Device Toolbar

Device Toolbar  provides an easy way to select the combination of interface host and sound device to be used for playback and recording, without having to open the Devices Preferences. This toolbar may be resized with the drag handle.

Device Toolbar grays out when playing, recording or paused. You cannot change device choices while the device is in use.

Audio Host

Selects the particular interface with which Audacity communicates with your chosen playback and recording devices. On Windows the choice is between MME (default) or Windows DirectSound and on Linux, between ALSA (default) or OSS (where your Linux distribution supports OSS). On OS X, Core Audio is used. Generally you will want to use the default. On Windows XP or earlier and given a recent computer, DirectSound should produce lower latency.

Peter 24Apr11: is choosing the default MME host for any Windows machine really the preferred choice? I thought that MME was the older host that Microsoft provides - and that usually the more modern Windows DirectSound is to be preferred on Windows platforms.

• Gale: I still feel MME is the safer default for older, slower machines. It's possible to give more detail but I don't think the Manual is the place because of the complexity. Do lots of people ask? I am not aware of that, but if so, we could have a FAQ.

Output Device

Choose the device in or attached to your computer that you want to use for playback.

Input Device

Choose the device in or attached to your computer that you want to use for recording. Input sources are no longer chosen in Mixer Toolbar.

In most cases (for example, the inbuilt computer sound device), each entry for input device consists of the input type (such as microphone), followed by the name of the audio device the input belongs to. If a device only has one possible input for selection by the computer (for example, a USB microphone), only the name of the device will be listed, with no input type.

If you attach or disconnect an external device while Audacity is open, use Transport > Rescan Audio Devices to update the device lists before playing or recording.

Input Channels

1 (Mono), 2 (Stereo) or the number of channels that are provided by the drivers of your sound device. On most inbuilt sound devices, especially on Windows, only mono or stereo will be available. For some devices on Windows, choosing Windows DirectSound in "Host" above may be more likely to reveal options for recording more than two channels. On some devices capable of recording more than two channels, an explicit "multi" device may appear in the "Device" drop-down for recording all the channels simultaneously.

• If your input is mono, such as most microphone ports for the inbuilt sound device, selecting "2 (Stereo)" in Input Channels duplicates the mono source to both channels, merely producing a dual mono recording.
• If your input is stereo, then as well as setting Input Channels to "2 (Stereo)", ensure any settings in the system or sound device control panels are stereo. Many input devices on Windows Vista and 7 default to mono recording even if they are stereo devices. To correct this, follow these instructions.