My go with REW, getting popping noises on audio out

[wheezil]

I want to use REW to measure room response for a performance space.

I've got a UMIK-1 and hooked it up to my laptop, which has a Realtek headphone output going to an AVR. This isn't what I'll be using for the real show, but I wanted to test it at home. Audio from music sounds just fine, but when I run the REW sweep the sound has a lot of popping and REW complains of noise or distortion. Any idea what is going on? Is this even going to work with the dumb built-in Realtek output? I seems like REW is *measuring* just fine. Somehow the generated sweep signal is getting botched. I've tried adjusting sound levels, even switched to headphones and it is the same. Any suggestions?

 

[wheezil]

Doh! I have to calibrate the sound card first!

 

[John Mulcahy]

If you are using the Java drivers pick the output device whose name starts with EXCL to ensure WASAPI Exclusive drivers are used. That allows REW to force the device sample rate to the rate chosen in REW, otherwise the OS will resample between rates. If you are using some ASIO wrapper consider reverting to the Java EXCL, for ASIO buffer size should be set to a large value.

 

[MavG19]

Hi all, first post. I'm having the same issue using a Win 10 Pro PC and MiniDSP mic. I tried calibrating the sound card using the EXCL option and I cannot get the input anywhere near the default output set at -12 even with trhe PC at 100% and the amp cranked - getting dangerous at this point. (to my ears and speakers). What am I doing wrong?

Thank you, IM

 

[John Mulcahy]

There is no soundcard calibration with a USB mic, as the help says.

 

[MavG19]

I've read the help files, set the PC card to 16 bit and determined that the popping/distortion is only present when the MINIDSP USB mic is plugged in. I've adjusted every setting I can find and I am not sure what else to check.

 

[John Mulcahy]

set the PC card to 16 bit

Meaning what? And why?

Please attach a screenshot of the REW soundcard preferences.

 

[MavG19]

Thanks for the assist. The help files said to set to 16 rather than 24 bit. I did install Realtek ASIO drivers but dont know which input / output to pick (1 or 2) - both screen shots attached. Thanks again.

 

[John Mulcahy]

The help files said to set to 16 rather than 24 bit

That's a misunderstanding. The base Java drivers only deliver 16-bit data, the EXCL device entries deliver the full capability of the device. Neither require changing the device bit depth.

You can't use a native ASIO driver because ASIO requires input and output to be on the same device. Your Java settings look fine.

Popping is typically caused by another process taking up so much CPU time that REW is shut out long enough for data to be lost. That wouldn't be affected by whether or not the mic was connected though. Latencymon can show you whether that's an issue.

 

[MavG19]

I installed it, shut down all unnecessary processes and ran latencymon and the conclusion/report is my system is suitable for real-time audio. Sweep tone is still full of static/popping noises.

 

[MavG19]

I installed it, shut down all unnecessary processes and ran latencymon and the conclusion/report is my system is suitable for real-time audio. Sweep tone is still full of static/popping noises.

Actually when I checked again after opening a browser to post this note, latencymon reports I do have issues so perhaps when REW is running the performance isn't adequate. I've adjusted the power settings that latencymon suggested so maybe my PC just isn't up to the task.

 

[MavG19]

Problem solved. Used my wife's laptop.

Both are HPs, mine is higher spec so no clue why.