INTERACT FORUM

More => Old Versions => JRiver Media Center 20 for Windows => Topic started by: Primare Knob on January 03, 2015, 06:40:30 pm

Title: Using MC20 WDM driver for acoustic measurments with REW
Post by: Primare Knob on January 03, 2015, 06:40:30 pm
I think the answer is yes to the posted question, but can I set it up with Timing Reference as wel when using USB audio devices.

At the moment I am using an USB mic and DAC with REW, but due to the lack of a physical audio card I am looking for a way to do the physical hardware loop inside software.
Timing Reference in REW requires a physical loopback for measuring hardware latency, if I understand it correctly.
Title: Re: Using MC20 WDM driver for acoustic measurments with REW
Post by: mattkhan on January 04, 2015, 03:19:34 am
Strictly speaking rew does not need a physical loopback, it just needs a copy of the output signal (with the same sort of impulse peak, eg not put through a low pass filter) to arrive on the specified input device. It doesn't even need 2 output signals.

The way I do this is via the mixer app for my rme fireface using its loopback capability. This is perfectly reliable as it is all the same device/driver stack. Whether you can get useful data out of this approach when going through multiple drivers/apps seems unlikely.
Title: Re: Using MC20 WDM driver for acoustic measurments with REW
Post by: Primare Knob on January 04, 2015, 04:54:11 am
I am sorry, but I having a hard time following this. I am a newby with this kind of stuff.

What I would like to get is a reliable measurment of my speaker with as little room reflections as possible by using gating/windowing.
Title: Re: Using MC20 WDM driver for acoustic measurments with REW
Post by: mattkhan on January 04, 2015, 05:01:55 am
I am sorry, but I having a hard time following this. I am a newby with this kind of stuff.

What I would like to get is a reliable measurment of my speaker with as little room reflections as possible by using gating/windowing.
you only need a loopback if you want to to accurately sum multiple responses, do you need to do this?