Film-Tech Forum ARCHIVE: mic cable

This is topic mic cable in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Bas Haldermans (Member # 1521) on 02-12-2003, 04:58 PM:

I have to connect a mic to the cp650

What pins do i have to use of the connector to the cp 650.

Thanks bas

Posted by Michael Schaffer (Member # 1204) on 02-12-2003, 05:24 PM:

The installation manual is available for free download from this very website!

Posted by Paul Mayer (Member # 355) on 02-12-2003, 05:27 PM:

The info is on P.24 of the CP-650 installation manual on the Film-Tech site. Looks like standard XLR connector wiring--pin 1 is shield, pin 2 is hot (signal +), and pin 3 is signal -.

Posted by Jean-Michel Grin (Member # 1360) on 02-13-2003, 04:10 PM:

Don't forget to adjust the mic level on the front side trimpot !

Posted by Frank Angel (Member # 248) on 02-14-2003, 04:47 AM:

Paul,

Don't you mean 1 = shield, 2 = - signal and 3 = + signal? That's the way it is done in all of our studios. Isn't that the NAB standard?

Frank

Posted by Daryl C. W. O'Shea (Member # 1303) on 02-14-2003, 05:49 AM:

This is from a Crest Audio CA Series manual I had handy.

This is from the Dolby CP-650 installation manual.

Posted by Ray Derrick (Member # 1001) on 02-14-2003, 08:19 AM:

Frank

I think you will find that when Cannon 3 pin connectors (EP, XL etc) were first introduced (late 60's I think), the standard everyone opted for was pin 2 hot and pin 3 cold. Then at some point, some renegade US manufacturers decided to reverse pins 2 and 3 (Why? Just to be different I guess!) To this day, the majority of high end studio equipment manufacturers including top end mixing console manufactuers like Neve, Solid State Logic, Harrison and Soundcraft and ALL professional microphone manufacturers, still use pin 2 as hot. Having two conflicting common standards has been an absolute pain in the butt for every professional audio person around the world. Of course Dolby in their wisdom and to their credit, choose the only correct standard. If your studios use pin 3 as hot AND you use professional microphones like Neumann, AKG, Shure etc, then all your recordings are out of phase! Woops!

IMHO those idiots that chose to make pin 3 hot should be nailed up on wooden crosses all the way to Rome.

Posted by Scott Norwood (Member # 30) on 02-14-2003, 08:28 AM:

Otari tape recorders are wired pin-3 hot. If I recall correctly, Nagras are as well. A phase-flip cable or adapter is the cheap/easy fix (as opposed to rewiring the connectors).

Posted by Ray Derrick (Member # 1001) on 02-14-2003, 10:25 AM:

Scott it's been many years since I held a Nagra in my hot little hand but I seem to vaguely recall they also had reverse sex for the connectors (inputs male, outputs female). Is that correct or am I thinking of something else?

Posted by Steve Guttag (Member # 268) on 02-14-2003, 10:40 AM:

Anyone that wires XLRs as anything but pin-2 "hot" should be shot. One nice thing about Neutrik's "combo" jacks is that pin-2 is hot if tip is hot!

Then again, QSC went through a period where Tip was "-".

JBL for most of it's history has been postive on red mean inward cone movement...the exact opposite of the rest of the world.

Why does there always have to be someone that just has to be different!

Steve

Posted by Paul Mayer (Member # 355) on 02-14-2003, 12:00 PM:

I wondered how long it would take for someone to bring up the "XLR pin 2 hot vs. pin 3 hot" thing! [Big Grin]

All I know is that all of the theater stages, sound companies, AV companies, and TV production trucks that I work on in 'Vegas and SoCal use the "pin 2 hot" convention. I have heard of "pin 3 hot" but have never had to work with any sound gear actually configured that way. I must've lead a sheltered life.

Posted by Bas Haldermans (Member # 1521) on 02-14-2003, 02:39 PM:

Yes i understand the connection to a xlr connector. But how do i make the connection to the 9 pin connector (a female 'com' connector) to do b-chain.

Greetings bas

Posted by Steve Guttag (Member # 268) on 02-14-2003, 04:28 PM:

Make yourself a 9-pin D to XLR adapter cable...it isn't that hard.

Steve

Posted by Paul Mayer (Member # 355) on 02-14-2003, 04:40 PM:

From page B-5 of the CP-650 manual:

Front panel DB-9 connector pin assignments:

Pin 1 = + mic signal
Pin 2 = - mic signal
Pin 5 = Mic cable ground

NOTES: If using a cable made for use with the CP-500 add a jumper between pins 5 and 6.

Pins 1, 2 and 5 are paralleled with the XLR connector on the back panel. Don't have anything plugged into the XLR if you're using the DB-9 for EQing.

Posted by Ray Derrick (Member # 1001) on 02-14-2003, 06:13 PM:

Then of course, the importance of the absolute phase of a composite audio signal is somewhat academic, provided all channels in a multichannel system agree with each other etc.

There are some folk out there who claim to be able to hear the difference between an inverted audio signal and an uninverted one. But they fail to take into consideration the complexities of the audio chain, particularly in relation to the phase altering effects of filters and equalisers. For instance, most two-way speakers have the HF driver deliberately wired in reverse phase in order that the phase of HF and LF speakers agree with each other at the crossover frequency.

Posted by Scott Norwood (Member # 30) on 02-14-2003, 09:51 PM:

Ray--it's been a couple of years, but I believe that the 4.2 that I used had normal (female) XLR connectors, although that might have been a later modification by the rental house. Not sure about other Nagra products.

For those who haven't had the pleasure of working with them, Nagra tape recorders are works of art. Imagine a high-quality and indestructable tape recorder built like a fine Swiss watch and you have imagined a Nagra 4.2. Every other tape recorder--even professional Ampex and Studer models--feels like a cheap toy by comparison. Too bad that most Nagras don't take 10.5" reels. Pretty much all motion picture location recording was done on Nagras from the early '70s until the mid '90s, when portable DAT machines became popular. Nagras are still common, however and the company now also makes a line of digital recorders including the 4-track Nagra D format.

Posted by David Stambaugh (Member # 1102) on 02-14-2003, 09:58 PM:

Nagra is not exactly a household name. Just for grins I looked them up on the web -- the parent company is Kudelski Group. Say what? Whoever they are, they're into a lot of [Cool]

high-tech stuff.

Speaking of Nagra products as being "built like a fine Swiss watch", I just noticed Kudelski Group is headquartered in Switzerland.

Posted by Paul G. Thompson (Member # 655) on 02-14-2003, 10:00 PM:

Most of the XLR connectors I have to deal with in the broadcasting industry has pin "3" hot.