Crackle in bass when recording from USB mixer [SOLVED]

Split from https://forum.audacityteam.org/t/crackle-recording-from-usb-tape-player-solved/33389/1

Hi, I am having a similar problem. I have version 2.0.5 and am recording through a decent USB mixer. The playback sounds OK until the bass kicks in and it crackles on any of the bass tones and kick drum. If I kill the bass on the mixer when recording then the crackle disappears on playback. I have lowered the mic input volume to 0.05 and reduced the output volume to 20% on my mixer and still the problem occurs. I have also re-installed the software on to another laptop (both are windows 8) and the same issue is still there. Any help would be much appreciated as its driving me crazy…!

Set your recording levels so that the blue recorded waveform is about half the track height. The waveform should never touch the top or bottom of the track.

Hi,

Thanks for your response.

The blue waveform is probably sitting at about 10-15% of maximum, given my seriously low mic and input volume, if it was any lower it would disappear - still not sure what to do.

Cheers,

Christian

Where are you listening to the playback?

Gale

I am playing back within audacity on my laptop - I have tried on two different laptops and have the same issue

decent USB mixer.

Make and Model Numbers are good.

Bass is pretty classic for creating overload distortion. The blue waves are huge, usually the largest, most powerful waveform in the system. Now we get to figure out where it’s getting killed.

After you tell us all about the mixer, how are you getting the bass (and drums) into it? If microphone, which one down to model numbers.

Koz

Through the laptop’s built in speakers?
You can’t expect to get bass reproduced properly through laptop speakers.

We can also take from the other direction. Export part of the bass distortion as very high quality MP3, and post it on the forum.

https://forum.audacityteam.org/t/how-to-post-an-audio-sample/29851/1

You should be able to get in five or six seconds before the system cuts you off.

Laptop speakers and earbuds are trash for listening to good quality music.

Overloaded blue waves either go all the way up and down on the timeline, or have very odd looking flat tops and bottoms.

Koz


Hi, thanks for the replies. I have listened through my laptop by plugging in my headphone through the jack, so its not coming through the speakers. For clarity, I am using audacity to mix house music from MP3 and WAV files using Pioneers CDJ 850’s and a Behringer 900 USB mixer - I have uploaded a snippet of what I am experiencing as an MP3 along with a screen shot of the waveform using PDF. Thanks in advance for any help or advice

You are heavily overloading something somewhere, even though the final recorded level is very low.
You will need to describe, in detail, the exact “signal path”. Where each and every sound originates and the path it/they take to reach Audacity.

Ok thanks Steve. The CDJ’s are running through the mixer and the mixer is plugged direct into my laptop through the USB. Nothing is being fed from my amplifier. I have also reduced the bass on the eq on the mixer, so that it sounds greatly reduced on my monitor speakers. The only way for me to stop it completely is to totally kill the bass on the mixer. I have switched to different USB ports, switched cables just in case, but still the same.

Plug your headphones into the mixer and listen to the mix with the bass turned up to a reasonable level.
Do you hear any distortion (crackle)?
How high is the level on the Behringer 900 meters?

There isn’t any distortion through the headphones through the mixer, or from the monitor speakers. I have set the bass to -4 on the clip i have uploaded and the mixer has a ±6 range - the mixer is only about 2 months old as are the CDJ’s

I’m referring to the LED “Level Meter”. How high is that going (maximum peak level) while you play the mix?

FIXED…!! I have just recreated the mix and it was just nudging into the red which is zero on the meter which runs from -30 to + 7- I have turned the gain down a touch and returned all other volumes to their normal levels, including the mic input on audacity and this has cured the problem.
Thanks for your help…!