These work nice if you want to use with your iPhone or iod apps. Just use one of their camera kit adapters. You can also load your microphone cal file in most apple apps.
Thank you for the feedback. I was biased to the AVAA solution simply because of the technology. Long term I sense there will be at least one of these in my listening space.
I did the same thing. I took it out of the box and then forgot all about it. But I think I could find it if driven to do so.
I got REW working and here is a waterfall graph from my seated ear height listening position - promise not to laugh, I had no idea I have such a null between 58-62Hz.
This is with C214 OFF:
And here is C214 ON:
It looks like I need to buy more things - like subs too…
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I see a couple of mentions of the MiniDSP microphone and REW, for anyone trying to use this combo there are a couple of REW tutorials on the GIK website that get you right to what you need for checking room performance. I found them a lifesaver since REW has a lot of options. The one I used is here. There is a second one but it is about ten years old, so probably out of date.
Would I be nasty if I said I detect no difference? I am thinking of saying that. I’ll schedule saying it for later.
Don’t ask me to do that with the Black Box.
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The biggest difference I see in the graphs is in the decay time in the 28-40Hz range. According to REW there is a lot of ringing/decay going beyond 300ms shown in the OFF graph - I’m trying to figure out how to drill down in the REW graphs to see how far beyond it goes. With the C214 ON the majority of the decay times have been reduced to less than 300ms. Second thing I picked up on is what looks like about a 2 to 3 dB reduction in SPL in the 28-40Hz range.
I won’t ask you to do that with the Black Box - even though I might try - but I have a feeling that will be more difficult to have a machine acknowledge that we can hear a difference. Darn machines think they have to validate us humans. Am I raging against the machines?
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Thank you! You made your microphone work, something I have safely avoided. With your comment I now easily see the obvious difference. Glad I held off on making my statement!
It is clear then that the device only affects the bass?
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Excellent work, Mark. Thanks. Yes I can see the reduction from 40Hz down. Could you also post the 1/3 or 1/6 octave smoothed FR and the RT60 plots? For FR use the ALL SPLs tab so we can see the FRs overlapped on each other. The waterfall is amazingly good even without the C214 in a 12x15 foot room, although I think that 18 foot ceiling may have a lot to do with that. Thank you!
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If the MiniDSP mic has a text or csv calibration file and can be seen by REW it should be usable with no issues.
Tony, I think you may have read more into my post than intended. My previous experience with making room measurements was a Radio Shack meter and some rudimentary knowledge. Didn’t help me much other than finding peaks and nulls. So I needed something more, REW was the recommended choice.
When I first got the MiniDSP and REW I was a bit overwhelmed by all the capabilities. I wasn’t confident I was getting useable data. When I started looking closely at the GIK treatments I found their REW tutorial. With that I was able to produce something useable to me and them. Fast forward to this discussion, when I saw hardlyknow1’s comment on not having set up REW I thought I would let him, or anyone else in the same situation, know about the GIK tutorial. That’s it …
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I was thinking the same thing and then his explanation made things clear. Bass vacuum cleaner.
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A bass vacuum cleaner is a good way to describe it, and based on my room results its primarily low bass. Who knows what algorithms PSI Audio is spinning in their DSPs but they do appear to leave the higher frequencies untouched.
I decided to relax today and just enjoy the music and not do comparative/analytical listening - it was beginning to remind me of what I did for a living, work. So I brought the Black Box back in the room for some r&r and it added to my enjoyment.
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I am really curious to see the plots of the Black Box in and out!!!
You are doing great work sir!
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Thanks
Using REW yesterday reminded me of why I don’t like wrestling with PC apps. Just a word of advice if you do fire up your microphone, keep your finger off your mouse wheel if you’re looking at REW graphs unless you know specifically what it will do. I spent more time trying to figure out how to undo my unintended wheel movement then anything else (this was after I posted the graphs so the graphs are from the default settings).
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You might just inspire me to give REW a shot.
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I heard the PSI units briefly at a show. The thing that struck me was when going to the next room, the bass leaking from the PSI room was huge. So while canceling for the listening position, it may very well add to bass outside the room. Just a thought to possibly be aware of.
Mark, if you saved both of those sweeps in the same mdat file, find a way to post it somewhere where I can get to it. I can do all the messy stuff for you. 
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Go to around 20 minutes into the video for a good summary of the waterfall differences in a small room using the older AVAA product. “You would need a s**toad of bass traps” to get the reduction in lower bass. Nice comparison before and after using the AVAA product.
I need to convince my wife c214 is really an air purifier to get into my house. It has a better chance than that black box for sure.
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