Technical blog and writings by Micah Webner.

Using Matrix Outputs for Recording and Other Distribution

When we first moved into our current sanctuary in 2001, we set up a wild assortment of connections to feed cassette and CD recording, FM hearing assist, the 70V system for the cry room, and so on. This short-lived arrangement became very cumbersome until we found a good solution that included sensible use of the matrix outputs on our Allen & Heath GL4000 console and the addition of a Rane SM 26B splitter mixer.

Although our main speaker system is mono, we mix live music in stereo, which gets panned between our Matrix C and D outputs. Those, in turn, go into the dbx® 266xl compressor that was delivered with the system. The compressor channels are stereo-linked to keep things balanced.

The compressor outputs are fed to the Rane splitter, which in turn feeds stereo or mono mixes to a variety of outputs. This mixer is one of the best pieces of gear I've ever used, despite the fact that we purchased it used, and the volume pot on channel 5 is bad. (It only works when turned all the way up.) That one flaw explains how the rest of the system was tuned.

To tune the system I set levels until the FM Hearing Assist was on the verge of shredding the ear piece when the receiver is turned all the way up. From that setting, I set the tape outputs to where the cassette recording levels were peaking just a hair above 0dB. Next I set levels for CD recording and all of the other outputs. When the operator adjusts the tape record levels using the output gain on the compressor, everything else stays at about the right level, too. Generally, it's at 0dB for music and around +10dB for speaking. We did have to tweak until levels were consistently right for all systems, but now it is very easy to manage all of these different outputs with one control.