I Need Serious Help With Patch Bays

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crawdad

crawdad

Dammit, Jim, Shut Up!
I'll begin with a brief description of what i want to do. I am planning to upgrade my studio to be able to record 16 tracks simultaneously. I want to mix outboard pre's with board pre's and be able to monitor all this without latency (thus I want a 24 channel board, at least).

So, after mulling all this over this morning, I have decided that I need a well done patch bay system. It will need to be TRS balanced and I'm figuring that means TT cables and all. I will have 16 tracks going to a pair of Motu 2408 MKIIs or something in that ballpark. I will need to monitor and record from the board pre's, outboard pre's and various synths, samplers and drum modules as well as an occasional guitar modeler. I will need to patch in things like an RNC, Composer, possible effects unit, etc.

Questions:

1. Can I mix balanced and unbalanced lines on one patchbay? For example, can I patch an unbalanced synth output to a balanced input on the MOTU 2408? Or should I have one interface and bay dedicated to unbalanced feeds and another for just balanced signals? Some of my equipment is balanced and some of it isn't.

2. Please put my feeble mind out of its misery and explain what is "normalled" "half-normalled" and open. I don't know why I can't understand this becasue I'm sure its simple. Maybe I am too!

3. Is there a preferred brand of cable to use? I can solder and I understand the basics of TRS wiring. I assume that for unbalanced signals, I could simple wire those jacks as hot and ground. I am a bit confused on the concept of getting phantom power to the mics. (are you laughing at me yet?!)

Look, I will stop there. That is a bunch of questions already. Any nudge to get me on my way and seeing this clearly would help a whole lot. My goal is to put together a working environment where all patching is done at the patch bay. As it should be. Thanks a lot and I will check back in with, hopefully, some intelligent questions.
 
crawdad said:
I'll begin with a brief description of what i want to do. I am planning to upgrade my studio to be able to record 16 tracks simultaneously. I want to mix outboard pre's with board pre's and be able to monitor all this without latency (thus I want a 24 channel board, at least).

So, after mulling all this over this morning, I have decided that I need a well done patch bay system. It will need to be TRS balanced and I'm figuring that means TT cables and all. I will have 16 tracks going to a pair of Motu 2408 MKIIs or something in that ballpark. I will need to monitor and record from the board pre's, outboard pre's and various synths, samplers and drum modules as well as an occasional guitar modeler. I will need to patch in things like an RNC, Composer, possible effects unit, etc.

Questions:

1. Can I mix balanced and unbalanced lines on one patchbay? For example, can I patch an unbalanced synth output to a balanced input on the MOTU 2408? Or should I have one interface and bay dedicated to unbalanced feeds and another for just balanced signals? Some of my equipment is balanced and some of it isn't.


This is not a problem, mix and match as you feel like.

2. Please put my feeble mind out of its misery and explain what is "normalled" "half-normalled" and open. I don't know why I can't understand this becasue I'm sure its simple. Maybe I am too!

Read this: javascript: newWindow = openWin('proddetail.cfm?id=PX2000&type=310&lang=eng', 500,420); newWindow.focus();


3. Is there a preferred brand of cable to use? I can solder and I understand the basics of TRS wiring. I assume that for unbalanced signals, I could simple wire those jacks as hot and ground. I am a bit confused on the concept of getting phantom power to the mics. (are you laughing at me yet?!)


Mogami is a widely used , great cable..


Look, I will stop there. That is a bunch of questions already. Any nudge to get me on my way and seeing this clearly would help a whole lot. My goal is to put together a working environment where all patching is done at the patch bay. As it should be. Thanks a lot and I will check back in with, hopefully, some intelligent questions.
 
1. Yes. A patch bay that can handle balanced can also handle unbalanced.


2. http://php.indiana.edu/~lrobins/mixbay.htm

3. Patch cables are no different from other cables, except that you need a lot of them, and you need a lot of cables to connect your patchbays to your equipment. If you want to spend several weeks soldering 24/7, then that's your problem. :)
I'd recommend you buy them. Choice of cable brands is a purely religious affair into which I will not venture since I am an atheist and do not feel like being flamed today.
 
Thanks guys for the help. The article that regebro posted a link for is very enlightening and will help me a great deal in setting my patchbay up properly.

Let's see: about 8 miles of mogami and 100 pounds of solder should do it.... :p
 
Crawdad, just inside my controll room, I have around 3800' of Beldon 8451, two 52 point and three 44 point Switchcraft 2600 patchbays. I soldered at least 4 hours everyday for a little over three weeks. It's gotta be a labor of love.:D
 
in addition to the good advice already given...

A typical multi-track configuration is as follows...

PB1
Top row - "hard-wired" sound source OUTPUT
Bottom-row - Mixer channel INPUTS
(top is normalled to bottom)

PB2
Top-row - Mixer Insert SENDS
Bottom-row - Mixer Insert RETURNS
(top is normalled to bottom)

PB3
Top-row - Mixer BUSS OUTS
Bottom-row - Multi-track INPUTS
(top is normalled to bottom)

PB4
Top-row - Multi-track OUTPUTS
Bottom-row - Mixer multi-track RETURNS
(top is normalled to bottom)
 
Re: in addition to the good advice already given...

Blue Bear Sound said:
A typical multi-track configuration is as follows...

PB1
Top row - "hard-wired" sound source OUTPUT
Bottom-row - Mixer channel INPUTS
(top is normalled to bottom)

PB2
Top-row - Mixer Insert SENDS
Bottom-row - Mixer Insert RETURNS
(top is normalled to bottom)

PB3
Top-row - Mixer BUSS OUTS
Bottom-row - Multi-track INPUTS
(top is normalled to bottom)

PB4
Top-row - Multi-track OUTPUTS
Bottom-row - Mixer multi-track RETURNS
(top is normalled to bottom)

PB2 and PB4 I understand completely. I have a couple of questions about the other two.

First, in PB1, are the hard wired sound source outputs connected to the mic cables, line outs of synths and so forth? The reason I ask is that I saw one example where the main snake (16 channel) went directly to the mixer, then the direct outs from the mixer went to the top row of PB1. I would prefer to be able to route the incoming mic lines, etc, to some external pre's. Which way is the best, or most widely used?

Second, in PB3, you say BUSS OUTS. I assume you mean something like the 8 busses on a Mackie 24x8x2 console, right? I imagine that 8 buss is as much as I can afford. What do you do when you want to record 10 tracks? Are the direct outs of all the mixer channels also on this bay? I will have 16 multi track inputs and outputs. Might as well be able to use all of them.

Thanks for the information. My goal is set up the patch bays so that any engineer could come in and do a session, being comfortable with a standard patch bay setup.
 
My head was spinning about this same thing awhile back. I just could not picture how these things were wired inside or how they worked.

The only type of patch bay I had ever used was open configuration.

I got straightened at this site:All about patch bays
 
Re: Re: in addition to the good advice already given...

crawdad said:
First, in PB1, are the hard wired sound source outputs connected to the mic cables, line outs of synths and so forth? The reason I ask is that I saw one example where the main snake (16 channel) went directly to the mixer, then the direct outs from the mixer went to the top row of PB1. I would prefer to be able to route the incoming mic lines, etc, to some external pre's. Which way is the best, or most widely used?
Yes -- you can simply hard-wire all common sources - synths, drum machines, sound modules, to the top-row, meaning they normal to the bottom row which are your mixer inputs.... this allows you to maintain ommon sources but yet you can simply plug somwthing directly into the bottom row channel input if you want to put something else there (this will cut the top connection)

It's very flexibile, and you don't have to re-patch your most commonly used sound sources....


crawdad said:
Second, in PB3, you say BUSS OUTS. I assume you mean something like the 8 busses on a Mackie 24x8x2 console, right? I imagine that 8 buss is as much as I can afford. What do you do when you want to record 10 tracks? Are the direct outs of all the mixer channels also on this bay? I will have 16 multi track inputs and outputs. Might as well be able to use all of them.
Yes, another patchbay will be used to connect the mixer direct outs....

In reality though, you wouldn't want to use the BUSS outS to connect to your multitrack unless you were doing a reduction of channels to tracks (ie 8 drums down to 4 tracks)... normally you would patch the output of your preamp directly to the appropriate multi-track inputs, bypassing the console altogether!
 
Ah! Its crystal clear now! I see how the whole layout works. Thank you very much for all your help Blue Bear--and everyone else too. I can move to the next phase now--getting all the cable and patch bays. Its gonna be a BIG job to put it all together, but I know it will be worth it in the end.

If I may, one final question. Its my impression that a TT bay, with patch cables, is going to cost more than a 1/4" bay. Since I already have two very hefty 1/4" bays with the big metal jacks, I am leaning toward getting two more of the same. These are 24x2 bays.

What are the pro's and cons of sticking with 1/4", other than having fatter cables? I see the TT stuff in the big studio's. Is it just the smaller size of the bays and cables or is there more to it? By the way, I can solder and do the wiring myself, so I can hopefully cut the cost of cables by rolling my own.
 
Size mostly.... less heavy cable lying about....

A good connection is a good connection, whether TT or 1/4"!

as an example - here's my PB config -- all are 48-point, 1/4" balanced bays (RE'AN)

PB1 top: sound source OUTs
PB1 bot: mixer INs(half-normalled top/bot)

PB2 top: mixer insert SENDs
PB2 bot: mixer insert RETs
(half-normalled top/bot)

PB3 top: mixer buss OUTs
PB3 bot: multi-track INs
(half-normalled top/bot)

PB4 top: multi-track OUTs
PB4 bot: mixer tape RTNs (Mix B INs)
(half-normalled top/bot)

PB5 top: mixer direct OUTs
PB5 bot: miscellaneous
(de-normalled top/bot)

PB6 top: outboard I/O
PB6 bot: outboard I/O
(misc. normalling top/bot)

PB7 top: mixer buss SENDs + misc outboard I/O
PB7 bot: mixer buss RTNs + misc outboard I/O

PB8 top: mixer aux SENDs + outboard reverb OUTs
PB8 bot: outboard reverb INs + mixer aux RTNs
 
That is a SERIOUS number of patch bays there Blue Bear! I suppose as the studio grows, so do the number of patch points needed! I see you are moving into some new digs soon, by the way.

Well, I think I may stick with the 1/4" bays. The connection IS the same and I already have some of the gear, so...might as well continue on in the same direction. Thanks again!
 
Blue Bear Sound said:
Size mostly.... less heavy cable lying about....

A good connection is a good connection, whether TT or 1/4"!

Well, I was happily nodding in agreement about most of the advice until we got here!

The biggest difference between a TT patch bay and 1/4" is the quality and ruggedness of the connections. A TT patchbay was designed for early telephone switchboards (hence the name: tiny telephone) where patch cables were plugged in and pulled out of the patch points hundreds of times per day, day after day, year after year. With luck, a good TT bay will last you for decades without giving you a hint of a problem.

If you use 1/4" bays, on the other hand, it's not a matter of IF you will start losing patch points, it's more a matter of WHEN. A lot depends on how much plugging and unplugging you do, of course, but they just aren't designed with anywhere near the same level of "military grade" robustness that your typical TT bay has.

The other main difference between 1/4" bays and TT bays is that the rear connections on a TT bay are hardwired, whereas on a 1/4" bay you are just plugging 1/4" plugs into 1/4" jacks, same as on the front. Your rear connections on a 1/4" bay should be checked periodically to see if they are still firmly plugged all the way in.

It's nice a nice feature that TT's take up less room per connection in your rack. But given that you pay a LOT more for the bays AND the patch cables, that is hardly a compelling reason to go with the TT format. It's the reliability and quality of connection that is the reason why all the top pro studios use TT bays. While I use TT bays for all my main connections, I also have a couple of 1/4" bays wired into my TT bays so that I can quickly plug in things like extra synths from my road rack, or other equipment that the client may bring with them.

The other part of your question that raises a red flag was your question about phantom power. Phantom power is only an issue on your preamp inputs. I do not recommend wiring your preamp inputs into a 1/4" (or TT) patch bay. If you need to set up a patchbay for your mic inputs, use an XLR one, such as a typical stage snake.

Preamp OUTPUTS, on the other hand, are excellent candidates to be run through your patch bays.

I didn't read the links people posted explaining normal, helf-normal, parallell, and open connections... but I'm assuming from your response that those questions have been answered. I would just add that you should carefully plan your patchbays on paper first. Your main considerations are using normalled/half-normalled connections to set up the most common "default" routings so you won't have to plug a patch cable in every time. (For instance, Tape Channel 1-16 outputs into Mixer Tape Returns #1-16). You would use open connections to help minimize the chance of setting up accidental feedback loops when you unplug a patch cable.

Good luck... hope this helps!
 
I agree 100% LD.....!

My comment was based on the likelihood that most home-rec's requirements don't require the additional robustness of the TT bays.... nor are most willing to incur the extra expense!

LD is absolutely right about the loss of points -- although in practice it hasn't been a big deal for me - I have a whack of replacement modules -- in 3 years I've only ever had to replace 1!
 
Don't forget the original 1/4" longframe telephone-type patchbays, which are what I use. They are much less expensive than the TT/bantam bays, they are just as robust, and the larger format makes them much easier to solder up. You can quite often get them at surplus store, at hamfests, or on the used market from radio and TV stations as they upgrade equipment. Thre tradeoff for the lower density is that you can actually read the labels as well- which is important for those of us who have reached bifocal age (;-).

Not all 1/4" bays are shortframe prosumer jack-front-and-back units: there's still a lot of life left in the full-size 1/4" telephone style format yet!
 
littledog said:


The other part of your question that raises a red flag was your question about phantom power. Phantom power is only an issue on your preamp inputs. I do not recommend wiring your preamp inputs into a 1/4" (or TT) patch bay. If you need to set up a patchbay for your mic inputs, use an XLR one, such as a typical stage snake.

Preamp OUTPUTS, on the other hand, are excellent candidates to be run through your patch bays.

Just when I thought I was out of the woods! This changes my approach. Is the idea of phantom power on the patch bay bad because of risk of a possible short? Or does the phantom power somehow distribute itself across channels somehow? I was under the impression that I could run all my mic cables into a normalled bay directly to my preamp inputs. Then, I could break that connection, send the mic signal to an outboard pre and on to my recorder input.

Skippy--I have two 48 point telephone style bays and they seem to be bulletproof. I have used them so far just with open connections, no problems.
 
Crawdad - I don't know shit about this stuff, or I didn't, but the issue of phantom power was discussed in the thread linked-to above. It's several pages and I don't remember the answer but I know it's there. It had to do with hot-switching and I think it was skippy that provided the warning.
 
crawdad said:

I was under the impression that I could run all my mic cables into a normalled bay directly to my preamp inputs. Then, I could break that connection, send the mic signal to an outboard pre and on to my recorder input.

.

Were you going to replace all the male XLR connectors on your mic cables with 1/4" TRS just so you could plug mic cables into a 1/4" patchbay? Doesn't seem worth it to me.

Get a 16 or 24 channel stage snake with a box at one end and a fan at the other. Plug the fan end into all your mic preamp inputs, and just plug your mic cables into the appropriate input on the box.

Then use the 1/4" bay for your preamp outputs so you can route them to whatever tape track you desire.

For a more aesthetic solution, companies like REDCO will custom make you a rack-mountable XLR patchbay with exactly the length cables you desire hardwired to the back with the exact connector types you request already attached.
 
Yup. Phantom power and TRS patchbays do not mix. Here's what I said about it in that older thread, https://homerecording.com/bbs/showthread.php?s=&threadid=25365 :

I pretty well skirted the issue of mic lines in the patch bay, trying to keep it a little simpler. The short answer is "they don't go there": my TRS patchbay is all line-level-signals only. All the mic patching I handle separately, because I don't believe in putting phantom power on TRS jacks, telephone or otherwise, unless I absolutely cannot help it. I sure don't want such a thing to be part of my basic default setup...

TRS jacks momentarily short tip, ring, and sleeve as they are disconnected. That makes for an easy way to blow up both mics (NEVER hotpatch a ribbon mic...) and phantom supplies, not to mention the damage to the monitors if the gain is up when you hotpatch: the resulting pop can and will put your cones in orbit. Hotpatching mics is a crime against nature, but in the heat of the moment, it's going to happen.

It also ain't much fun to mistakenly patch a mic input with +48v phantom onto another line input with raw opamp inputs powered by say, +-15v. The input protection diodes go, and you just killed that input... Not good. So I eliminate that hazard by not *allowing* it to happen, except in very limited extreme situations.

And even that is a lie: on two occasions so far, I've needed 4 mics up in the living room. So two go on the XLR mic lines, and I repatch two line sends with TRS/XLR kluge cables on each end. But I do not do that except when I absolutely have to, and when I know that the talent will not "try to help" by randomly plugging this into that. And I cringe the whole time anyway. Old habits die hard.
 
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