PSI AVAA

[Soniclife]

Where’s Savage?
AVAA update, they work ( ish) you would need to try them in your own room.
Keith

That sounds a less than ringing endorsement. Any measurements?

 

[Purité Audio]

I have made some in one room, I just want to measure their effect in our other room, but it looks like four units would be a minimum in our 6 x4 metre room.
Keith

 

[stunta]

So this absorbs the sound and converts it into what? Heat? Mechanical energy?

 

[pos]

It cancels it, so you can consider it turns it into heat, depending on the efficiency of the AVAA

 

[Purité Audio]

I added a few photographs to the PSI page,
https://www.puriteaudio.co.uk/weiss

measurements and that all so important subjective impression to follow.
Keith

 

[flipflop]

Still waiting in anticipation for those measurements

 

[pierre]

Still waiting in anticipation for those measurements

I have found https://www.gearslutz.com/board/stu...st-results-psi-avaa-c20-active-bass-trap.html

The change in the waterfall is noticeable.

 

[andrew]

I added a few photographs to the PSI page,
https://www.puriteaudio.co.uk/weiss

measurements and that all so important subjective impression to follow.
Keith

Any updated? It'd be interesting to understand the advantages / disadvantages of bass traps vs AVAA-C20 vs multiple subs. I get that it's impractical to have bass traps for very low frequencies (although perhaps Helmholtz traps will work) but - other than plug-and-play - am unsure as to what the AVAA-C20 delivers that cannot be done with well set-up subs. Is the value in ease of set-up? Or is there something else?

 

[Purité Audio]

Well they do work, but you probably need at lest four of them, which is going to be expensive.
They are neat though, far less intrusive than resonators/membranes etc.
Keith

 

[andrew]

Well they do work, but you probably need at lest four of them, which is going to be expensive.
They are neat though, far less intrusive than resonators/membranes etc.
Keith

What, given this, is the advantage over adding multiple sub-woofers? I guess that it's better decay time?

 

[Purité Audio]

PSI at Purité Audio,
https://www.psiaudio.swiss/

Keith

 

[Bjorn]

Are you aware of how many bass traps like the RPG Modex Plates you could buy for the amount you're paying for these? And those would work in a much broader frequency area and the end result should in most cases be far better.

 

[Purité Audio]

I already use Modex tuned membrane, for the specific ( length ) room mode.
The science is sound I believe, I wanted to see what they would do.
Keith

 

[Bjorn]

Modex Plate isn't the same as the tuned Modex membrane. With the membrane though, you need several for a good result as with all bass traps that works below 100 Hz.

 

[Purité Audio]

I have some of these,
http://www.rpgeurope.com/products/product/modexplate.html
These,
http://www.rpgeurope.com/products/product/modexcorner.html
And some of these,
http://www.rpgeurope.com/products/product/modexmodule.html
They do work, you just need a large area, and they aren’t exactly cheap.
Keith

 

[Bjorn]

No, they aren't cheap but cost much less than the AVAA bass trap. My point was that with cost of the AVAA you can buy several Modex Plates, address a much broader frequency area and the end result would in most cases be better.

The AVAA should be more effective at one frequency though, since it's active and can be dialed in. But addressing only one or two very shallow areas is seldom a good way to treat a small room since you have multiple room modes. Broadband is almost always a better way.

The Modex Corner probably doesn't work very well by the way, because it's not covering enough surface. And I alsways recommend the larger Modex Module (120x60 cm) over the smaller one (60x60 cm). People often forget that wavelengths have size when treating a room.

 

[JIW]

There are some new measurements of the AVAA C20 made by Sound & Recording. As this is only the preview showing the data without going into detail about the setup and method, I cannot say exactly how they were made. The full article explaining this is in Sound & Recording 11/2019.

From what I can tell, they seem to be made in their listening room which they use for subjective evaluation of speakers/monitors

with theoretical frequency response at presumably the listening position in the frequency range of interest (~ 0 to 500 Hz)

I: Pressure regime, II: Resonance regime, modal structures, III: Statistical regime, diffuse sound field.
Room: 6.2 x 3.4 x 2.5 m (L x W x H) (Volume = 52 m^3) with RT = 0.2 s.
From I to II at 27.5 Hz (wavelength = 12.4 m)
From II to III at ca. 125 Hz

Frequency response of (multiple, presumably two) Neumann KH310s at listening position with (red) and without (blue) AVAA C20

Spectrogram of (multiple, presumably two) Neumann KH310s at listening position without AVAA C20

Spectrogram of (multiple, presumably two) Neumann KH310s at listening position with AVAA C20

Frequency response of subwoofers (unspecified but according to figure text multiple) at listening position with (red) and without (blue) AVAA C20

Spectrogram of subwoofers at listening position without AVAA C20

Spectrogram of subwoofers at listening position with AVAA C20

I got access to the image links through the source code since the links are not accessable for me directly through the website.

 

[oivavoi]

Thank you very much for posting this! Very interesting. Impressive in many ways. But wouldn’t one be able to achieve much of the same result just be some eq in the bass and taking down the extra energy in the peaks? It seems strange to me that they had that big peaks using multiple subwoofers... they can’t have used any eq before putting the Avaa in place it seems.

 

[pozz]

Thank you very much for posting this! Very interesting. Impressive in many ways. But wouldn’t one be able to achieve much of the same result just be some eq in the bass and taking down the extra energy in the peaks? It seems strange to me that they had that big peaks using multiple subwoofers... they can’t have used any eq before putting the Avaa in place it seems.

Multiple subs don't guarantee even response across the room and won't fix room modes, even if they do redistribute standing waves. It's a physical problem that can't be fixed with EQ. If you try to boost, null will get deeper. If you take everything down, it won't affect the ringing at all.

It's basically their speaker drivers mounted in a box with a microphone, working in reverse.

A presentation/lecture on it is here:

 

[Soniclife]

It's a physical problem that can't be fixed with EQ.

News just in...
https://audiophilestyle.com/ca/reviews/home-audio-fidelity-room-shaper-review-r855/