Appendix B-If You Use An External Mixer

Appendix B-If You Use An External Mixer...

Our main objective is to get the signal we want to record to the Delta 1010LT, and to monitor the outputs from the Delta 1010LT. The 1010LT has a mixer contained on its chip that allows you to mix hardware inputs and software outputs and send it to an analog stereo output pair and/or the S/PDIF out. The 1010LT also allows you to record that mix into your music software as a hardware input. Still, some of you may choose to use a mixing console to achieve your multi-tracking goals.

A mixing console (sometimes referred to as mixing ‘board’ or ‘desk’) that is designed for multi-track recording has the ability to fulfill these two basic functions -- getting the signal to the recording device, and receiving the outputs of that recording device for mixing or monitoring. In this sense, a recording console is two mixers in one. A mixer designed for recording will also have the ability to send to one or more mixdown decks, to monitor these mixdown decks, to control separate control room and studio listening levels, as well as other recording-specific functions.

There are two basic layouts for the recording console, "split section" and "in-line." The split section design is arranged with a recording or ‘channel’ section (to send the signal to the recording device) side-by-side with a monitoring section (to receive the outputs of the recording device). The in-line design has the recording and monitoring sections "in line" within each channel module, so that each channel has two line inputs.

The recording section is distinguished by its bussing system, which takes the recording channel signal through a summing matrix to multiple outputs- usually in multiples of eight. It could be said that an ‘8-buss system’ is designed for 8 track recording, and a 24-buss system for 24 track recording, etc., but this is not written in stone.

What we are describing here is the extreme- a professional, costly piece of gear that has been purchased for this one specialized purpose. There are features inherent in other types of consoles, however, that will allow us to perform these two separate functions of recording and monitoring. A sound reinforcement or a broadcast console, and in some cases a recording console, might offer a bussing system in the form of "sub-mix outs." These are usually arranged in stereo pairs with a set of level control faders for each pair. This configuration can be effectively used for recording, as long as the record channels are taken out of the stereo buss. The difference here is that there is no real distinction between the recording and monitoring sections.

Some line mixers have a number of effect or auxiliary sends for each channel. These sends will have their own individual level control and will receive the signal either pre fader or post fader, i.e. either independent or dependent on that channel’s fader level. It is possible to use these "aux sends" to send a signal to the recording device. A pre fader send is certainly preferable, since this will allow for a recording level that is separate from the monitoring level.

The bottom line here is that you can not use the ‘main output’ of your mixer to send a signal to the recording device, and then take the outputs of that recording device back into the mixer (whose signal also goes to the main out). This creates a feedback loop, bad for your eardrums and bad for your equipment.

One modern console design gets around that by offering an "alt out," which is an alternate