Recording Preferences

Accessed by: Edit > Preferences > Recording    (on a Mac Audacity > Preferences > Recording)

Click on any of the other Preferences sections in the above image to go directly to that Preferences page.

Playthrough

Peter 10Oct13: The advice here conflicts somewhat with How to set up Audacity where Bill wrote back on 02Apr11: "Hardware playthrough does not work on Mac, ever.". If the information here is deemed to be correct then I propose to replace the information on How to set up Audacity with the material here on Hardware Playthrough and Software Playthrough as the information there looks seriously misleading possibly to the point of being wrong. If Bill's earlier comment re. Hardware Playthrough on Mac is still correct then we need to modify this page.

• Gale 11Oct13: You can take it that Hardware Playthrough will not work on most Mac hardware.
• Bill 10Oct13: I know of no Mac running OS X that can do hardware playthrough using the built-in audio hardware. External hardware (such at the UCA-202) may have its own "hardware playthrough" with near-zero latency, but that has nothing to do with Audacity or OS X. Audacity on Mac does not have the "Hardware Playthough" menu item in the Transport menu (a good start). If this Prefs option is meant for Mac only it should be removed IMO. In the mean time we must document it. I just think it's silly to keep it around when it (almost?) never works. Naive Mac users may try turning it on then be disappointed when it does nothing.
  • Peter 12Oct13: In the light of Bill's feedback should we consider entering this hardware playthrough behavior as a bug on Bugzilla, with the suggested resolution of removing the functionality as Bill indicates? That way some focus would be on this issue with a chance of getting it fixed for 2.0.6.
  • Gale 12Oct13: And as I keep asking, why do we get no user complaints that it doesn't work, and why do Apple not remove "Thru" from Audio MIDI Setup? I don't think it's a bugzilla entry but a -quality list discussion (after doing some research on it and after 2.0.5 release).

Peter 20Nov13: ToDo-2 Please review. I no longer think there is conflict with what is here and what is on How to set up Audacity - I have strengthened the advice re h/w playthrough seldom working on Macs by using an alert and added a link for the reader to get more information.

• Overdub: Play other tracks while recording new one: Makes existing tracks in the project play when you click the Record button in Transport Toolbar. You can decide which tracks will play according to their mute/solo buttons. When Overdub is enabled, recording will stop when the recording cursor reaches the end of a selection region. Turn overdub off if you want to record past the end of the selection.
• (Mac only) Hardware Playthrough: Listen while recording or monitoring new track: Allows you to hear the input by sending it directly to the output of the same audio device you are recording from. This incurs no latency or CPU usage.

Unfortunately Macs have not had proper hardware playthrough support for some years. On most machines Audacity's Hardware Playthrough is not functional.

Windows and Linux  users may be able to enable hardware playthrough on some machines by going to the operating system's mixer, then in the playback side, unmute and turn up the level of the input being used. See How to set up Audacity for more details.

• Software Playthrough: Listen while recording or monitoring new track: Allows you to hear the input by sending it to any chosen playback device. This permits the recording and playback device to be different. Expect some latency in the sound that you hear, due to the time taken for the computer to process the audio. This option may cause recording dropouts on older, slower computers.

Software Playthrough must not be used for recording computer playback because it will create feedback echoes.

Useful Tips:

• If you enable monitoring with either hardware or software playthrough, you can listen to the input without recording it.
• For some examples of setting up equipment to record without playthrough latency, see this Tutorial about Recording overdubs.
• When recording from a microphone, listen in headphones so that the microphone hears only what you are actually recording.

Latency

• Audio to buffer: A "buffer" is a chunk of audio waiting for the computer to process it. At the default 100 milliseconds (ms) setting, the audio will take 0.1 seconds to travel through the sound card when recording or playing. Decreasing this value means recordings will be laid down on disk with less latency, and playback may respond faster. However, the computer will have to work faster so that it's ready to process the shorter chunks as soon as required. Setting this value too low (for example to 1 ms) will mean the computer will not be able to keep up, and neither recording or playback will work. 100 ms is a safe setting for most computers.
• Latency correction: On most consumer systems there will be a delay between singing or hitting your note and it being laid down in the recording. When the default Overdub setting is enabled, Audacity will push recorded tracks backwards by 130 ms to compensate for this delay. If your latency is constant, you can adjust this correction value so that your recorded tracks should end up properly synchronized with the other tracks after correction. To set a custom latency value for your system, see the Latency Test page.

Sound Activated Recording

• Sound Activated Recording: Enables or disables Sound Activated Recording. When enabled, click the Record button in Transport Toolbar to start the Sound Activated Recording session. Recording will now occur whenever the received input is above the Sound Activation Level you specify (see the item below). Recording will pause whenever the received input falls below that level. Press the Stop button to stop the recording session.

You cannot pause Sound Activated recordings manually using the Pause button or corresponding menu item or shortcut.

• Sound Activation Level (dB): Sets the threshold level in dB which triggers Sound Activated Recording. The range of the scale is determined by the Meter / Waveform dB range currently set in Interface Preferences. Although dB are logarithmic units, the actual scale values are displayed linearly (equally spaced for each value). The currently set dB value is displayed dynamically above the center of the scale.

For easier access, Overdub, Software Playthrough and Sound Activated Recording can be toggled on and off by using their respective entries in Transport Menu, or use Keyboard Preferences to allocate a keyboard shortcut to them.