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Subject: RE: Normalling 1V/Oct inputs

From: "Dave Bradley" <daveb@...>
Date: 2000-02-22

Don't get Paul started on normalling - he's opposed to it on general
electrical principles. Others are opposed to it on philosophical grounds -
"don't normal cause you'll get lazy and quit experimenting".

However, I intend to do SOMETHING to mine because it's going to be a largish
system capable of 4 voice polyphony, and I don't want to use up the same
dozen patchcords every time just setting up kbd CV and gate signals. So
here's my two cents worth in a random stream of consciousness:

1. From an electrical standpoint, tis far better to normal both the hot and
ground wires from jack to jack instead of just normalling the hot wire and
depending on the ground back at the power supply to complete the circuit.

2. Tis better to normal with shielded wire than nonshielded. Practically, if
you combine this with (1) above, it should be equivalent electrically to
plugging in a patch cord.

2.5 You should only normal an input from 1 place, so you'll only have one
wire to deal with. Normal an output to several places, and all those ground
wires trying to connect to the same jack will get messy!

3. If you normal, tis better to figure out a way to be able to remove
modules from the cabinet without desoldering normalled connections. One
possible somewhat elegant but potentially expensive solution: mount a small
pcb behind the jack field on the module, and bring the connections to be
normalled up to some kind of alternate connector system. Not expensive and
bulky 1/4" jacks, but a pin and socket type deal. Need reliable connectors
for this. Emu did this with their system, but went with a hot wire only
system instead of carrying the ground.

4. When normalling inputs, always use the jack's normalling lug, NOT the hot
lug so that a jack applied to the front panel will override. When normalling
outputs, use the hot lug.

Aw, screw it. Here's an alternative: Under each row of modules, run a
Larry's Magic Buss(tm) strip. Divide it up into groups of 4 jacks such that
some groups are a simple mult, some output 4 gate signals from your
converter, some output 4 kbd CV signals from your convertor, etc. Wire this
all up such that the gate outputs happen to be just under your 800s, the kbd
CVs are available just under your 300s and 420s, etc. Now all you need is a
6" patchcord to run your common hookups, you don't have to unplug them, they
are out of the way, and you don't have the unsoldering/alternate connection
system hassles of true normalling when you remove modules.

Your approach sorta depends on the size of the system you are contemplating

Hey, I just realized I never answered your original question! To normal to
the 300's 1V/Oct input, disconnect the jumper from the normalling lug to
ground, and connect a shielded cable to the normalled lug and ground. Run
this to your converter. Any grounding issues should be no worse than if you
had plugged a cable into the front panel.


From: "Crawley, Eric" <esc@...>

Has anyone done any normalling of the 1V/Oct inputs on their MOTM 300s or
420s from the jack on the module? I was noticing that I was always using up
multiples for these inputs and I wondered if I could wire up a standard CV
source, such as a MIDI/CV output directly to the back of the jack.