What is the function of the Mix knob on my Fast Track USB/Podcast Factory USB/ Fast Track Pro?

The Mix knob on these devices controls the audio mix sent to select analog outputs, fading between the input signals from microphones, guitars, or other audio sources plugged into the device and the output signal from your audio application software. When turned fully counter-clockwise (input position), only the input signals from external sources are heard at the affected outputs of your device. When turned fully clockwise (playback position), only the output signal from your DAW software is heard at the device’s affected outputs.

Next to the Mix knob you will find a “stereo/mono” input selection button. If you are monitoring a mono input source (such as a guitar or microphone plugged directly into one input on your Fasttrack) you will need to have this button set to “mono” so that the mono input signal is panned to both your left and right speaker or headphone ear.

The outputs associated with the Mix knob are generally those that would be used to connect to a monitoring system like speakers or headphones. On the Fast Track USB and Podcast Factory USB, the outputs affected by the Mix knob are the red and white “1/L” and “2/R” outputs and the headphone output. On the Fast Track Pro, TRS outputs 1 and 2 (along with RCA/phono outputs 1 and 2) are affected by the Mix knob.

The advantage of having this type of Mix control is that you can create your own monitoring mix between the external input being sent to your computer and the software output coming back from your computer’s recording/DAW software.

For example, if you were recording a live instrument track, and wanted to be able to hear other pre-recorded tracks in your project while you performed, you could set the mix knob halfway between Input and Playback. Setting the Mix knob halfway between Input and Playback would allow you to hear your instrument input (with zero latency) while recording, while allowing you to also listening to the other tracks playing back from your DAW at the same time. In many cases, “directly monitoring” your external input like this is preferable to relying on the signal coming back from your DAW software to provide you with live input monitoring, as the slight delay introduced by having to send the external input signal from your instrument to your computer/DAW then back to your audio interface can make it difficult to perform your music reliably.

Lowering your latency/buffer settings for your hardware (when possible) can reduce the amount of delay inherent in monitoring your live input through your software, but the zero-latency monitoring offered via the Mix knob will always allow you to accurately and comfortably monitor your performance regardless of your hardware latency settings.

The Mix knob does not affect the signal being sent to your computer for recording in any way.

Knowledge Base