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First build - Octo SI 18's with flat packs. - Page 3

post #61 of 790
Dang Carp! Looking good my man! cool.gif
post #62 of 790
Thread Starter 
Quote:
Originally Posted by michaelscott73 View Post

Anyone watch Breaking Bad? I just got a vision of Carp firing up the subs and every piece of metal in his house flying to the floor of the room above his basement.

Ha, I haven't seen that show but this made me laugh anyway. biggrin.gif
post #63 of 790
Thread Starter 
Quote:
Originally Posted by Gorilla83 View Post

Carp - Get them hooked up and do some experimenting. If you find that you want more output, they will for sure take a bit more power than a single CV5000 spread across the 8 subs. smile.gif You can add more subs and/or power to satisfy your power craving. I think you will like what you hear though. biggrin.gif Does anyone around you have a second CV5000, Crown, or a Clone amp you could borrow to simulate an unlimited power scenario?

Also - If you've got a concrete floor like me I can tell you that the nearfield subs make a HUGE difference in tactile response.

Yeah, I've figured that out using the MBM-12. Hmmm... I suppose I could put a couple of SI subs behind my loveseat, I'll try that out too. I'm starting to understand why Austin has 16 subs!! eek.gifbiggrin.gif Let's see, I could go 4 stacked in each front corner, 4 under the screen, 2 under the right side surround speaker 2 under the left surround speaker, 2 behind the love seat, maybe 1 or 2 in the back corner by the computer. Ok, that means I need.... 16-18 subs!!

Obviously kidding, I won't buy anymore until I experiment a LOT and I'm sure I'll be fine with 8.
post #64 of 790
Thread Starter 
Quote:
Originally Posted by edoggrc51 View Post

Dang Carp! Looking good my man! cool.gif

Thanks edogg - I have to say I'm starting to enjoy the DIY thing. With the help of a friend I built 2 more boxes last night and we plan on doing 2 or 3 more tonight.
post #65 of 790
Quote:
Originally Posted by carp View Post

Yeah, I've figured that out using the MBM-12. Hmmm... I suppose I could put a couple of SI subs behind my loveseat, I'll try that out too. I'm starting to understand why Austin has 16 subs!! eek.gifbiggrin.gif Let's see, I could go 4 stacked in each front corner, 4 under the screen, 2 under the right side surround speaker 2 under the left surround speaker, 2 behind the love seat, maybe 1 or 2 in the back corner by the computer. Ok, that means I need.... 16-18 subs!!

Obviously kidding, I won't buy anymore until I experiment a LOT and I'm sure I'll be fine with 8.

I hear ya, man. I've already got twelve 18's set up for the front with the twelve 15's from the mega mains plus a possible double or quad 18's behind the couch. And my room is smaller than yours! eek.gif
post #66 of 790
Quote:
Originally Posted by carp View Post

This may sound nuts, but I'm a bit concerned that if I spread them out too much I'll lose too much of the ridiculous head room that I am after.

Yep, that sounds nuts. smile.gif

Merely a couple of those subs would very likely be enough for virtually all material, except the deepest content.
Down in the deepest content, the wavelengths at 20hz are 56.5 feet long! That said, the subs become essentially co-located as the frequency lowers.
By manipulating the two groups acoustic summation, you have a tool for furthering your efforts toward a smooth response through the room's modal region. This manipulation, in no way compromises the systems overall capability in the deep bass range. Any small manipulation you make for smoothing, will not alter the deep bass wave's phase relationship to one another in any significant manner... to a point where it would affect it or be subtractive in a way that would detract from the deep bass ability.

Throw in PVG (what's your room's dimensions?), and the cool manner in which PVG interacts in support of significantly lessening distortion, and son, you'll be fine.

Worrying about headroom .... rolleyes.gif


j/k,

I understand the trepidation, but spreading the subs around doesn't detract from SPL capability down where you need it the most, in any way. It merely alters the way the drivers excite which modes, to which extent ... selective mode cancellation.
post #67 of 790
Quote:
Originally Posted by Scott Simonian View Post

I hear ya, man. I've already got twelve 18's set up for the front with the twelve 15's from the mega mains plus a possible double or quad 18's behind the couch. And my room is smaller than yours! eek.gif

Some of you guys need help...............................seriously.











biggrin.gif
post #68 of 790
Carp,

On a side note can you post a close up of those Metallica albums you have hanging on the wall? Thanks.

James
post #69 of 790
Quote:
Originally Posted by carp View Post

Yeah, I've figured that out using the MBM-12. Hmmm... I suppose I could put a couple of SI subs behind my loveseat, I'll try that out too. I'm starting to understand why Austin has 16 subs!! eek.gifbiggrin.gif Let's see, I could go 4 stacked in each front corner, 4 under the screen, 2 under the right side surround speaker 2 under the left surround speaker, 2 behind the love seat, maybe 1 or 2 in the back corner by the computer. Ok, that means I need.... 16-18 subs!!

Obviously kidding, I won't buy anymore until I experiment a LOT and I'm sure I'll be fine with 8.

I just didn't want to take any chances... I would have been livid if I picked up 8 and still had "the itch." I took the avenue I figured would ensure the thought of "do I need more" would never pop into my head. Heck, I'm hoping the first 8 I get up and running will satisfy the itch and the other 8 will just help future proof me...
Quote:
Originally Posted by Scott Simonian View Post

I hear ya, man. I've already got twelve 18's set up for the front with the twelve 15's from the mega mains plus a possible double or quad 18's behind the couch. And my room is smaller than yours! eek.gif

Your going to add 4 more 18's Scott!?!

Bet you are kicking yourself for getting those D4's now...lol...
post #70 of 790
Quote:
Originally Posted by michaelscott73 View Post

Anyone watch Breaking Bad? I just got a vision of Carp firing up the subs and every piece of metal in his house flying to the floor of the room above his basement.

Quote:
Originally Posted by carp View Post

Ha, I haven't seen that show but this made me laugh anyway. biggrin.gif


Oh man, the recommendation, start at the beginning, thank us later, serious, it's tremendously well executed.

The only caveat, it's not for children .... but it is so, so good. It really is.

The production quality with this level of television based action/drama stuff is phenomenal. Breaking Bad is at the top of the heap ...

There's others we really like too, Homeland, Sons of Anarchy .. but this is a sub thread. cool.gif
post #71 of 790
Quote:
Originally Posted by popalock View Post

Bet you are kicking yourself for getting those D4's now...lol...

Lol! Of course not! I plan on getting one or two more pairs of d4's. I love when I can get d4's. They're better. They're just... better. smile.gif

Plus... they still have some in stock right now. I don't have to wait til June or whenever. biggrin.gif
post #72 of 790
Carp, this is spectacular overkill! biggrin.gif

As to a few comments made, I completely agree with FOH about the colocation not being an issue for summing the output of all 8 drivers. You should be capable of well above reference at every frequency, only limited by your signal chain's roll off.

I would also think that each box is going to be roughly about 75% the output of a SubM HP (total guesstimate based on displacement), assuming proper amplification. Plus, the SubM has a 7hz HPF, which you won't have. As FOH said, 2 of these boxes would likely get you reference for all but the absolute lowest frequencies, and 8 will be significantly over.

Personally, if at all possible, I think 4 would be perfect when placed on 3 walls like PeteW did. Obviously, each room is different, but that centered-on-3-walls approach showed spectacular results. Check out the three posts following that link and see what the final response was without any EQ. Still wanting to get his miniDSP back in the chain to apply an LT for 3-10hz...someday.

Edit: looking further at your pics, it appears that one on either side of the center channel, and one directly underneath your SL & SR channels would fit, maybe working towards the slightly-modified Geddes approach (I think that's it) mentioned above, and give you the nearfield tactile response so many here talk about.
Edited by nube - 3/5/13 at 10:55am
post #73 of 790
Thread Starter 
Quote:
Originally Posted by FOH View Post

Yep, that sounds nuts. smile.gif

Merely a couple of those subs would very likely be enough for virtually all material, except the deepest content.
Down in the deepest content, the wavelengths at 20hz are 56.5 feet long! That said, the subs become essentially co-located as the frequency lowers.
By manipulating the two groups acoustic summation, you have a tool for furthering your efforts toward a smooth response through the room's modal region. This manipulation, in no way compromises the systems overall capability in the deep bass range. Any small manipulation you make for smoothing, will not alter the deep bass wave's phase relationship to one another in any significant manner... to a point where it would affect it or be subtractive in a way that would detract from the deep bass ability.

Throw in PVG (what's your room's dimensions?), and the cool manner in which PVG interacts in support of significantly lessening distortion, and son, you'll be fine.

Worrying about headroom .... rolleyes.gif


j/k,

I understand the trepidation, but spreading the subs around doesn't detract from SPL capability down where you need it the most, in any way. It merely alters the way the drivers excite which modes, to which extent ... selective mode cancellation.


Wow, very cool. I did not know this! That makes so much sense but I either have never read that or I did and didn't understand - which is quite possible.

My room is 17' 3" wide, 23' deep, 7' 8" tall with half a staircase in the back.

So since a 50hz wave length is 22 feet long, does that mean the subs will act like they are co-located (assuming the distance/delay settings are correct) from 50hz down? I know it probably won't be an exact hz number, just wondering what the ballpark will be.
post #74 of 790
Thread Starter 
Quote:
Originally Posted by exojam View Post

Carp,

On a side note can you post a close up of those Metallica albums you have hanging on the wall? Thanks.

James




I have a much closer shot on my computer at home, I'll post that later.
post #75 of 790
Thread Starter 
Quote:
Originally Posted by FOH View Post


Oh man, the recommendation, start at the beginning, thank us later, serious, it's tremendously well executed.

The only caveat, it's not for children .... but it is so, so good. It really is.

The production quality with this level of television based action/drama stuff is phenomenal. Breaking Bad is at the top of the heap ...

There's others we really like too, Homeland, Sons of Anarchy .. but this is a sub thread. cool.gif



Thanks, that sounds like something I need to catch up on this summer when it's nothing but free time. I have friends that have made similar comments about the show.
post #76 of 790
Thread Starter 
Quote:
Originally Posted by nube View Post

Carp, this is spectacular overkill! biggrin.gif

As to a few comments made, I completely agree with FOH about the colocation not being an issue for summing the output of all 8 drivers. You should be capable of well above reference at every frequency, only limited by your signal chain's roll off.

I would also think that each box is going to be roughly about 75% the output of a SubM HP (total guesstimate based on displacement), assuming proper amplification. Plus, the SubM has a 7hz HPF, which you won't have. As FOH said, 2 of these boxes would likely get you reference for all but the absolute lowest frequencies, and 8 will be significantly over.

Personally, if at all possible, I think 4 would be perfect when placed on 3 walls like PeteW did. Obviously, each room is different, but that centered-on-3-walls approach showed spectacular results. Check out the three posts following that link and see what the final response was without any EQ. Still wanting to get his miniDSP back in the chain to apply an LT for 3-10hz...someday.

Edit: looking further at your pics, it appears that one on either side of the center channel, and one directly underneath your SL & SR channels would fit, maybe working towards the slightly-modified Geddes approach (I think that's it) mentioned above, and give you the nearfield tactile response so many here talk about.

Cool, good idea I'll try this configuration for sure too. Thanks for the link. So, if I have them in the above configuration I still have 4 subs left. Does Geddes say that adding subs in other places other than the 3 will cause a negative effect? I need to do some reading but don't have time right now.

I don't know if a single SI has 75 percent of a Submersive. They are supposed to be almost identical to the Dayton HO 18's and a dual opposed Dayton had more output that a single Submersive when we compared them in my room, but it was close - very close.
post #77 of 790
Maggies !
post #78 of 790
I don't know, carp, about the comparison with the SubM. I was mostly thinking about the total amount of displacement. I thought the SubM drivers were ~23mm xmax, pretty much the same as the SI. Figuring in that 7hz hpf, I would think... Maybe someone more knowledgeable could speak on how two 18s could have almost the same output as two 15s with similar xmax and power levels.

Not knocking the SubM, just curious how you'd accomplish this.
post #79 of 790
To be fair carp, I'm not sure we can make any real comment between the two other than our experience during the XM:FC beach scene. Given that the Daytons were about 4-5 days old at that point and I'm a wuss tongue.gif I don't think there's any way we can say how close to their max we had them. If we'd reduced the LT a bit (or better yet, run 4 ohm stereo) then we could've probably done so, but how much they had left in the tank is anyone's guess.
post #80 of 790
Thread Starter 
Quote:
Originally Posted by MrSmithers View Post

To be fair carp, I'm not sure we can make any real comment between the two other than our experience during the XM:FC beach scene. Given that the Daytons were about 4-5 days old at that point and I'm a wuss tongue.gif I don't think there's any way we can say how close to their max we had them. If we'd reduced the LT a bit (or better yet, run 4 ohm stereo) then we could've probably done so, but how much they had left in the tank is anyone's guess.

Yeah, but remember we ran that scene and others at master volume -5 and the sub anywhere from 10 to 15 hot when we were recording the max output with the omnimic. We kept turning up the volume and runing scenes over and over until the db readings stopped going up and they were almost identical for every scene with a slight edge to the Dayton's.
post #81 of 790
We still had your SMS-1 in the chain at that point, no?
post #82 of 790
Wow. Pretty impressive so far! I searched through the thread pretty quickly and saw a hint of a listening impression...did I miss a larger chunk somewhere or have you done anymore listening to the SI's?
post #83 of 790
Thread Starter 
Quote:
Originally Posted by MrSmithers View Post

We still had your SMS-1 in the chain at that point, no?

No, we did the first part but took it out mid way through which was when we found there was a 6 or so db difference in max spl between having the sms-1 in and not having it in. I have our max numbers saved in excel at home, there was a drastic difference with taking out the sms-1. A couple days later I did more testing to make sure, and got the same result.

Remember, all our back and forth comparisons between the 2 subs, the max numbers were almost equal with all the scenes between the them. It wasn't until the beach scene of the x men movie that the difference in output became more clear, and even then the max spl number was very close between the 2.
post #84 of 790
Thread Starter 
Quote:
Originally Posted by Electrodynamic View Post

Wow. Pretty impressive so far! I searched through the thread pretty quickly and saw a hint of a listening impression...did I miss a larger chunk somewhere or have you done anymore listening to the SI's?

I have. I did a ton of going back and forth between the Submersive and the SI. I do think the Submersive has more extension in the bass between 100-200hz. I tried some songs using a 150hz crossover and the Submersive handled that better. The thing is, I never use a crossover that high anymore so that is irrelevant. If I still had my eD speakers this would have mattered because a lot of music sounded better with this high crossover back when I had dual Submersives.

I've never been a believer in break in, but I have to say at first I was a little worried. When I first started going back and forth I felt like the Submersive had a bit more precision and definition to the notes over the SI. As time went on however, that perception started to change until eventually I felt like the SI sounded every bit as good as the Submersive but with a bit more "weight" to it (which I really like btw), similar to how I described the sound of the Dayton drivers back when I was comparing them to the Submersive. So who knows, could have been break in, my brain/ears breaking in, placebo, etc. but at any rate I love how the SI sounds.

Since I have one sub hooked up to the Cerwin Vega CV 5000 amp I'm not pushing things at all. The only movie scene I watched was the Iron Man 2 scene a number of times at 15 under reference. Going back and forth I couldn't tell the difference between the SI and the Submersive at this level on this scene.

Sometime I would like to do a head to head comparison of the Dayton and the SI.
post #85 of 790
Carp, your A/B comparison was with the first two boxes you built against the submersive or a single against a single? What scene? Curious what your feelings would be at reference.
post #86 of 790
Thread Starter 
Quote:
Originally Posted by michaelscott73 View Post

Carp, your A/B comparison was with the first two boxes you built against the submersive or a single against a single? What scene? Curious what your feelings would be at reference.

Just a single. Currently I have 2 more boxes finished (no sanding or painting yet) and have the bracing done on the remaining 5.

The scene was the opening ACDC Shoot To Thrill scene. I don't want to push it yet, I'm pushing quite a bit more than the recommended 600 watts until I get some more subs hooked up to the amp. I know I could go louder with a single SI driver than -15, but I don't want to take any chances.
post #87 of 790
I too am now a firm believer in "break-in" after building a sealed Dayton 18" HO. At first the bass was deep and powerfull, but seemed to be stiff and a bit inaccurate. But after a few weeks of listening it's really tightened up in terms of precision and speed. It's almost as if it's two different subs.

I'd be interested in a SI to Dayton showdown as I've started hearing people say that they've found the Dayton to be more accurate. But I don't know if anyone has written anything about a comparison yet.
post #88 of 790
Thread Starter 
My thinking right now is unless you need to use a higher crossover than 100hz you can't do any better than the SI's. Now, I haven't heard a lot of subs out there, but here are some of the nicer subs I have ever heard:

Submersive duals **
Cap Ported duals **
Cap Sealed duals
Cap 2 Sealed duals
Orbit Shifter duals *
SVS Ultra duals
HSU VTF-15 duals *
Epik Empire
Dayton HO 18" dual opposed*
Stereo Integrity 18" **

* means I have heard them in my room, ** means I owned or own them. With the Orbit Shifter and VTF 15 I heard them on separate occasions, in my own room I just heard singles.
post #89 of 790
Carp - PLEASE get 4 of them done soon, I'm dying to read what you think once you get them up and powered properly. smile.gif Oh, and once you do make sure Jonathan is around. biggrin.gif
post #90 of 790
Gorilla83,

I only got two things to say...

1) Have you unscrewed your bathroom light bulb with your silverbacks?
2) Have you knocked down a bass trap when it 'trapped more than it could handle'???


Cause I personally witnessed your JTR Caps do both in your room the last time I was there. cool.gif

How much more does a mortal man need? tongue.gif
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