XLR splitter question

Hi all;

I have a “live” room connected to my “control” room via a snake. I have two preamps that represent a significant step up from the MR816 interface I’m using - all located in the control room.

Sometimes, I might want to access those preamps from the live room, but more often than not, I’ll want to access them from the control room (like a vocal session, etc.).

If I was to use an XLR Y-splitter in the input of my preamps, this would - at least technically - allow me to have one of the other ends connected to the snake to the live room at all times, while keeping the other end of the splitter handy for plugging stuff into from the control room, without having to pull stuff out and get around in behind the preamps/rack, etc.

Assuming that I wouldn’t be combining two signals at the same time - it would be an either/or situation - would there be any foreseeable problems with this approach in terms of signal loss/ signal quality?

Thanks!
Chris

Quality loss is more or less the same as using one input cable of length of these two input cables combined.

But definitely do not plug in 2 devices on at the same time even if not used at the same time. This can create huge loss of quality (depending on devices connected).

“Professional” solution would be to construct a simple patch-bay with which you could select between control-room source and live room source by plugging in a jumper cable. This would also prevent accidental usage of 2 equipmant at the same time.

Hey Jarno;

Thanks for your reply. The snake itself is 20 ft - so not that long, all things being relative. That said, most of my mic cables are also 20ft, so that makes a combined total distance of 40 ft. With XLR cables being balanced, would you say that is a problematic distance?

As far as having two devices plugged in at the same time, you wouldn’t consider the snake itself as a device, would you? As long as there is nothing plugged into the snake, It’d be the same as having nothing plugged into the other side of the Y, right?

Given this method of operation (pending how these questions are answered…), what would I gain by building such a patch bay over what I am doing now?

I’m not challenging you. I’m genuinely interested in knowing where my shortfalls are, if any, with this.

Thanks!
Chris

I’d second building a patchbay, as Jarno suggested.

Look for “NA3MDF” and “NA3FDM”, so you’ll understand the following signal path (only meant as an example):

The mic cable in the live room first goes to NA3xxx #01 in the control room. From there, you use a short XLR patch cable that goes to the NA3xxx #02, still in the control room. From there, a cable goes into the preamp in the control room.

Now, if you want to connect a mic in the control room to the preamp, you just unplug the short XLR patch cable and plug in the mic cable instead.

This solution has the adventage of not letting two things into the preamp at the same time. The NA3xxx thingies can be easily mounted into a 19" rack panel with D holes.

If you really need to connect two mics at the same time, use a D.I. box that combines two mic inputs (example: “The S-combine takes the inputs of two microphones and combines them into a single microphone level Output”), so the mics will be transformer separated. (I don’t know if that works correctly with phantom power, so be warned…)

I hope this was not too far away from your needs and plans. I use NA3xxx for built in mic gear that I can’t directly access. The advantage is that you can patch with regular XLR cables, and the system stays very flexible (in comparison to soldered versions).

I think I like that solution, OlderNotWiser.

I expect I’ll have to dig around a bit for the parts, but they should be around somewhere. (or get them on line, of course)

This got me thinking…

My Universal Audio 710 is a half-rack 2U preamp. There is a spacer that allows it to screw into a 19" rack. Could I just get a punch and put a couple of D holes in that spacer and make some use of some otherwise dead space?

The steel spacer - as best as I can measure it - is 3mm thick.

(I measured it by getting ten small washers and measuring them, which came out to 9mm. The thickness of the metal spacer is more than 3 washers and less than 4 washers - closer to 3.)

Thanks!
Chris

Wait a sec… If I was to punch those holes, I’d still need to somewhow drill 3mm threaded holes to take a machine screw to connect the jacks to the faceplate. Is that right?

Chris

Aw, man… feeling silly trying to wrap my head around something so simple. It might be cheaper and easier to just get something like this:

https://www.long-mcquade.com/14673/Pro_Audio_Recording/Mixers/ART_Pro_Audio/3-Channel_XLR_Balanced_Patch_Bay.htm#Description-tab

So, based on your description, I would hook it up like this…

https://docs.google.com/drawings/d/17u3lEQDAaJ8H_-CgFNGJzcoX1s8A1Oy0Rdaxyy14QFU/edit?usp=sharing

(sorry for the crude artistry… haha)

That would involve the mic cable, the snake, an extension to get the snake cable around front, another patch cord to get it around back, and then a patch cord to get it into the mic pre.

Would that be better than the mic cable, the snake, the Y connector, and into the pre?

…like this… https://docs.google.com/drawings/d/1SRgrtvp1RrpWOVfgR3sXrtGuMqabkmCRFn1759iw_c8/edit?usp=sharing

Or am I misunderstanding?

Thanks;
Chris

EDIT: I can see how using the right combination of the male and female connectors would be a neater solution, but does still add at least one more cable into the sequence…

mic; snake; patch; patch, instead of mic; snake; Y-cable

To me, the ART Patch Bay seems to fit well. Just lead one of its “outputs” to the preamp and plug the cable from the live room directly to the corresponding “input”. If you need to feed the preamp from the control room mic, unplug the live room cable and plug in the control room mic instead (—> no patch cable needed). This will leave space for two more preamps or one stereo preamp.

(What I was describing is a bigger patchbay that fits into a 19" rack. Advantage: You may plug and unplug everything one handed as the plate is fixed in the rack. With the ART, you’ll need to screw the unit to some furniture, or you will be forced to use both hands when changing the mic connections.)

Y-cables are good for splitting one output and connect it to two inputs. Connecting two outputs into one input with an Y-cable really isn’t a good idea (there are exceptions, but those do not apply here).

Okay. That makes waaay more sense. I think I’ll go with that. Thanks!

As far as a larger 19" patchbay, I only have the two outboard pres and they’re both mono, so I wouldn’t really have a use for such a thing.

Thanks again!
Chris