Patching delimas - Patchbays

Submitted by Sidhu on Wed, 01/03/2007 - 09:26

Hello!

I will be repatching my small studio this week. To include a following :

16 Mic inputs to the control room.
4 Aux feeds to the floor.

I intend on setting up a self mix option for the artists. Ill provide four mini mixers (Behringer UB802) to the recording floor. Feeding each mixer with 4 audio stems. Each artist (rarely record over 4 at a time) can them tailor thier own foldback mix. They use the built in headphone amp.

Problem Splitting each aux send to the floor x 4

I was wanting to introduce a patchbay. The Behringer PX2000 offers a parralell mode, it takes the input from the top terminal and interconnects it to the remaining three terminals of one module. So I get a 1x3 split. I can take one split and route it to another module and affectively have a 1x5 split. I'll end up using two modules per stem, but thats ok.

This was working out well, till I learnt that the particular patchbay in question has unbalanced interconnects.

I was also hoping to use the patchbay to patch microphones (understanding the perils of the same, but hoping to get lucky). With all sixteen stage feeds coming to the patchbay, and me having the flexibility to route them to whichever pre/DAW input i desire. I do not own a mid/large format 8 Bus console, so this flexibility would be very nice.

What are my best options ? I have now called for a balanced patchbay. This will atleast take care of the mic patching issue. It however does not offer the parallel mode. I can still split using a half normalled configuration, but this would eat up too many modules.

How do i deal with splitting the aux signal x 4. Will a simple cord split into 4 outputs do ? (much like an extended Y cable)

Thank you very much and a very happy new year to all!

Cheers!
Sidhu

many choose NOT to put Mic levels on the patch panel
but some do
I prefer to use an XL3 panel for changing Mic feeds

I have parallel'd microphones
but very rarely
and it was using an XL3 Y cord

" How do i deal with splitting the aux signal x 4. Will a simple cord split into 4 outputs do ? (much like an extended Y cable) "

you want to feed 4 Behringer UB802 mixers
with
4 audio stems .... from what ?

if this device is 600 ohm spec'd output or just has a healthy current capability then
with the input to the UB802 mixers at ... perhaps 10 to 20k
I think it could work ... and probably work fine.

Try it
it can only ... not work and then you will need to find a Distribution Amp or equivalent.

Thanks a ton Kev!

Well, Let take the example of a recording setup.

I am recording a drummer, Guitarist, bassist and vox.

From my session, I have four aux feeds going to the floor.

Aux 01 is Kik/Click
Aux 02 is Guitar
Aux 03 is Bass
Aux 04 is vox

On reaching the floor, the feeds are routed to their respective channels on the UB802 with the drummer. So the drummer wants a lot more kick in his can, he mixes it in himself. He can even do a little EQ if he likes. :-).

I now want to take a split of all 4 auxes and give similar four channel feeds to the guitarist too... He does his own submix, and so-on...

A bit fancy, and i can pretty much do it myself, but fancy is sometimes nice....

cheers!

Oh I'm extremely sorry! I dint read you correct. (read as 'for what' )

The outputs will be coming off the DAW, through the E-mu 1820 interface (balanced) or alternatively via a lightpipe connection to the ADA8000 (also balanced)

Thanks again!

a quick google on the E-mu 1820
8 balanced or unbalanced outputs (+4 or -10)
I can't find a spec for max output and if it is true 600ohm

and I own an ADA80000

I think both units have enough grunt to try the multi Y cord
you could try either balance or unbalance

but the inputs to the UB802 could be more of an issue
" 6 balanced high-headroom line inputs "
but no info on the input impedance
I'll guess they are high ... (bridging)

try some single pair shielded cable with the 5 TRS connectors
try without the sheild connected at the 4 TRS connectors
don't chop off the shield drain wire as you may want to use it later

if there is hum ... connect just one sheild

make sense ?

Kev wrote:
but the inputs to the UB802 could be more of an issue
" 6 balanced high-headroom line inputs "
but no info on the input impedance
I'll guess they are high ... (bridging)

try some single pair shielded cable with the 5 TRS connectors
try without the sheild connected at the 4 TRS connectors
don't chop off the shield drain wire as you may want to use it later

if there is hum ... connect just one sheild

make sense ?

Took a couple of reads.. but yeah im good! Thanks a ton ! Ill keep u posted.

Should i initially try with the sheilds connected to the 4TRS connectors also, or is that sure to cause ground trouble ? I dont understand ground troubles at all.... Also, a single pair sheilded cable = Twin core cable (like a microphone cable)

Also, I dont understand the 'Bridging' part. Is it revelant in this dicussion ? Thanks!

8-)

yep on the twin core ... but it is smaller than the average Mic Cable

a line level installers cable that has a foil or braid with a drail wire for easy soldering or kroning

belden have both single pair and two pair cables for the job
so do others

to ground or to not ground
:)
today my gut feeling is go Groundless
you can easily connect one or all of them later

but I have been know to change my mind

ALL installations are best done in context
... that can't always be done but in a small music studio you can afford to test many of the options and pick the best for your situation.

Bridging Input is probably only an audio term but it does have a specific meaning
it is mostly to do with impedance and the attempt to remove the need for correct loading

Low imp outputs into High imp inputs
this will allow single outputs to feed multiple inputs

google
bridging audio Input
and you get

http://www.jensentransformers.com/an/ingenaes.pdf

I haven't read this one ... but

ALL of the Jensen stuff is worth a read ... and a print
AND
the same goes for the RANE library and notes

do it do it do it

ah hah !!
here is a better one
google
bridging audio Input impedance

http://en.wikipedia.org/wiki/Input_impedance
and
http://en.wikipedia.org/wiki/Impedance_bridging