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A winding road to a tasty signal chain


Amplifiers has been working on tracking at my place over the last few days, and last night we did some vocals. Ultimately, the signal chain was one I’ve wanted to try for a long time, but for various reasons I didn’t get around to really trying until now. The setup was:

Shure KSM-44 –>
Auditronics 110B Preamp & EQ –>
Universal Audio LA-3A (vintage) –>
Computer input (Layla 3G).

I really dug the sound. The LA-3A leveled Si’s more-dynamicker-than-average vocals nicely, and the bright KSM-44 was a perfect compliment to the smooth 110 pre.

The point of this post, however, is not the setup, though that’s nice: The point is how I got there, and the implications for the future of the setup.

When I first connected the LA-3A, I was getting signal into it and gain reduction out of it… and I could hear it working through the monitors. Sounded great. Problem is, no matter how hard I drove the comp, I didn’t see any gain reduction happening in the computer — it was nearly impossible to keep the level within the sweet range. After scratching my head for a while, I got out the Auditronics manual and traced the signal flow thorough those preamps. As it turns out, the issue was with the modification I had made to those preamp modules to make the echo send (Auditronics-speak for “aux send”) pre-fader, so that the fader didn’t affect the record level. Unfortunately, this mod had the side effect of making the record send pre-insert and pre-EQ, due to the routing on those modules. Unable to come up with an ideal fix, I ended up un-modifying one module (I just had to move a single jumper) and viola, a river max-o-squish flowed forth.

This all means that in order to track with EQ and insert FX, the mod will have to be un-done on all the modules, and thus the faders will affect the record send on every channel. Until now, the faders were primarily for the 2-track mixdown, control room, and studio send mixes, with the echo send knob being an independent level control going to the DAW, which worked beautifully. I haven’t come up with a way to get the mixer to do exactly what I want without many intense nights of soldering and PCB trace cutting, so for now un-modding the modules will probably have to suffice.

But the good news is: Some lovely vintage-gear-powered sounds have been made, and more are forthcoming.