Pops and clicks

[joelange]

Hi,
I am getting really scratcy pops and clicks on playback for any signal through REW. Whether it be pink noise or sweeps. I've tried the Java driver and using ASIO with my UAD apollo 4x (which definitely doesn't pop and click while i'm recording), but i can't get a clean signal from REW to come through. What am I doing wrong here?

 

[John Mulcahy]

For ASIO make sure the buffer size isn't too small/latency set too low. For Java drivers it suggests something is pushing REW into the background long enough to let the audio pipeline run out of data. There was some discussion of similar issues on this DIY Audio thread, there is a potential workaround by increasing the priority at which REW runs in post #734.

 

[joelange]

I will give that a try, but it's a very high end audio interface, with extremely low latency.

 

[joelange]

okay, tried that. Kicked the buffer size up to the max 2048, and no improvement. I am using the ASIO4All driver because i couldn't get it to work using the UAD ASIO driver directly, and I read on here that the ASIO driver only works with ASIO4All. I do have the miniDSP device in line to the monitors, but it is playing fine through it from my DAW so i don't think it's that.

 

[John Mulcahy]

Native ASIO drivers usually work OK (Steinberg and RME drivers certainly) but there does seem to be some issue with the UAD driver. ASIO4All is really only for devices that don't have their own drivers or when trying to combine multiple devices into a single pseudo-device in an ASIO wrapper. If you use ASIO4All make sure you only enable the inputs and outputs of your interface and not any other devices. FlexASIO is an alternative wrapper.

 

[joelange]

yeah, i tried everything and i flat out can't get it working with my Apollo. I'm thinking of just using the onboard sound card (rerouting it to my monitors and using a DI for my CM8000 on the input). Do you think that would work?

 

[John Mulcahy]

Yes, don't need anything spectacular for making measurements.

 

[joelange]

Here's a question. Can I export pink noise from REW, then record it with my cm8000 onto a channel in my DAW, then import those recordings into REW to analyze and create an average analysis? I'm trying to flatten out my monitors in my room with MiniDSP.

 

[John Mulcahy]

Yes, though you could do the same with measurement sweeps. If you want to use noise save Pink periodic noise and make sure the sequence length is the same as the FFT length in the RTA. The captured WAV file can be dragged onto the RTA window or opened using the WAV button. When analysing periodic noise signals the RTA window should be set to Rectangular, here are example settings for a 64k FFT:

 

[joelange]

I was able to do it using my onboard sound card. thank you.