• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Please critique my room setup plan (kinda long)

klettermann

Member
Joined
Mar 2, 2022
Messages
98
Likes
78
Location
Rocky Mountains
I'm new to serious room equalization, room acoustics, managing room modes, subwoofer placement, etc etc but trying to learn and get started. I've got REW and a USB mike going (mike not yet calibrated but I'll get to that ASAP) and practicing making room measurements, though I'm still struggling to interpret it all. I've alsdo been playing with 'amroc' to try and get a grip on room modes . To add to my confusion, my system has some oddities that would seem to make it the process more complicated. Maybe some of you can critique what I'm doing and what seems to me, at this point anyway, to be a general path forward. Thanks in advance and here goes....
tube Traps
The room: L22 x H7.3 x W12.3 ft,, double sheetrock everywhere, green glue, channels etc. Carpeted floor, cushy couch, ottoman. I've got 4 ASC Tube Trap towers to play with but no toher room treatments so far.

The gear: There are 2 systems that are partially integrated. One is pretty conventional HT system with Denon X3800h AVR configured as Atmos 7.2.2. The other is a 2ch system. These both share the front/2ch amp (very large) and speakers (Maggi MGIIIa's, also very large). Source switching between HT fronts and 2ch is via Schiit Loki Max that then feeds the amp. This arrangement seems to work very nicely. I've got 2 modest subs to play with for the HT sysgtem later.

Goals: My first priority is getting the 2ch system worked out as best I can. It does not have any serious EQ (Loki Max isn't intended for that) and no facility to do any sort of DSP. Presumably that implies getting the MGIIIa's and lisgtening position optimally arranged. I'm happy with the MGIIIa's for 2 ch and see little need for subs on those.When that's done return to the HT system and do my best to optimize that with Audessy.

Results to date: Limited room measurments to date shows pretty lumpy LF response between 40hz and 200hz. There's a broad peak from 50-70hz (+10 dB!) and several peaks/troughs thereafter. I was gratified to see that peaks and troughs coincided almost perfectly with the room modes predicted by amrock, which I guess is what would be expected. Nice.

Where to go next?? I see a kind of sequence here:
  1. For smoothing out bass, playing around with listening and speaker positions to get smoothest response. I guess this would entail lots of freq response measurements in different locations, maybe guided by amroc to the extent possible. Then do the same with the bass traps. Anything else?
  2. Next move on the ringing, echo, etc. I guess this is where the waterfall plots, RT60 etc come into play. For this I'm kind of a trained monkey. I thibnk I can get the plots on REW but not sure how to interpret of whe to do about them other than playing around with difussors, absorbing panels and stuff like that. Suggestions on how to tackle that?
  3. Finally, set up the subs for the 7.2.2 HT system.
I can certainly post graphs as I move along. Again, thoughts, ideas, critiques all welcome. Thanks and cheers,
 
Last edited:
There are a few things you did not mention.

1. How are you planning to implement DSP into the system?
2. Do you have a mic boom stand (and not a mini tripod)?
3. Are you planning to use the subs for 2ch as well as HT? If so, how?
 
There are a few things you did not mention.

1. How are you planning to implement DSP into the system?
2. Do you have a mic boom stand (and not a mini tripod)?
3. Are you planning to use the subs for 2ch as well as HT? If so, how?
Good questions:

1. I'm not planning to implement DSP into the 2ch system. I see no way to do it without more equipment and i don't know what that would be. For the HT system I'll use Audessey on the AVR.
2. Yes, no problem there.
3. No subs for 2ch, only for HT. I'll come to that after 2ch is optimized.

Thanks and cheers,
 
It is worthwhile to run the 2 channel system through the AVR and pre-out into an external amp. Sure, the DAC performance isn't great but EQ + subwoofer integration is simply too valuable to ignore. Passive room treatment that works below 100Hz is bulky, expensive, and still won't completely fix your bass response.

If you don't want the AVR in the signal chain get something like a miniDSP Flex. It has audibly transparent DAC and ADC performance.



As for your spectral decay aka time domain performance a good goal is consistent decay across all frequencies. The most common mistake I see in room acoustics is absorption panels which are too thin. If the treble and mid-range are falling off quickly but not the bass it will aggravate the perception of room modes.
 
There's a broad peak from 50-70hz (+10 dB!) and several peaks/troughs thereafter. I was gratified to see that peaks and troughs coincided almost perfectly with the room modes predicted by amrock, which I guess is what would be expected. Nice.
It's natural and not surprising, but there's nothing nice about it. It presumably sounds boomy.
I would try to do something\anything :) about it. Especially for music.
Measurements allow us to learn more.
 

The gear: There are 2 systems that are partially integrated. One is pretty conventional HT system with Denon X3800h AVR configured as Atmos 7.2.2. The other is a 2ch system. These both share the front/2ch amp (very large) and speakers (Maggi MGIIIa's, also very large). Source switching between HT fronts and 2ch is via Schiit Loki Max that then feeds the amp. This arrangement seems to work very nicely. I've got 2 modest subs to play with for the HT sysgtem later.

Get the 2 channel sounding good, and just moving the speakers around to find good spots should largely do it.
If there are subs for the 2 channel, then that would work as part of that in a second step.

I can stream out of my AVR and there are PEQ setting in there for fixing up the speakers…
I do not know a lot about a Loki, but if the AVR has streaming and PEQs, then could be an option rather than the Loki.
A friend has Maggys, and his seem to like being well away from the walls.

Where to go next?? I see a kind of sequence here:
  1. For smoothing out bass, playing around with listening and speaker positions to get smoothest response. I guess this would entail lots of freq response measurements in different locations, maybe guided by amroc to the extent possible. Then do the same with the bass traps. Anything else?
Sometimes there are positions that are not allowed, like WAF denied ones.
Starting with sensible allowed positions can cut down the options.

  1. Next move on the ringing, echo, etc. I guess this is where the waterfall plots, RT60 etc come into play. For this I'm kind of a trained monkey. I think I can get the plots on REW but not sure how to interpret of whe to do about them other than playing around with difussors, absorbing panels and stuff like that. Suggestions on how to tackle that?
  2. Finally, set up the subs for the 7.2.2 HT system.
I can certainly post graphs as I move along. Again, thoughts, ideas, critiques all welcome. Thanks and cheers,
There could be subs as 7.2.2, and/or there could be subs on the 2 channel.
Personally I would put them on the two channel if possible, but that assumes you have a way to do that.
If you had them on the 2 channel, you could also run som other, subs on the 7.x.x… Maybe the 2-channel is more lore like 40-100 Hz, and the HT side is more LFE, like 15-60 Hz…
 
Back
Top Bottom