[mfsoa]

OK thanks for the clear explaination. I didn't realize the sub amps had stereo inputs.

-Mike

[Joe_K]

Hi Mike,
Seeing what budyog has done and having a pair of Maestros, I will want to pull out the 2ch pre and try stereo subs.
I will try this with a pair of Allison AL-125s, a 3-way system with 2- 6” woofers in a push pull arraignment, -3db = 48Hz; -6db = 38Hz.  I believe the 2nd woofer comes in at around 100HZ on down with a half section (12db/octave?) crossover. The second woofer is reversed to lower harmonic distortion.  I realize I’ll loose some of the benefits of the 2nd woofer, but…
These are about 30 in tall x 11 x11 so copying Budyog’s setup has crossed my mind. i.e.: speakers on top of subs.
I’m interested in your recommendation for Xover F and is the 6db slope of your rca filters steep enough?
I noticed you also have balanced filters with a 12db slope. Can the xlrs on those be used with xlr to rca adapt, or would you loose the extra slope?
Also, would there be any advantage to spacing the subs wider than the main speakers? Or is that back to trial and error? I’m looking at a 25 ft wall with the mains about 10 to 12 feet apart.

Thanks,
Joe

[oris98]

Will the vibration coming from the Maestro sub be transferred to the speaker on top and causing coloration or disortion ?   Most people do is to isolating their equipment from vibrating partners with cones, or with other dampering mechanizm ? 
 

[budyog]

Will the vibration coming from the Maestro sub be transferred to the speaker on top and causing coloration or disortion ?   Most people do is to isolating their equipment from vibrating partners with cones, or with other dampering mechanizm ? 
 

I spoke with Mike Dzurko about to couple or to de-couple. First off, The Maestro's are very heavy and only slightly thump at extreme volume. Very rarely played at that volume and if you are like I have, there are so many other things in the room possibly distorting the sound, you would in no way here anything distorted coming from the speakers in relation to sitting on top of the sub unless your equipment is peaking and sending distortion to the mains.
In my case. I am using a thin rubber no-slip matting under the sub and it works great to absolutely couple it to the floor. It don't move at all! It almost like sucks it down to the floor. Then I am using 1/4 inch thick solid steel I beam about 20lbs, coupled with the same no-slip rubber matting between the I beam and the sub and the I-beam and the Panorama which are is about 60lbs, totally full speaker to floor couplization. No dis-coloration whatsoever! The matting is the stuff that goes under rugs to keep from sliding around the hardwood floor. It works great.
So, to couple or to de-couple. I feel if you can couple to make one that is as good as to de-couple. I did use separate stand and points etc to de-couple before but now with the stereo subs, this setup works super and sounds super to me!
Plus ACI builds such rock-solid inert cabinets , I really don't think it matters that much what their speaks are sitting on!

[Mike Dzurko]

Hi Mike,
Seeing what budyog has done and having a pair of Maestros, I will want to pull out the 2ch pre and try stereo subs.
I will try this with a pair of Allison AL-125s, a 3-way system with 2- 6” woofers in a push pull arraignment, -3db = 48Hz; -6db = 38Hz.  I believe the 2nd woofer comes in at around 100HZ on down with a half section (12db/octave?) crossover. The second woofer is reversed to lower harmonic distortion.  I realize I’ll loose some of the benefits of the 2nd woofer, but…
These are about 30 in tall x 11 x11 so copying Budyog’s setup has crossed my mind. i.e.: speakers on top of subs.
I’m interested in your recommendation for Xover F and is the 6db slope of your rca filters steep enough?
I noticed you also have balanced filters with a 12db slope. Can the xlrs on those be used with xlr to rca adapt, or would you loose the extra slope?
Also, would there be any advantage to spacing the subs wider than the main speakers? Or is that back to trial and error? I’m looking at a 25 ft wall with the mains about 10 to 12 feet apart.

Thanks,
Joe

Joe:

I would use the 6db passive filters, it just seems too much complexity to be using additional adapters and such with the balanced filters. I think the 85Hz would likely be the best overall.

I think what Budyog has done is really cool, especially for saving space. IF you have plenty of space, I still think there is the potential advantages to placing the subs separately of being able to experiment with the placement of the subs to get the smoothest in-room bass response.  So, yes, you're right, I would certainly experiment with sub placement if I had the flexibility to do so . . .  sometimes just a little move can make big improvements.

[budyog]

I forgot to mention. The wife factor!  If I have 2 subs the size these are, I cannot have them just placed anywhere! This is the living room! It might be different if I had a separate listening room, but I don't think I would change it. It really sounds great! I would probably keep them the way I have them. I feel it keeps that true stereo sound  I like. aa

[Mike Dzurko]

Three generalities that should be considered.

1) The closer the subs are to the mains, the easier it will be to get seamless integration. Adjustment is not quite as touchy when the subs are under or right next to the mains.

2) Placing the subs under or adjacent to the mains might not yield the smoothest bass response possible. Optimum sub placement can be modeled with software, but generally requires actually moving the subs around the room and listening and if possible, measuring.

3) Placing the subs adjacent to the maximum # of room boundaries, I.E. the corners, will yield the maximum output levels and often provides a pretty smooth response as well. But, see #1, this may require the most tweaking of the controls to get best integration. Also, just moving the sub a couple inches out in either direction might be advantageous. In a sense, the corners provide free bass capability. However, if you have more than enough air moving capability for your room, (twin Maestros in Budyogs room certainly counts), the advantages of the corner probably don't need to be considered.

Being generalities they are NOT absolutes, but might help someone trying to decide on initial placement.  For a lot of people, the best move could be to start with the subs under or very close to the mains. Get this dialed in and you will at the least, have great integration and good bass response. If you want to seek even smoother and or more potent bass response, experiment with sub placement.

[Joe_K]

Thanks Mike and Budyog for the info and advice.

Mike, I'll try the 85Hz filters w/speakers on top of subs and go from there.

Budyog, Can you recommend any disc(s) with lots of low stereo bass, or that demo low stereo bass?

Thanks,
Joe

[budyog]

Hey Joe,
  I will think of what I have and reply soon.

[mfsoa]

Bela Fleck and the Flecktones "Flight of the Cosmic Hippo" is one of the classic bass torture tests.

[budyog]

Watched 2 good movies this weekend, and did they sound great!
Saturday night was “Night at the Museum” I like this movie! Fun and entertaining, but the sound was fantastic! I felt low bass that seem to roll across the floor in waves when the T-Rex would run around. A good one for stereo subs. You could feel the movement from one side to the other. And when all the animals were running around, We were immersed in sight and sound!
Sunday night was something totally different! “Letters from Iwo Jima”. All subtitles. Another very good movie if you like movies about war. Very well done, very moving and again, great sound, another one where stereo subs seem to come into play. When you heard or saw explosions in the picture off to one side or another, you could feel the low wave/aftershock come from that side of the room. Even the gun shots were tight and real sounding.
The only small thing about the movie is you could tell the computer generated ships at sea, but understandable. I do not think it could be done any other way. We probably do not have enough ships in our fleets!
I feel I must  have things dialed in pretty good. I do not seem to want to change a thing!
I will update my gallery pictures with my new TV soon.