Measurement may be Corrupted

[matthew.facca]

Hey all,

I'm getting the following error whenever I make a measurement, regardless of whether it's through the microphone or loopback to create a calibration file. I also see some significant HF ringing on each measurement, the frequency of which will vary on each measurement. I've seen it as 2kHz and as high as 10kHz.

Here are screenshots of my preferences, the preference page while setting the input level for loopback, the error message and an attempt at measuring the interface's frequency response. I'm using a UA Apollo and have made sure that no signals are being re-amplified through the UA Console app.

Any ideas on what I'm missing here?

Thanks in advance.

 

[sam_adams]

First, update to the latest release candidate, 5.20RC5. Make sure the sample rate for the device in Audio MIDI Setp.app matches the sample rate in REW. Make sure that you don't have any odd routing setup in the device for the loopback, like monitoring, turned on. Try using a cable loopback for the reference signal.

 

[John Mulcahy]

A trace like that would typically be due to the capture being truncated due to high latency, so the end of the sweep is missed. Reducing the buffer size settings on the soundcard preferences may help, in addition to Sam's suggestion of making sure the sample rates for the input and output in Audio Midi Setup match the rate selected in REW.

 

[matthew.facca]

Reducing the buffer size to 16k on the input and output did it. Thanks!