I’m using a Numark Stereo iO audio interface to convert some vinyl to digital. Its a phono turntable connected directly to the USB interface then to my computer. I am happy with the recorded sound but I’d like to tweak the input levels of the recording every so slightly in order to avoid clipping and depending on the sounds levels of the actual vinyl. The hardware has no volume/gain so I need do it via the software but I can’t figure out how to do it Audacity.
You cannot on Mac. Apple don’t normally allow USB input devices to have a system input control, so there is no slider for Audacity to control. You can look in Apple System Preferences: Sound but it will probably say “The selected device has no input controls”.
If the input is clipped, a software control would only make the clipping quieter, not prevent it.
The Numark interface seems to have RCA outs you can get an adaptor to connect those to the Mac audio in, then you can control the input level coming into Audacity both through the volume control on the interface and the system/Audacity slider for audio in.
I’m trying to adjust the recording input levels within Audacity 2.03 downloaded off the zip file on OS X 10.6.8 with a Sony PS-LX300USB turntable. The input slider in the mixer toolbar is greyed out though and I can’t seem to find a way of adjusting within Audio Midi Setup. From the comments I’ve read here, it looks like this is something I am not going to be able to change? Could you please confirm. I’ve got output through the computer speakers ok.