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On this thread I will be posting a pictorial of ELCO/EDAC multipin connector assembly. Specifically a 90 pin female with fixed nut. I have been using multipin connectors extensively for a number of years now and recently I have been leaning towards ELCO/EDAC because of their flexibility of application, ease of use, sound electrical properties and price.

First step is to select the appropriate cable. The following application is for inside a preamplifier rack so a suitable STP (shielded twisted pair) cable will do.
I use exclusively AVP 5110-x cable for many reasons which I will go into on another topic perhaps.

Next the outer jacket is removed.

Then the insulation is stripped from the two conductors.

And the two inner conductors along with the drain wire are tinned.

The next step involves soldering the ELCO/EDAC pins to the wires.
Here is a closeup of the pin.

What makes the ELCO/EDAC connector an excellent choice for audio applications is their bifurcated pin design. Once mated these plated corrosion resistant pins create a low resistance positive electrical contact which is free from intermittance and virtually noiseless.

First I prepare the pins by laying them out on double sided Post-It tape.

I then solder a pin on each wire.

Note the section of 1/16th " clear heatshrink tubing over the drain wire. This is to avoid ground loops and more importantly, in mic level applications, these could be carrying 48VDC which you do not want shorting to anywhere!

Next I slip a piece of 1/8" heatshrink tubing over each of the two signal carrying pins. This is to prevent any cross conducting. I use tubing of two different colours to make identification easier when time comes to insert the pins into the connector body.

Here is a front view of the first twelve channels loaded.

And here is a rear view. Notice the 3/16" clear heatshrink tubing over each cable and onto the individual wires? This is to prevent any "migrating" of the wires.

Here is a shot before the 3/16" tubing got shrunk on the last twelve lines.

Here is the finished assembly.

Now I've attached a 2ELCO90 for theMiddle Atlantic Products UCP custom rack panel system. I used cap screws and threaded them into the plastic of the connector body from the rear as to not interfere with the mating of the female cable end connector.

Here is what the UCP panel looks like installed. Although it is not the specific one which will be housing this particular multipin connector. Notice the fourth panel over from the left is an 1ELCO90 housing a male panel mount which has a female cable mount mated to it.

Here is an unloaded female ELCO/EDAC connector with fixed nut, typically used as a chassis mounted connector.

Here is a female ELCO/EDAC 90 pin used as a cable mounted connector with actuating screw to assist in mating.

Here is the same connector with the backshell installed.

Here is a closeup of an ELCO/EDAC female 56 pin connector with actuating screw and backshell. This particular one is wired to the Alesis ADAT convention.

Here is a picture of the whole patch. You will notice that it has 8 ins and 8 outs.

Here is some miscellaneous patch using various ELCO/EDAC connector configurations.

The particular wiring convention that I use for my 90 pin connectors follow the AMEK standard. These connectors are used extensively on their large frame consoles. The following picture should explain why, it is a shot of the underside of my onboard patchbay.

The next picture that I have attached shows an error in wiring. If you look closely the shield and cold pins are reversed.