Cant control input level - Turntable w/Mac

Hi, I’ve tried a plethora of things with no avail. Used lots of Google and read many topics here. I did find a few similar posts. I’m using a 2022 Macbook Air M1, MacOS 13.2.1 and tried the 3.3 beta as well as 3.25. The only way to get the slider for input to move is to pause recording double click and change value. It has no effect on levels. It also often reverts to the default and then can not be accessed again. I also tried to makes changes through the Mac Sound Control Panel and Audio Midi Setup App. No luck with either. It’s probably simple ,but it’s escaping a solid effort… Thanks in advance.

I’m a Windows guy, but…

Are you using a USB audio interface or a USB turntable? Often you can’t adjust the digital recoding level with USB input. You need to adjust/control the analog level before it’s digitized.

If the level is low you can use the Amplify effect after recording.

If the signal is too hot and you are clipping/distorting the analog-to-digital converter, you need to lower the analog level before it’s digitized.

That’s an indication that the input level cannot be adjusted, as DVDdoug describes. This is common with USB input devices on Mac (the exception being some USB microphones).

It’s a turntable with USB out.

Bummer. Peak levels go to about 0 db, well above the recommended -6. That said I don’t hear any clipping. Maybe I should just ignore and digitize away?

No idea how to lower analog level…


Many USB turntables have a “hidden” output volume control. Check the manual.

Thanks again, no visible nor hidden output volume control.

As long as I don’t hear any clipping, I guess I should just get on with it and digitize away?

Record an album, then check the recording with View (menu) > Show Clipping. Don’t worry about ticks and pops showing as clipped.

What is the make and model of the turntable?

Lots of clipping just within the first 30 seconds of the first track.

It’s a very nice turntable (I borrowed); Audio-Technica, Direct Drive Professional Turntable, AT-LP120-USB.

The manual states that the “Phono/Line” switch on the back has no effect on the USB output level, but let’s try recordings at each setting anyway.

There is almost no info on the web about this turntable being too loud. If you have a lot of LPs to digitize, look into the Behringer UFO-202. This is an analog-to-USB interface with a built-in phono pre-amp. Use it with the turntable output switch set to "Phono. It’s what I used to digitize my vinyl collection.

If you find that the UFO-202 is hard to get (at a reasonable price) you could instead try the UCA-202, which you would use with the turntable output switch set to “Line”.

Thanks. Will give this a try.

Any idea if running under Windows via Parallels could be a work around?

Is it a bug (or missing feature) in Audacity that prevents this adjustment?

Nothing bad happens when you get close to 0dB but the analog-to-digital converter can’t go over 0dB. The -6dB recommendation is avoid clipping on unexpected peaks.

You can also go quite a bit lower (and Amplify later). …If you remember analog tape, you wanted a “hot” signal to overcome tape-noise, and tape is more forgiving if you go over 0dB. It can go over 0dB and then it starts to soft-clip. But with digital there is no tape noise!

That’s an option. Analog records are “imperfect” anyway and although you can always hear background noise you may not hear slight clipping.

It probably won’t happen with every record, but on the other hand some records may be worse.

It also doesn’t have a recording-level control although reports of clipping are also rare.

That won’t help. The analog-to-digital converter inside the turntable (or inside the interface) is clipping. When that happens you can’t fix it on the digital-side.

I recently bought an ART USB Phono Plus ($100 USD) when I had trouble with my old setup, although I haven’t used it yet because I found a digital copy of the album I wanted to digitize.

It has a recording level control and switchable line/phono inputs.

I got an external RCA to USB D to A and despite it also having absolutely no way to adjust output level, it’s default is lower and close to ideal, so I’m finally off and running.

Interestingly, this device exhibited a functional level output slider in Audio MIDI setup, but adjustments had zero effect on levels…


That’s actually good because otherwise you could be clipping the ADC and Audacity wouldn’t show red and you’d never know (unless the distortion is bad-enough to be audible, or unless you zoom-in and look at the peaks).

Thanks everyone for all the help and tips!

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