mics through patchbay question

What is three phase electrics? how do I wire a patchbay? ask all your techo questions here.

Moderator: Aaronw

bobmurphy
Posts: 42
Joined: Mon Oct 30, 2006 5:34 am
Location: Ireland
Contact:

mics through patchbay question

Post by bobmurphy »

hi - i have read on the forum that you can put mics through a patchbay but my behringer 1/4" patchbay says not to in the manual - what's the story - have i bought the wrong patchbay?

i have 12 lines coming from the liveroom into the 12 inputs in the control room but i wanted to be able to route a couple of them through the patchbay first so that i could plug in a mic or a di box in the control room. i was going to make up a couple of special xlr to trs mic leads that i could use to plug directly into the patchbay - is this normal practice ? - i used to work in a studio years ago and i think this is the way we did it.

edit: (another related question) i was also hoping to route the output from the headphone amp on a motu 8pre through the patchbay too - would this be ok to do ?
Aaronw
Moderator
Posts: 1771
Joined: Thu Sep 18, 2003 3:06 am
Location: Music City
Contact:

Post by Aaronw »

hi - i have read on the forum that you can put mics through a patchbay but my behringer 1/4" patchbay says not to in the manual - what's the story - have i bought the wrong patchbay?
Does it say not to run mics, or does it say not to run phantom power through the patchbay?
i have 12 lines coming from the liveroom into the 12 inputs in the control room but i wanted to be able to route a couple of them through the patchbay first so that i could plug in a mic or a di box in the control room. i was going to make up a couple of special xlr to trs mic leads that i could use to plug directly into the patchbay - is this normal practice ? - i used to work in a studio years ago and i think this is the way we did it.
What you might consider doing is making an XLR plate to plug your mics into. They can still come up to the patchbay at that point.
edit: (another related question) i was also hoping to route the output from the headphone amp on a motu 8pre through the patchbay too - would this be ok to do ?
If the signal is amplified, I wouldn't recommend it. If it's just a line level feeding to the headphone amps you'll be ok.
bobmurphy
Posts: 42
Joined: Mon Oct 30, 2006 5:34 am
Location: Ireland
Contact:

Post by bobmurphy »

it says:
Microphone inputs are for very low level signals and should
never be routed via a patchbay. Plus, the +48 Volt phantom power
from the mic input could damage other equipment. It is best to
plug mics directly into the mixer or via a wall box using good
quality balanced multi-core cables
i suppose ideally i would have a sort of Y arrangement going into the audio interface with 2 cables joining into one from both the control room and live room so that i could plug in a mic into the same input from either room as i needed but i suppose this would not be a good idea - or would it ?
Bob W.
Posts: 2
Joined: Wed May 23, 2007 3:13 am
Location: Los Angeles, CA USA

Post by Bob W. »

I have seen many installations that run mics through a patchbay, but there are some things to be aware of:

1. Mics put out a very low level signal, so
a. Do not run high levels on the same patch row
b. Use high quality connectors and patch cables

2. Mics require that the ground is carried through for shielding and as a common for the phantom power, so don't bus the grounds of your mic patch row to the gound of the rest of your system. Carry the grounds from your mic pre through the patchbay, and out to the mic panels, but keep them isolated from each other and the rest of the patchbay grounds.

3. It's always a little dicey to have 48 volts on your patchbay. Be careful!

My preference is to run the mics lines from the studio panels directly to the mic pre. I would stay away from any "Y" connectors on the mic pre. An unterminated branch hanging on a mic line can act as an antenna, and you could end up connecting two mics to one pre channel.
Bob Weitz
Post Reply