Integrating 2 subwoofers

[sidvee]

Guys I will be getting a svs sb2000 soon to partner with my svs sb12nsd for my modest HT. Receiver is a Marantz 6009 which has twin subwoofer o/p and I plan to use the audssey auto calibration to integrate the 2 subs. Planned Placement will be approx 1/3 of room length on either side of viewing area of a 14 x 12 foot room, located closer to listening position. Not too much flexibility with placement as the front wall where speakers are has a large rack containing my 2 channel components. Available walls are other 3 and the plan as described above is to use the 2 side walls. Any pointers/pitfalls to plan for. Kindly advice.
Room Lxwxh 14x12x8.5
Listening position from rear wall about 1.5 feet.
Well treated room all corners have GIK 244 panels as bass traps which are good for 80hz approximately.
In the past calibration with audyssey I felt bass was slightly lower, but now I am fine with the setting as it is subtle but when required really tight and deep.
Cheers,
Sid

 

[ttarasu]

Can we add two different subs(Onkyo & velodyne) to AVR
Thanks

 

[sound_cycle]

I plan to use the audssey auto calibration to integrate the 2 subs<snip>Listening position from rear wall about 1.5 feet<snip>I felt bass was slightly lower, but now I am fine with the setting as it is subtle but when required really tight and deep

:thumbsup:

three (very green and wet behind the ear) points

1) I *think* I am having all kinds of image loss issues because a) proximity to rear wall (Sound travels about 13.5 inches per ms, and 18 inches you mention works out to under 2ms)

2) I have now figured that centre of my LHS ceiling cloud is about 18 - 20 inches short of ideal

3) REW to confirm the result maybe ? The latest version seems to have some tools for reviewing sub integration. Would also suggest a Dirac vs audssey faceoff type experiment (the 15 day trial is free and ATM it is my favorite software)

ciao
gr

 

[karthi1000]

hello sir i am using two subs...... plz go through this
http://www.hifivision.com/speakers/55048-rythmik-fv-15hp-big-boy-black-beauty.html

 

[sidvee]

:thumbsup:

three (very green and wet behind the ear) points

1) I *think* I am having all kinds of image loss issues because a) proximity to rear wall (Sound travels about 13.5 inches per ms, and 18 inches you mention works out to under 2ms)

2) I have now figured that centre of my LHS ceiling cloud is about 18 - 20 inches short of ideal

3) REW to confirm the result maybe ? The latest version seems to have some tools for reviewing sub integration. Would also suggest a Dirac vs audssey faceoff type experiment (the 15 day trial is free and ATM it is my favorite software)

ciao
gr

For item 1 I use a echobuster panel behind my listening position. Helps in getting rid of reflections and cleans up the sound tremendously. If you are sitting close to rear wall absorption is highly recommended, especially directional high frequencies.
Item 2 - not sure, I use the first reflection point of my drop ceiling, and that is treated with a echobuster panel as well.
Item 3 - I am fairly confident of using audyssey, but looking for placement options mainly.
Cheers,
Sid

 

[sound_cycle]

Item 3 - I am fairly confident of using audyssey, but looking for placement options mainly

I understand (no direct experience) the RTA feature of REW is well suited for the task (but then again no idea if audyssey has a similar feature)

wrt rear wall, i have panels on the rear wall, but see some sub 5ms reflections of mysterious origin in the ETC plot. (to re-examine for misinterpretation too)

ciao
gr

 

[sidvee]

Ok thanks Karthi. I read through your thread. I plan to do mostly everything similar to you except for placement, which will be to the sides as described and ofcourse I am using Audyssey Mult EQxt. to dial in the subs.
Cheers,
Sid

 

[sidvee]

So I got the 2 subs placed to the sides of my listening position 1/3 the room length closer to listening position. I set phase as 0 for both, equal gain and disabled the onboard x-over. I did the Audyssey calibration (after which I manually changed speakers to small and x-over to 80hz for all speakers as recommended by audyssey) and sat down for a listen. Definite improvement over single sub. I can feel more impact of explosions and such and a lot less localization cues. Before with one sub I could feel the bass emanating generally from the spot in the room where it was located (though receiver x-over was set to 80hz). Overall I am very satisfied. Now to experiment with different positions on the side walls to hear which will sound the best.
Cheers,
Sid

 

[hydrovac]

Guys I will be getting a svs sb2000 soon to partner with my svs sb12nsd for my modest HT.
Sid

Sid,

You have a good plan in place... according to SVS literature, single SB12-NSD would be adequate for your room of under 2000cft. So, any specific reason, or rather your goal in adding a second sub... SPL, smooth out room modes?

I set phase as 0 for both, equal gain and disabled the onboard x-over. I did the Audyssey calibration (after which I manually changed speakers to small and x-over to 80hz for all speakers as recommended by audyssey) and sat down for a listen.
Sid

You are trying to gain match two non identical subs with different gain structure and power output how will this translate into level matching, are you going to trim from AVR?

Are you sure that Audyssey MultEQ in your AVR is capable of setting independent levels for two subs which calibrates and does phase, EQ on each one independently, then calculate it as a pair/mono did you see an increase in SPL? Otherwise it sounds like a good setup.

From what I understand, you should consider dual of identical subs.

For a noob myself, sounds like it's quite a job to get their placement right and setup/calibrated so they do not cancel each other out how hard is it really? And what equipment do you need?

Pardon my ignorance and too many questions... will help me guide in my HT

Cheers!

 

[sidvee]

Sid,

You have a good plan in place... according to SVS literature, single SB12-NSD would be adequate for your room of under 2000cft. So, any specific reason, or rather your goal in adding a second sub... SPL, smooth out room modes?

You are trying to gain match two non identical subs with different gain structure and power output how will this translate into level matching, are you going to trim from AVR?

Are you sure that Audyssey MultEQ in your AVR is capable of setting independent levels for two subs which calibrates and does phase, EQ on each one independently, then calculate it as a pair/mono did you see an increase in SPL? Otherwise it sounds like a good setup.

From what I understand, you should consider dual of identical subs.

For a noob myself, sounds like it's quite a job to get their placement right and setup/calibrated so they do not cancel each other out how hard is it really? And what equipment do you need?

Pardon my ignorance and too many questions... will help me guide in my HT

Cheers!

Hydrovac,
I myself am a novice so I will try to answer as best from my limited knowledge.
1. I wanted to upgrade my current sb12nsd, but I decided on a second sub. to help in smoothening out of room nodes rather than buy 1 expensive sub. which by the way is mostly recommended.
2. However sb12nsd had been discontinued so I had to choose its replacement the Sb2000. It has slightly more power but cabinet/driver size are exactly same. Yes it would have been ideal to get another nsd or sb2000 but no choice. I read that this is not a huge deal breaker provided both subs are similar size and from same manufacturer (I am not sure if this is right but my experience in point 4 shows that it is fine)
3. I am using the Marantz 6009 with Multi eq xt and dual sub outs. With a single sub I was initially sceptical about Audyssey but eventually I realized that it is quite good, better to my ears than manual adjustment.
4. I think the most important thing about 2 subs is placement. So far I have tried 1 setting as described in my previous posts and used Audyssey calibration. In my listening position I perceived increased SPL levels rather than single sub and more tactile effects than before. Yes I let Audyssey do all the calibration, I simply set the sub gain levels of both at 11'o' clock, turned off cross over and kept phase at 0.
5. Now I am going to try another recommended position subs at 2 opposite corners of the long dimension of the room - the 2nd option in the link below.. Best option as I have read is to put 2 subs halfway on the shorter wall opposite each other. This option won't work for me as I have a big equipment rack on one side.
http://www.audioholics.com/subwoofe...er-placement-the-place-for-bass-part-1-page-6
Hope this answers some of your questions.
Cheers,
Sid

 

[sidvee]

Now I am going to try another recommended position subs at 2 opposite corners of the long dimension of the room - the 2nd option in the link below.

Ok I tried this positioning, both subs at diagonal corners of my room. Both sub levels at 12 'o' clock, x-over off and phase 0.
Ran Audyssey. It set the rcvr. sub level at -12db (initially I though this was low). Over the weekend I saw the horror movie "The Conjuring". Wow! There were loose stuff in the room that were vibrating and rattling, something the single sub never achieved and even 2 subs at the sides didn't. I am assuming I am getting corner placement boost that is smoothened nicely due to 2 subs without creating the dreaded boom. Anyways very satisfied now. I think my placement experimentation is done.
Cheers,
Sid

 

[hydrovac]

Ok I tried this positioning, both subs at diagonal corners of my room. Both sub levels at 12 'o' clock, x-over off and phase 0.
Ran Audyssey. It set the rcvr. sub level at -12db (initially I though this was low). Over the weekend I saw the horror movie "The Conjuring". Wow! There were loose stuff in the room that were vibrating and rattling, something the single sub never achieved and even 2 subs at the sides didn't. I am assuming I am getting corner placement boost that is smoothened nicely due to 2 subs without creating the dreaded boom. Anyways very satisfied now. I think my placement experimentation is done.
Cheers,
Sid

Great job, and good summary Sid!!

Corner loading will gain an extra 3 to 5dB... will permit you to turn the levels down, to have more head room with lower distortion and a more linear range of driver excursion.
The trade off with this placement is that you lose the flat FR... giving Audyssey a more battered curve to work with.
Let me ask you this: If you play just the closer sub, can you hear it as a localized source of sound?

 

[sidvee]

Let me ask you this: If you play just the closer sub, can you hear it as a localized source of sound?

Haven't tried that Hydrovac. Will check it out.
Cheers,
Sid