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I've already spent too many hours on this, but...

I've purchased a 96 point TT patchbay. I've ordered a couple of the db25 sub cables. Before I get too far along, I'd sure appreciate any thoughts/additions/deletions anyone would be willing to add.

Thanks in advance.

CH 1-24

CH 25-48

WZ3 is the Allen & Heath 16:2 WZ3 that I am considering using for OTB summing (bad idea?)

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RecordingDude Thu, 04/28/2016 - 18:14

Thanks audiokid.

I'm good on understanding of normal/half normal/no normal and all my gear and cables are balanced, so no issues there.

I'm also not planning to hook up instruments, just trying to make it easier to use the mic preamps, outboard compressors and channel strips, as well as (potentially) using an outboard mixer for summing.

fwiw, the patchbay I'm using is the Redco R196-D25PG.

RecordingDude Fri, 04/29/2016 - 18:21

Here is the current version.

Patchbay v.2

I'm making the mic input to preamp input half-normal so I can also run it to the mixer to enable multitrack recording of rehearsals. If I do that, I'm thinking it will need to involve only dynamic mics, is that correct (due to phantom power?)

What is the advantage of using full versus half normal? If the preamp or DAW input is receiving signal it's not using, is any harm being done?

DonnyThompson Sat, 04/30/2016 - 03:54

RecordingDude, post: 438177, member: 49834 wrote: If I do that, I'm thinking it will need to involve only dynamic mics, is that correct (due to phantom power?)

Well, you can patch Phantom Power through a standard TT bay, but you have to be really careful to NEVER patch while the Phantom Power on the desk or preamp is ON ...
If the PP is on, and you are using a TT cable, when you insert it, the tip of the cable will momentarily connect with the ring contact in the jack, and the ring of the plug will touch the sleeve. This shorts-out the phantom supply, which then sends the PP voltage line directly to the ground - and, while the phantom supply source itself would likely handle this momentary spike, that voltage being routed back to the preamp or desk could cause damage to the channel input. It might not totally wipe out a channel input, but at the very least, it could cause that channel's input circuitry to take a bad hit, and could degrade the optimal performance pretty fast.

Truthfully, if you are looking at using a bay for mic inputs, your safest bet is probably to get an actual XLR bay.
XLR jacks are designed as such so that the ground - pin 1 - will physically contact first, with the two signal pins connecting just after, which then shuts down any chance of the PP supply being shorted out and routed back to the desk or preamp.

Still ... to be safe, you should get into the habit of making sure that the PP is off on the desk or pre before you patch. ;)


DonnyThompson Sat, 04/30/2016 - 05:28

RecordingDude, post: 438193, member: 49834 wrote: Excellent. Now I've ordered a couple of DB25 snakes I won't need, but this is def the better solution.

Based on my own past experience with patchbays - having added several more to the original patch count over time to accommodate new gear that I acquired through the years - I'm sure they will prove to be useful to you eventually... ;)

DonnyThompson Sun, 05/01/2016 - 02:46

RecordingDude, post: 438203, member: 49834 wrote: I'm thinking no harm to signal going to an input (DAW or mixer) that is not turned on. Is that correct?

I'm not quite sure exactly why you would want to route a signal to a device that isn't turned on... but no, if the patch points are all solid and all contacts firm, then no, there's no problem.

RecordingDude, post: 438203, member: 49834 wrote: Also, I'm using half normal so that I can both feed the DAW and mixer.

You could also use the "mults" we've discussed previously for this purpose - as that's what these are there for - routing one signal to multiple destinations.

As a side note - it's kinda tough for these old eyes to see every detail of your patch bay ( and I'm in dire need of new glasses, LOL), so I can't tell if you've added a digital I/O patch point to your bay or not, but if you have, or are thinking about doing so, you might want to avoid connecting an RCA/75 Ohm Digital Audio Cable via patch point - as these hate to be interrupted in any way... (this also includes using "extender" couplers).

I'm not saying unequivocally that you'll definitely have an issue if you choose to do this - You might be okay with connecting a digital cable this way - but in my own experience, this particular type of cable is best left alone, with a continuous run, and not interrupted by any kind of junction/connection or break/patch point between I/O source and destination.


RecordingDude Sun, 05/01/2016 - 05:15

D -

Thanks again for your thoughts.

Not using any digital i/o at this point - so no pb points dedicated.

Also no RCA.

All connections are balanced analog.

Thanks for your advice on running mics through the pb. I will instead have a wall/floor box that will run directly to the preamps/channel strips.

As far as sending signal to a device that is not turned on - I'm just trying to determine the advantage (if any) of using full versus half balanced inputs.

Lastly, I re-did the pdf so it should be easier to read (bigger font with bold.)


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