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PSA/miniDSP measurement microphone

PaulyT

PaulyT

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Ok this is actually pretty cool:

:text-link:

UMIK_1_3db58dc5-d269-4aa3-96f9-5a2642077f27_1024x1024.png



A USB-direct measurement mic, saves the extra expense and trouble of having an external sound box like the M-audio pre that many of us have. Of course, you still need some way to get the sample sounds (pink noise, sweeps, etc.) from the computer to the speakers... but if your receiver has USB input that'd work. Do current commercial receivers/prepros have USB inputs? I haven't kept up with what's out there now.
 
If used with a laptop, just use the stereo out headphone mini-jack (as suggested in their application notes.) Use a mini-jack to two female RCA cord, then connect standard RCA stereo cables to front input jacks that almost every receiver / pre/pro has.

Jeff

ps. This looks like exactly what I've been meaning to get for some time now. It comes with downloadable software that also looks like all that I'll need. Just ordered it. Thanks for posting this Pauly!
 
I'd worry a bit about the quality of the standard line out from a built-in jack... but I guess for the purposes of pink noise and such, it would be sufficient.
 
Max length of USB cable being just under 10', it may pose some difficulties for those with desktop PC. Just a thought. :think:
 
Why not just use an HDMI output from a laptop? That way you could actually input 7.1 audio.

John
 
Yeah it's a good thought. My older pre/pro (885) doesn't have a convenient front-side hdmi input, though. And not every laptop has hdmi out. Though I guess both are a lot more common these days, anyway.
 
I guess using the USB input bypasses the computer's typically "noisy" soundcard. Is it safe to assume that a measurment using a USB mic will be as/more accurate than using an outboard USB mic/pre?
 
I don't think it's any better - or worse - than using, say, the Behr ECM8000 with an outboard sound box like the M-Audio pre. It's just that with the USB mic, you don't need the outboard sound box at all, which saves you $80 or whatever if you're buying this equipment for the first time. All you need is the mic, and some way to get the sound from the computer to the receiver/pre-pro (the subject of the last few posts).
 
This is a HUGELY good product not because of any performance improvement but because it eliminates having to work with a sound card with Phantom Power (they tend to be bigger and more expensive), two cables (USB for the sound card and XLR for the mic), and calibrating the sound card to the mic (just annoying, though not hard). Indeed, this is a good tool at that price.
 
I finally got around to setting up this unit.

Just followed the online instructions and, except for a little pulling of hair and gnashing of teeth over having to register at Home Theater Shack in order to download a copy of REW, everything went smoothly.

I plugged the mic into my portable's USB port, and connected the portable to my main HT via the R/L audio inputs on the front panel using the headphone output jack (stereo mini-jack to RCA L/R - single cable that I had kicking around), and within a minute or so was running sweeps. While I've never used anything else like it, I can confirm Flint's post about this making a lot of sense and keeping things simple.

It will be a while, if ever, that I geek out and explore all of the possible information etc. provided by this combo, but for now I'm happy with what I saw. It confirmed what I've known all along: that in that room, with that combination of speakers and subs, using my chosen crossover points etc., I get pretty much flat frequency response throughout the bass region, and especially flat bass (+/- 2dB) from 10-40HZ, the range that my three "main" subs cover. I played around with crossover points (40, 60, 80, 100, 120, bypass) and confirmed that 40 Hz works best. I could have played around with each of the three subs - but saw no need to. (I'd previously used a Velodyne ICBM-1 to work all of that out.)

Note this is all about bass management of the mains - and excludes any effect / contribution from the big SVS which handles only LFE.

Jeff
 
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