Intro
Contents
At Alpha Audio, we often say that your room is responsible for half your sound. And that’s no exaggeration. Put your hi-fi system in a different room: it will play completely different. This is one of the reasons why we applaud the emergence of aesthetically pleasing acoustic products. Including the PSI AVAA C214: an active bass trap. Yes!
In 2018, Alpha Audio took a ‘hi-fi road trip’ through Switzerland. An unforgettable experience. During that audio trip, we also visited the Swiss PSI. There we had a good opportunity to see how the brand operates and what they were working on. And there was also the ‘studio version’ – THE AVAA C20 – of this new AVAA C214 operating in a small demo space.
The demo at PSI itself was already pretty convincing, but – we think – we were still dealing with an early version or maybe even a prototype. However, the whole concept of the AVAA intregued us. It never left the mind of your author.
If we can actively control the bass with a compact system, that would be great! It saves large, expensive bass traps that basically nobody wants: it takes up space, can’t be moved, and so they tend to be pricey. Although the AVAA C214 isn’t exactly cheap either at 3400 Euros.
How does a PSI AVAA C214 work?
Basically, the AVAA is a microphone with an active speaker attached to it. The microphone measures the room-mode and the amplifier plays it “out of phase”. As a result, the room-mode is absorbed.
Of course, it is terribly difficult to do that properly. After all: it has to be real-time, otherwise you’re always too late. Also, you must not absorb too much or too little and not take away information that is part of the music.
PSI explicitly reports that it does not work the same as noise cancelling. The unit “absorbs” room modes by moving with the pressure waves. It does not actively play anti-noise. By moving with the pressure wave, it absorbs energy. However, it does not color the playback. A very big advantage. More on that later!
The PSI AVAA C214 – like the AVAA C20 – operates between 15 and 150 Hz. Whereas the C20 did its work completely analog, the new C214 is fitted with a few gadgets. It can be controlled with an app – more on that later – and it has been made more compact (round, but it does not work omnidirectionally!), which is possible thanks to the help of very sophisticated, low latency DSPs (there are two DSPs in it). Additional advantage: the gain is now adjustable (both with buttons on the device, and via the app).
Installation
Installing the PSI AVAA C214 is child’s play. Basically, all you have to do is plug it in and flip the switch. The AVAA is already doing its job just fine. However. we have found that proper placement does have quite an effect.
What we did was walk around and see where the bass energy was getting problematic. There we placed the AVAA and then adjusted the gain. And that works like a charm. You can really hear an immediate effect.
App? Uhh…
Now there is an app for the new PSI AVAA. This app allows you to create groups and control the gain. This can also be done with the buttons on the back of the AVAA. And since the gain only needs to be set right once, we don’t really see the app as a must-have. fortunately, because…
we ended up not installing this app because it requires having a separate 2.4 GHz network. The Wi-Fi network at Alpha is controlled by a Wifi controller and works on 2.4 and 5 GHz (band steering). On which band our phone is connected, the controller decides. New Android phones no longer allow manual switching either. In short: we could not connect to the AVAA. Case in point for PSI, because we won’t be the only ones…
The Hans Beekhuyzen Channel
Improving lows with the PSI AVAA C214 active bass trap
https://www.youtube.com/watch?v=xYIgoUnr8ME
Nice video!
Interesting, as I use stacked ASC tube traps in one corner and singles directly adjacent to and on the outside of my main (ATC) speakers, all for about 2/3 the cost of the PSI. Not the best design for company. With the PSI, it’s not clear from text or photos where they ended up. It’s hard to imagine that placement in the middle of the room, as two of the photos show, will sell well.
Those AVAA’s are placed to the side, out of sight. The image is, well, to photograph the AVAA’s.
You place the AVAA’s where the room-mode is problematic. That way, it works the most efficiënt. It works in a different way than a bass trap that is mostly installed in a corner.
How many did you test and how big was your room?
We used two of them. Our room is treated and 50m2.
How many? At least two Psi AVAA C214? -> $$$
It works with one… we used two. The effect is incredible.
Interesting product especially if you do not or cannot use room treatment devices. Thank you for this review, but may I make a suggestion that your readers might find useful. After decades of experimenting in getting rid of the annoying lows (and applying all sorts of passive and active devices) I ended up with an effective but very affordable combined set up. After measuring the room I stacked Big and Small Blocks in the corners. I placed single SiRRAH ‘cushions’ on the first reflection points on the walls and behind the Voxativ Field Coil full range units. The speakers are open baffle PAP Quintet 15 with four 15″ bass drivers per side. After this treatment there’s still a bit of a peak in the ‘famous’ 60-65 Hz region veiling the lower and mid frequencies. For that I used Roon which is in my Grimm Mu1. I created a quite steep filter around 60 Hz thereby removing a larger part of the peak, which gives you this ‘veil removing’ affect. At the same time I boosted the 20-35Hz band with a gradual slope effectively filling out the low end of the bass. My amp can easily pump out the boost when speaker resistance drops beyond 4 Ohm. This DSP solution is effective and very pleasant and for free as it is a part of Roon anyway. AND you can play with it to your hearts content or even create multiple ‘solutions’. It will not replace proper speaker placement and basic room treatment for the bass, but it is the icing on the cake and for free. It will enhance perceived resolution and stereo image big time. The trick is, and I cannot emphasize this enough, not to try to correct ‘everything’. Small steps go a long way. I keep saying you need to take care of the room FIRST instead of constantly swapping gear, tubes, cables et cetera. Enjoy!
Dear D.L. Whitton, I use an Auralic Aries G1 with which I can also influence the frequency. I was already experimenting. With your additional information I will try to take a step forward. Thank you. I’ll let you know.