Bass Traps

tcutter wrote "@kr4 can I place the PSI AUDIO AVAA C214 directly behind the couch of my sitting area or on your experience is it better to keep it upfront.  I can probably only do 1 unit now and a 2nd one later

Not likely. 

fire_water wrote: @kr4 can I place the PSI AUDIO AVAA C214 directly behind the couch of my sitting area or on your experience is it better to keep it upfront.  I can probably only do 1 unit now and a 2nd one later

Probably not.  They need to be placed where there is the highest pressure due to room modes and these are generally at boundary intersections.

@kr4 

I was inquiring as to the advantages of adding the AVAA to a distributed bass array (DBA). When I reviewed Bob Katz' Stereophile article back in 2016 (https://www.stereophile.com/content/psi-audio-avaa-c20-electronic-bass-trap), it appeared that the improvements were on the order of 2 dB or less, which seemed small in comparison to my DBA's impact. Your article (https://www.stereophile.com/content/psi-audio-avaa-c214-active-bass-trap) seems to emphasize decay times and indicate the device(s) might still be of benefit. 

I recognize you reviewed a later design, but I get the impression the performance is virtually the same and it was primarily a cosmetic move, along with a control or two.

I have no first-hand experience with DBA or with the C20.  However, according to PSi, the C214 is more efficient (and well as better looking) than the C20 and one would have predicted a more pronounced effect than shown by Katz.  Nonetheless, my FR measurements with the C14s were consistent with Katz' and did not seem to correlate with the audible effects which were immediately apparent to me.  That motivated me to examine decay times.

@OP I have experience of both products. The Synergistic box, at best, does nothing. If you look at it in the context of the laws of physic, that's not surprising.

The PSI AVAA C214 is a completely different animal. It is highly effective and the effect is readily audible. It takes a little bit of time to fine tune placement and the gain adjustment. When dialled in it is very effective at smoothing out the bass and has consequential effects up into the midrange.

While I'm a happy custoemr of GIK, another good source is ATS Acoustics.  Also always worth checking the AM Acoustics Room Mode Simulator for help understanding your problems and tips on speaker/listener positions