Mac and USB input devices

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Revision as of 15:03, 8 August 2017 by BillWharrie (talk | contribs) (more details regarding Audio MIDI Setup)
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Peter 09Jul16: Some (maybe all) of the images appear to be out of date for latest OS X, El Capitan. The meters are certainly old-fashioned non-default (small and not multi-colored. The "Sound" dialog at the top is not as it is in El Capitan.
  • Bill 07Aug2017: OK, I've updated this to Audacity 2.2.0 and Mac OS 10.11. Removed the ToDo.
On Mac OS X using current Audacity or legacy 1.3.12 or later, the following procedure should get sound from the USB audio input device into Audacity. This includes USB turntables, USB cassette decks and external USB audio input/output adapters.

1) Connect the USB device directly to a free USB port on your Mac. Do not connect through a USB hub. Turn the device on. If it is a USB turntable or cassette deck, begin playing an LP or cassette. For other USB interfaces, input some sound to the device.

2) Choose Apple Menu > System Preferences... then select the Sound preferences panel, then click on the Input tab.

Select USB Audio CODEC from the Input list.

Note that:

  • "The selected device has no input controls" - this means that whatever level the device sends to your Mac is what you get.
  • The grey "Input level" meter is showing that sound is being input.
Warning icon If there is no indication on the Input level meter, stop now and figure out why.
  • If the Mac is not recognising the USB Audio CODEC, try the steps in the green box "Detecting USB and Firewire devices" in this Frequently Asked Question.
  • You may need to use Audio MIDI Setup to configure the USB device before the Mac will recognize it. See the section below on using Audio MIDI Setup.

Assuming you have sound coming into your Mac through the USB device, continue as follows.

3) Start Audacity and choose Audacity > Preferences then the Devices section.

Under "Recording" make the choices shown.
Note that you do not want to set the Playback Device to your USB device in the case of a USB turntable or cassette deck. In most cases you will want the Playback Device set to "Built-in Audio" or "Built-in Output". This will cause playback to occur through your Mac's built-in speakers.
Click OK to accept the settings.

4) Click on the Transport > Transport Options menu and make sure that "Software Playthrough" is checked.

5) Note that the Input volume slider is greyed out and cannot be used. Remember that "The selected device has no input controls".


6) With the LP or cassette playing, or with sound being input to the USB interface, click on the recording meter to begin monitoring.

  • Make sure that the levels are below 0 dB, and that the red clip lights do not come on.
  • Some USB turntables have a volume control somewhere on the chassis. If the levels are too high in Audacity, look on the turntable or in your manual to see if you have a volume control. For external USB audio interfaces, simply turn down the volume of the device that is feeding the USB interface.
Warning icon If you got an indication on the grey System Preferences input level meter in step 2, but do not get any indication on the Audacity input level meter, go to the next section and use Audio MIDI Setup to set up your USB device.

7) If you have got this far and are getting a good indication on the recording level meters, you are ready to begin recording!

Using Audio MIDI Setup

There are reports that the above procedure will not work with certain USB devices, including some from Logitech. If you still can't get sound into Audacity, continue to set up the USB input device using the Audio MIDI Setup program.
You must use Audio MIDI Setup if you want to change the bit depth or sample rate of your device.

1) Quit Audacity if necessary.

2) In the Finder, choose Go > Utilities then open "Audio MIDI Setup".

If the "Audio Devices" window is not visible, choose Windows > Show Audio Devices

What the symbols mean
  • The input device with the microphone symbol is the chosen input device.
  • The output device with the speaker symbol is the chosen output device.
  • The output device with the Mac "face" symbol is the device that will play "alert" sounds.
Make the selections as shown above
  • Click on "USB Audio CODEC 2 in/ 0 out" to select it.
  • Click on the Action menu ("gear" icon) and select "Use this device for sound input".
Note that if you have successfully set the USB Audio Codec as the default input device in Sound preferences:
  • the microphone icon may already be beside "USB Audio CODEC 2 in/ 0 out"
  • "Use this device for sound input" may be greyed out in the Action menu.

Note that the microphone symbol has moved to the "USB Audio CODEC 2 in/ 0 out" device.

MacAudioMidiSetupUSB 2.png
Make the selections as shown above.
  • The Format settings of "44100.0 Hz" and "2ch-16bit Integer" are standard for most interfaces, and correspond to the audio CD standard.
  • Note that the "Volume" sliders are disabled - as expected, since the selected device has no input controls.

3) Quit Audio MIDI Setup, start Audacity and click on Audacity > Preferences then the Quality section:

Under "Sampling", set "Default Sample Rate" and "Default Sample Format" to match the settings you made in Audio MIDI Setup.

4) Test the input as in steps 6 and 7, above. If you still can't get sound into Audacity, post a message in the Mac section of the Audacity Forum.