Your computer’s built-in sound card probably sounds OK for playback of downloaded music. But the record function is much less than professional quality. Fortunately, it’s not difficult to add pro-quality recording and playback to your computer. A USB connection is one popular method.

If you already own an audio mixer, simply add a 2-channel USB interface between the mixer and the computer. The mixed stereo output of the mixer will be sent to the computer to be recorded, and playback from the computer can be directed to an available input channel on the mixer.

Several mixers have the USB interface built right inside. Less clutter on the desktop. Nice.

The earliest USB, version 1.1, is limited to 2 channels (stereo record, stereo playback). Connecting to the computer is pretty simple… just plug in the USB connector, and the computer will configure itself automatically. No drivers to install.

The newer USB 2.0 offers more capabilities, but may not work with some internet
streaming services. Let me explain:

Every USB2.0 mixer I have seen plays 2 tracks (stereo) from the computer, the same as the older USB1.1. The recording operation, however, is a bit different…

A small 8-channel mixer may send 10 separate audio channels through the USB cable to the computer. (Larger mixers will send more channels.) In addition, the mixed stereo output will also be sent on its own pair of channels.

Like this:
Mic 1-4 = USB channels 1, 2, 3, 4
Stereo 5/6 and 7/8 = USB channels 5, 6, 7, 8
Main Stereo Mix = USB channels 9, 10

So, your recording software would capture a 10-channel recording, which can be re-mixed later. This makes it convenient to clean up any imperfections that may have existed in the original “live” performance. The first 8 channels of the recording represent the 8 input signals, and the original live mix is on channels 9 and 10.

Some internet streaming services can only work with USB channels 1 and 2. This is fine for a USB1.1 system, because 1 and 2 is all there is. But on a USB2.0 system, channels 1 and 2 only contain sound from the first 2 microphones, not the complete mix. The mixed channels are down on tracks 9 and 10, which the streaming service can’t use.

If you pre-record your program, there is no problem. When you produce the final mix-down, it will be a 2-channel recording that will play out normally. If, however, you perform your program “live” to the internet, this condition may come up. The easiest way to deal with this is to use a mixer that operates with USB1.1… the 2-channel only version.

Check your streaming service’s capabilities first, then decide which method is best for you.

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