Placement options – Impacts of location, orientation and treatments
- Thread starter JonFo
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Front of Room
And finally, the front of the room.
You can see the big Mondo trap laying on top of the screen support frame over the center channel.
The side MiniTraps are still not permanently mounted, so are leaning against the side walls in this shot.
The wall behind the screen is covered solid with 4 MiniTrap HF's and the doors to the equipment room each have a MiniTrap HF also hung on them.
So there's a good bit of bass trapping as well as High Frequency absorption back there.
And finally, the front of the room.
You can see the big Mondo trap laying on top of the screen support frame over the center channel.
The side MiniTraps are still not permanently mounted, so are leaning against the side walls in this shot.
The wall behind the screen is covered solid with 4 MiniTrap HF's and the doors to the equipment room each have a MiniTrap HF also hung on them.
So there's a good bit of bass trapping as well as High Frequency absorption back there.
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Now, some before and after waterfall plots. As these are the most telling as to the impact of the treatments.
First, the before. Both of these are using 300ms windows to show the mid-bass and bass regions.
Notice the many and long lasting mountain ridges in this shot, highlighting the fact that there are both many resonances, and that their duration is extensive. Not good.
First, the before. Both of these are using 300ms windows to show the mid-bass and bass regions.
Notice the many and long lasting mountain ridges in this shot, highlighting the fact that there are both many resonances, and that their duration is extensive. Not good.
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And the after.
In this one we can see that most resonances are totally gone, the only frequency with resonances out to 300ms is somewhere around 18hz and a very narrow resonance right under 300hz, but at very, very low levels, so no worries.
Notice how most everything is damped by around 100ms, which means we can now hear the bass notes clearly without the room coloring the sound excessively.
Mucho better.
In this one we can see that most resonances are totally gone, the only frequency with resonances out to 300ms is somewhere around 18hz and a very narrow resonance right under 300hz, but at very, very low levels, so no worries.
Notice how most everything is damped by around 100ms, which means we can now hear the bass notes clearly without the room coloring the sound excessively.
Mucho better.
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I still need to work on EQ’s and rebalancing the gains.
But that will wait for later.
But that will wait for later.
MiTT
Super User
Very impressive Jon. Forgive me if I missed this somewhere earlier in the thread, but what would you say the budget for this type of treatment came out to? I'm starting to work on my own dediccated room and want to be certain I allocate appropriate funds to do it right.
Thanks for posting this thread!
Thanks for posting this thread!
Ethan Winer
Well-known member
Excellent Jon, thanks for posting all that! :bowdown:
Beautiful work, Jon. The comparison of those two waterfall plots says a lot, but I know even that doesn't tell the whole story of the improvements you are hearing. I must say, going with the black traps in that room with all the dark colors you already had, there is very little visual impact from all those traps. Nicely done.
Hi Tim, thanks, and you're welcome.
The Realtraps alone were $7K (delivered), plus the existing RPG (ProFoam, Skyline and Bass traps) were another $2 or $3K on top of that.
I still need to do DIY side treatments, and the ceiling will need some work as well. I'm sure one of my few remaining mid-bass resonances is due to the untreated ceiling. I have some interesting ideas to combine treatments + a height channel up there (hey, got to do something with that 'left-over' SL3
). Also, I put in power and a speaker cable when I built the room, so time to do something with them.So I figure to do a room this size with all commercial tools, one should budget around $10 to $12K.
Considering what some of us on the board will spend on amps and cables, I can assure you that this class of investment in acoustics has a much bigger (and instantly noticeable) audio ROI
Hi Ethan, well thanks to you for these great products. Obviously quite effective in their purpose.
I will be adjusting EQ's today. Specifically the sub to notch out that 18Hz mode.
But some tweaks here and there based on averaged multi-point measurements, Luckily RD has a very nice filter predictor included in it.
Thanks Rich. Yes, since you've seen this room, you know that nothing shows up if it's dark and on the ceiling.
Those pictures are totally artificial, when in the room, you really do not see anything significant.
I was a bit nervous at first about so many treatments in the room, but now that everything is installed, the only 'obvious' ones are the big 8' stacks of Mondo traps in the rear corners. But then again, they are in the rear. So no big deal.
The improvement in sound (so far) is nothing short of amazing. I keep replaying some of my favorite music just to hear all the nuances I had been missing.
Took a few more measurements this afternoon as I tweaked the EQ's on the Center and Sub.
As noted earlier, the need for EQ is almost gone. I went form seven parametric EQ's on the sub down to three. And could of gotten away with just two. That's pretty impressive.
So here is a frequency response plot of just the sub from the main listening position (at 6 meters).
The red trace is before EQ and the green is post EQ.
Notice how the bumps at 63 and 21 are attenuated by the EQ. This will also be reflected as reduced resonances in the waterfall plot.
Also of interest is how the 18 to 80 hz range fits in a tight (for in-room bass) window of +/-4db.
This is what you are buying with this many and this quality of acoustic treatments.
Oh, and these measurements were done at 89dB, which is pretty loud, as I wanted to see if the energy was really being managed well at reference levels.
As noted earlier, the need for EQ is almost gone. I went form seven parametric EQ's on the sub down to three. And could of gotten away with just two. That's pretty impressive.
So here is a frequency response plot of just the sub from the main listening position (at 6 meters).
The red trace is before EQ and the green is post EQ.
Notice how the bumps at 63 and 21 are attenuated by the EQ. This will also be reflected as reduced resonances in the waterfall plot.
Also of interest is how the 18 to 80 hz range fits in a tight (for in-room bass) window of +/-4db.
This is what you are buying with this many and this quality of acoustic treatments.
Oh, and these measurements were done at 89dB, which is pretty loud, as I wanted to see if the energy was really being managed well at reference levels.
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Waterfall of Sub only
And here's the waterfall plot for the sub, post EQ.
Note the rapid (for low bass) decay.
I could still dial down a bit of the output at 20 hz, by widening the Q of the EQ and lowering it a dB or two more. That would mitigate that infrasonic resonance.
And here's the waterfall plot for the sub, post EQ.
Note the rapid (for low bass) decay.
I could still dial down a bit of the output at 20 hz, by widening the Q of the EQ and lowering it a dB or two more. That would mitigate that infrasonic resonance.
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And finally, a PsychoAcoustic frequency response of the Center channel, full range, both before treatments and after.
The blue trace is the Center, behind the screen, taken with no EQ and minimal old treatments. Not so pretty, yet it sounded worlds better than the Logos.
The red trace is the same location and speaker, but with the new treatments in place, and a touch of EQ is also in effect. We now fit a +/- 6db window from 20 to 6Khz. From there on up, we have a typical ESL drop off, as well as losses from being behind the screen.
This is excellent results for in-room performance!
The blue trace is the Center, behind the screen, taken with no EQ and minimal old treatments. Not so pretty, yet it sounded worlds better than the Logos.
The red trace is the same location and speaker, but with the new treatments in place, and a touch of EQ is also in effect. We now fit a +/- 6db window from 20 to 6Khz. From there on up, we have a typical ESL drop off, as well as losses from being behind the screen.
This is excellent results for in-room performance!
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sleepysurf
Well-known member
For those of us struggling with WAF while trying to employ bass traps, here's an interesting new pedestal bass trap design. They are offering it in a variety of fabrics and finishes. More info here...
http://www.gikacoustics.com/gik_elite_pillar.html
I showed it to my wife, and she actually didn't cringe... I consider that tantamount to full approval!
http://www.gikacoustics.com/gik_elite_pillar.html
I showed it to my wife, and she actually didn't cringe... I consider that tantamount to full approval!
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Definitely that is true. But it would look darn good in the corners, maybe with a nice lamp on top.
