 pro amplifier to power the new sub. It is a lot more powerful than most plate-amps. It has two channels, rated 475 watts per channel into 4 ohms. I'll use one channel for each sub driver. It will be loafing with 4 ohm loads since it is rated for use with 2 ohm loads. You can see it here: http://www.nady.com/products/product...aampls_pg.html I am aware that there are some high-power plate amps, but the Nady was way less expensive. Under $150, shipping included, from amazon.com when I ordered it a few weeks ago.

Joe L.

i was thinking maybe i could do a simaler setup with 4 10" subs id like it to be 2 seperate cabinets because i live on the third floor of this building and when i move id like to take it with me and that would make it easier lol of course it would be probably 3 feet shorter then yours lol 8 feet pretty much takes up a wall my current projector screen is only about 75" diagnal and im thinking about getting the Optoma DV10 which would be hard to get the screen under 100" but i might just wait and get a 4805 or even one of the 720p projectors but i just want to make it a little wider then my screen maybe i'll make a couple design scetches of what im thinking in my head and post them here

Doug, glad you found this thread as well! FYI everyone, Doug is looking at using a JL Audio 12W7-3 monster that a friend is going to almost hand to him. For those who don't know anything about this driver, here are the specs:
Fs: 27.2hz
Qes: 0.514
Qms: 7.807
Qts: 0.482
Vas: 2.33 cu ft/66.0 L
Xmax: 1.15in/29mm (one way)
Sd: 84 sq in/0.0542 sq m.
Re: 2.47 ohm
Znom: 3 ohm
Pt: 750w
driver displacement: 0.14 cu ft/ 4.0 L
net weight: 45 lbs/ 20.4 kg



He is trying to figure out if this thing would work well for HT. You guys want to give your input?

Oh, Doug, BTW, I don't think you would want to have a subwoofer cabinet that also holds your equipment, unless you put in some serious vibration dampening stuff so that you could stop the vibrations from shaking the crap out of your equipment. I could just imagine that you would have to turn off you subs anytime you wanted to watch a DVD so that it wouldn't skip...

It'll need a lot of power as it's pretty inefficient, but it models pretty nice.

W7s are supposed to sound really nice. I have some 12W6s in my car...

yea i saw a 1000watt plate amp or i was thinking of a pro amp but i dont know if im going to use the w7 i think i might use somthing else instead and if i made the stage it would probably be like 4 10's or somthing and to make vibrations better where the equipment sits i could lay down a 1/4" rubber mat of some sort that should take care of things but then again maybe not....if the top were 2" thick it shouldnt move much anyways and then with the rubber mat on top i really couldnt imagine it moving much....lol

i was also thinking like maybe 6 8w7's but im not sure that would be enuogh output...lol

Doug, I think you underestimate the power of four subs shaking! I would not want my equipment attached to the sub cabinet, but if I was going to do it, I would want the equipment on isolators similar to raquet-ball halves or something better. There are lots of things available on the market, some softer than others that may do a better job.
I would not trust a 1/4" thick rubber mat, a 1/2" thick neoprene mat would probably be better, something soft...

but my point is if the cabinet is sturdy enough and the top is thick enough it shouldnt vibrate much but as i said im not sure...the biggest sub ive had was a single 12" store bought and my current sub is a Klipsch dual 8" sub

Depends on the way the drivers are mounted as well...

yea....i dont know...i just think i could build it to look verry clean and it would be nice to not have an extra box sitting in a corner lol seems like a good idea most of my movies are on a HTPC anyways lol so they are played off the hard drive...but i dont know about vibrations my dual 8" klipsch sub has some nice output but it doesnt vibrate that much

i have a while to think about the sub design anyways i still have to build my speakers lol which im going to build a set of GR-Research av series the A/V 3 and A/V3S and the A/V 1RS's so that will be fun lol and then i'll start planning for the sub. right now im mapping out my options and picking the right one because the sub i build will probably be the one i stay with for a while eventually i want to design my own speakers but the sub will most likely go unchanged

Nearly there...

I have the left side proscenium-sub assembled to where I could give it a try, HBO was playing "Flight of the Phoenix" so I listened to its soundtrack while I kept working on the other half of the stage.

Wow... and I thought my old 260L Adire Tempest sub could do justice to the soundtrack... nope... no going back now.

With only one 18" Ascendant Avalanche driver, and still using the old 250 watt plate amp, this thing worked wonderfully. The soundtrack of the plane crash was intense. The whole room seemed to pulse with the vibration. I can't wait till tomorrow when I get the other Avalanche driver mounted in the right hand half of my proscenium/sub-enclosure and the new amplifier in place to power both drivers. Then I'll have to see if I have some time to try to equalize them before my guests arrrive on Saturday. I still need to cover the top with a dark fabric. Might not get to the equalization...

Joe L.

Driver installed in left hand side of stage/proscenium. Next step was to fill with batts of fiberglass insulation and attach the top.

Hey Joe, that thing looks like a beast! As usual, your construction also looks great. What do you plan to use for equalization? I still have another section of sonotube and I keep saying I'm going to build a second one. I bought a BFD just for that purpose. It's mounted in the rack and waiting for that 2nd sub.

Joe,

Does your stage sit directly on the floor, if so, how do you have any clearance for the movement of the sub? I see the feet in your first picture, but this last one looks like it sit's directly on the floor? I'm sure you have it figured out, but it's just hard to tell how you're doing it from the pictures.

Jeff,
I have a BFD equalizer. It should simply be a matter of plotting the new response curves once everything is in place.

I gave my other half of my original piece of Sonotube to an AVS member (BrianMat) who lives about 20 miles west of me.
He was very happy with this sub he built with it

Joe L.