USB audio interface to use w/laptop for measuring room response?
- Thread starter MadFloyd
- Start date
Hi MadFloyd. Hope you are well and enjoying those amazing Magico speakers. Congrats again. The interface that I use for measurement is the Sound Devices USBpre-2. It serves as the mic pre-amp and interfaces to the computer via USB. Also, it can drive signal to your DAC via S/PDIF or Toslink so it pretty much does it all. I use Dirac Live imbedded in Amarra as the software measurement tool and create the room filter from the measurements. I have not used REW. DallasJustice has significant experience here and hopefully will add his thoughts. I followed his advice for my measurment set-up and it has worked out well.
Most simply buy a calibrated USB mic to use with REW. No separate audio interface required. Popular choices are Dayton Audio UMM-6 or the UMIK-1 (Cross Spectrum sells calibrated versions).
I was looking at buying the UMM-6 myself the other day http://cross-spectrum.com/measurement/calibrated_umm6.html - but before that, though, I downloaded REW and I can't tell you how much I hated its interface; I have not seen such a bad interface in ages.
You can play the tones through your system by connecting a second USB port or Toslink from your computer to your DAC and configuring your computer properly to use the DAC as the output device and the USB mic as the input device
I wouldn't use a USB mic like the UMIK. You would be better off with something that can send out the log sweep synchronous with the mic input.
Some of this depends on what you are looking for.
1. Cheap but flexible and good for REW and some 2CH DSP: TASCAM US-366
2. A little more accurate and even more flexibility: sound devices usb pre-2 is really great.
3. I want to get super serious about DSP and MCH setups and need really accurate measurements with REW and max flexibility: Lynx Hilo
There are 2 reasons why the USB mic isn't useful:
1. You can't calibrate it in REW. You have to just assume it's accurate. Maybe it is. I don't know.
2. If you ever want to demo any DSP software, it's much better to have a synchronous in/out. You can't do that with a USB mic.
1. Cheap but flexible and good for REW and some 2CH DSP: TASCAM US-366
2. A little more accurate and even more flexibility: sound devices usb pre-2 is really great.
3. I want to get super serious about DSP and MCH setups and need really accurate measurements with REW and max flexibility: Lynx Hilo
There are 2 reasons why the USB mic isn't useful:
1. You can't calibrate it in REW. You have to just assume it's accurate. Maybe it is. I don't know.
2. If you ever want to demo any DSP software, it's much better to have a synchronous in/out. You can't do that with a USB mic.
The Tascam works well with REW and with DSP software such as Acourate and Audiolens
As Don said and my link shows, these are calibrated mics, and the guy's reputation on calibrating THESE mics is beyond reproach. A calibrated USB mic should be enough, no need to go messing around with phantom power.
Regarding REW, its power and interface... Isn't XTZ an overall-better solution? We spend so much money on an inch of thin wire - aka fuse - so cost is not an issue here...
I'm not talking about mic calibration. I'm talking about the DAC/ADC's linearity. Normally you can compensate for a nonlinear ADC/DAC in REW by calibrating the device with a loopback.
http://www.roomeqwizard.com/wizardhelpv5/help_en-GB/html/calsoundcard.html
I also forgot to mention that the USB mics can't do absolute time measurement in REW. This could be useful for lining up speakers like subs with main speakers. The USB can't loopback for a time reference in REW. It's pretty useless, IMO. Especially since you could get a Tascam us-366 for $200 and a calibrated mic for $100.
Btw, it's very difficult to calibrate a mic down to 25hz. I used to have a cross spectrum mic. I now have an earthworks m23.
I also used to have the xtz. XTZ software is like a Cracker Jack toy compared with REW and REW is free!
http://www.roomeqwizard.com/wizardhelpv5/help_en-GB/html/calsoundcard.html
I also forgot to mention that the USB mics can't do absolute time measurement in REW. This could be useful for lining up speakers like subs with main speakers. The USB can't loopback for a time reference in REW. It's pretty useless, IMO. Especially since you could get a Tascam us-366 for $200 and a calibrated mic for $100.
Btw, it's very difficult to calibrate a mic down to 25hz. I used to have a cross spectrum mic. I now have an earthworks m23.
I also used to have the xtz. XTZ software is like a Cracker Jack toy compared with REW and REW is free!
Last edited:
Similar threads
 | Steve Williams Site Founder | Site Owner | Administrator |  | Ron Resnick Site Co-Owner | Administrator |  | Julian (The Fixer) Website Build | Marketing Managersing |