Music Player Network Home Guitar Player Magazine Keyboard Magazine Bass Player Magazine EQ Magazine
Topic Options
#2881728 - 09/26/17 01:36 PM Franken-cable conundrum
Stokely Offline
Platinum Member

Registered: 12/15/12
Posts: 1580
Loc: Florida
Hello, a minor problem in the overall scheme of things but I welcome opinions.

I have just about figured out how to go mixerless for "our PA" gigs--this would eliminating a submixer TO FOH, and eliminating the same mixer as a monitor mixer (as I know some others do). All I'd have to do is run 4 cables to/from FOH, which is one stage; no mixer on a board under my stand, just my Behringer P1 headphone mixer which I would velcro under my bottom keyboard. My iems plug right in and bam.

The one gotcha is simply one of connections and a weird design decision by Behringer IMO. It's also a complication caused by me wanting to run stereo monitors. I'm using a stereo TRS feed from our board for monitors. One 1/4 balanced cable runs back to me from the board. The darn Behringer has two XLR inputs (?!).

With my mixer, here's how it connects: split the TRS into two 1/4 using an adapter; those two 1/4 signals run into my mixer; the mixer main outs go to the Behringer using two 1/4 to XLR cables. (I use the aux out to send signals to FOH, obviously you don't want to send the two monitor feeds back to FOH!) Works fine this way, but I'm trying to eliminate the mixer and this is the last challenge!

So, what's the best way to get from a TRS end to two XLR male ends? I'm thinking the simplest--avoiding adapters as much as possible-- would be to order a custom TRS-to-XLR cable. That gets from FOH to me. Then one adapter that splits the XLR to two.
I haven't been able to find one Y adapter that goes from female TRS to two XLR male ends...
I could resort to two adapters, using a standard TRS cable: TRS > XLR > XLR breakout
OR....use a standard mic cable and use an adapter on both ends: TRS-to-XLR adapter > mic cable > XLR breakout

Anyway, long post about a minor issue. I wish that Behringer used 1/4 inputs though.

Top
KC Island
#2881732 - 09/26/17 02:05 PM Re: Franken-cable conundrum [Re: Stokely]
GRollins Offline
Senior Member

Registered: 09/01/17
Posts: 203
If you're handy with a soldering iron I can walk you through this.

Typically Pin 1 of an XLR is ground. It's also a good idea to ground the shell, assuming that it's metal (e.g. Switchcraft; some companies use plastic).

Pin 2 is going to be either + or - and honestly, it doesn't matter which you choose as long as you're consistent from channel to channel. It's probably +, so let's assume that it will be used.

Pin 3 will be the opposite of Pin 2. Assuming you're using Pin 2, leave this one alone.

So...

Both Pin 1s (aka grounds) go to the shaft of the TRS.
One Pin 2 goes to the tip of the TRS.
One Pin 2 goes to the ring of the TRS.
Both Pin 3s are open.

Simple.

Or you can pay someone. Your choice.

Grey

EDIT: I actually wish everyone would use XLRs. Balanced lines pick up less noise.


Edited by GRollins (09/26/17 02:07 PM)
_________________________
I'm not interested in someone's ability to program. I'm interested in their ability to compose and play.

Top
#2881734 - 09/26/17 02:20 PM Re: Franken-cable conundrum [Re: GRollins]
Stokely Offline
Platinum Member

Registered: 12/15/12
Posts: 1580
Loc: Florida
I am not. I specced one at redco and it was very reasonable for amphenol connectors and their house cable.

So do you recommend such a TRS-to-XLR cable and then a breakout adapter (to send to two XLR ends)?

Top
#2881737 - 09/26/17 02:35 PM Re: Franken-cable conundrum [Re: Stokely]
WesG Offline
MP Hall of Fame Member

Registered: 02/16/13
Posts: 3015
Loc: Inverary, ON, Canada
Pro audio doesn't generally have the concept of stereo - everything is essentially dual mono. As such, any XLR to TRS cables or adapters that you're likely to encounter will be balanced to balanced, not really what you're looking for.

The PowerPlay P1 is cheap enough, though, that if you were going to run stereo all the time...........I would be tempted to modify it so that it only has one input, and that input is unbalanced stereo.

Wes
_________________________
Hammond: Split L111, '58 M3, '59 B3, Northern DV
Leslie: 760, 51C, 147, 145
Yamaha: CP4, DGX-620, DX7II-FD-E!, PF85
Roland: VR-09
Band Site: http://DrBombay.ca/

Top
#2881744 - 09/26/17 03:07 PM Re: Franken-cable conundrum [Re: WesG]
Stokely Offline
Platinum Member

Registered: 12/15/12
Posts: 1580
Loc: Florida
actually, dual mono is indeed what I have. It's two different mono monitor mixes, and every instrument is mono...so essentially all the stereo does for me is allow me to pan the mono instruments apart a bit (by an instrument being more or less in the first or second monitor mix). I run the P1 in "stereo" mode, which pans the two inputs L and R.

I could just set it to mono and use one input, actually it's not like I pan things that hard to begin with. Keys 1 at 11am, Keys 2 at 1pm, guitar at 3pm etc. It does let me reduce volume that little bit more since things can have their own space, but it's not critical. I realize that is different from what you suggested, your idea (if I could pull it off) would be ideal.

Top
#2881753 - 09/26/17 03:25 PM Re: Franken-cable conundrum [Re: Stokely]
WesG Offline
MP Hall of Fame Member

Registered: 02/16/13
Posts: 3015
Loc: Inverary, ON, Canada
I think the most correct way to do what you want would actually be with a two-channel snake cable. Put two XLRs on each end. Colour-code the ends. Badda-bing, badda-boom. If you can't make them up, Chris at Redco can.
_________________________
Hammond: Split L111, '58 M3, '59 B3, Northern DV
Leslie: 760, 51C, 147, 145
Yamaha: CP4, DGX-620, DX7II-FD-E!, PF85
Roland: VR-09
Band Site: http://DrBombay.ca/

Top
#2881845 - 09/27/17 06:50 AM Re: Franken-cable conundrum [Re: WesG]
Stokely Offline
Platinum Member

Registered: 12/15/12
Posts: 1580
Loc: Florida
I did consider a custom snake, and I'd make it big enough for the other signals going to FOH (2 keyboards, 1 mic).

Problem is, the monitor out of the Touchmix is one TRS, so I'd still have to go from that to the two XLR.

Before I make a custom cable that might not be useful due to pin config (I've gotten some advice here and another forum that this might be a problem), I think I'll get a couple adapters and use a standard cable. That way if it doesn't work those adapters are always good to have.

If it doesn't work or is a hassle, I can always go back to using my mixer, or maybe just use a mono monitor mix (which works fine, the ability to pan in my IEMs is just icing on the cake).

Top
#2882002 - 09/28/17 12:38 AM Re: Franken-cable conundrum [Re: Stokely]
stoken6 Online   content
Platinum Member

Registered: 05/12/12
Posts: 1502
You want something like this? (Studiospares Pro Neutrik Stereo Jack 2x Unbalanced XLR Male Splitter 3m).

If you need longer, simply add a couple of conventional XLRs.

Cheers, Mike.
_________________________
AX48.PM351.FC7.VFP2
One or two keyboards.

Top
#2882025 - 09/28/17 04:45 AM Re: Franken-cable conundrum [Re: stoken6]
WesG Offline
MP Hall of Fame Member

Registered: 02/16/13
Posts: 3015
Loc: Inverary, ON, Canada
Why would you want more than two channels in the snake going to your belt pack?

It's too bad your touchmix only has a headphone output. Most mixers I've used have left/right control room outputs.

If you DO make a custom cable and are worried about it being wired up wrong............just don't make it wrong? If you're unsure about how to make it right, post. But be very clear about what you're doing when you do.

Wes
_________________________
Hammond: Split L111, '58 M3, '59 B3, Northern DV
Leslie: 760, 51C, 147, 145
Yamaha: CP4, DGX-620, DX7II-FD-E!, PF85
Roland: VR-09
Band Site: http://DrBombay.ca/

Top
#2882032 - 09/28/17 04:58 AM Re: Franken-cable conundrum [Re: WesG]
Stokely Offline
Platinum Member

Registered: 12/15/12
Posts: 1580
Loc: Florida
I only meant that I'll have 3 other cables going from my rig to the board, so they could be part of the same snake if I make one (2 keys and 1 mic). I have this now with some split-sleeve casing for convenience.

I got a suggestion from our sound guy that he can route the stereo monitor feeds to the monitor outs, which will drive headphones directly. There is a limiter on the monitor out, but that's my main concern if I go directly from monitor out to my earphones (giving up the limiter right at my pack). I'll still have overall volume control via my phone. Would that in-mixer limiter provide enough protection in your opinions? Seems like it would against feedback and mic drops (things up the signal flow) and I'd only be vulnerable to something after the mixer, and there wouldn't be much there, just one cable (?)

I do appreciate all the advice. I think before things go too complex I'd just fall back to a one-cable XLR and keep monitors mono, which has worked for maybe 100 gigs in the past few years smile Stereo is nice but not a must-have.
I'd probably contact the folks at redco about a custom snake if I get one, and post here as well to make sure I covered everything.

Top
#2882236 - 09/28/17 06:52 PM Re: Franken-cable conundrum [Re: Stokely]
WesG Offline
MP Hall of Fame Member

Registered: 02/16/13
Posts: 3015
Loc: Inverary, ON, Canada
I would not rely on the limiters in your mixer. Even if the "aux outs" will drive headphones directly, it is unlikely that they are limited anywhere near the right place.

Even the Powerplay Monitor is a bit iffy -- not adjustable to match the headphones -- but way better than nothing.
_________________________
Hammond: Split L111, '58 M3, '59 B3, Northern DV
Leslie: 760, 51C, 147, 145
Yamaha: CP4, DGX-620, DX7II-FD-E!, PF85
Roland: VR-09
Band Site: http://DrBombay.ca/

Top
#2882278 - 09/29/17 05:58 AM Re: Franken-cable conundrum [Re: WesG]
Stokely Offline
Platinum Member

Registered: 12/15/12
Posts: 1580
Loc: Florida
Thanks WesG. That is my gut feeling as well.

I'm a bit confused by "near the right place" though. Do you mean in the signal chain? I would think the limiter would be on the output of the mon send, post-level of the instruments in the mix (?)

Or do you mean level-wise it's not enough to stop spikes?

Thanks.

Top
#2882285 - 09/29/17 06:15 AM Re: Franken-cable conundrum [Re: Stokely]
WesG Offline
MP Hall of Fame Member

Registered: 02/16/13
Posts: 3015
Loc: Inverary, ON, Canada
No, I mean level-wise - and maybe speed, too. Many PA limiters (like dbx's "Over easy" units) will allow a brief spike over the limit. This is more musical, and not really hard on loudspeakers as a brief bump won't make the voice coil heat up.

Which brings us back to function, the limiter you need for a loudspeaker is to prevent over-excursion of the cone and heating of the voice coil. This limit is based on the physical characteristics of the loud speaker, combined with the gain of the amplifier.

The limiter for in-ears is to prevent hearing damage, so it should probably be faster on the spikes. The amount of limiting needed is dependent on the efficiency (sensitivity) of the IEM driver.

So, for example, the Shure SE215 has a sensitivity spec of 107dB. This means that if you provide a 1mW signal at 1kHz that the driver outputs 107dB SPL into your ear. The Ultimate Ears Pro 7, on the other hand, has a sensitivity of 124dB. This is a LOT louder.

http://www.shure.com/americas/support/find-an-answer/understanding-earphone-headphone-specifications

So I have no idea how the Powerplay P1 can know what SPL its limiting to. This might be an interesting question for Behringer support.


Edited by WesG (09/29/17 06:16 AM)
_________________________
Hammond: Split L111, '58 M3, '59 B3, Northern DV
Leslie: 760, 51C, 147, 145
Yamaha: CP4, DGX-620, DX7II-FD-E!, PF85
Roland: VR-09
Band Site: http://DrBombay.ca/

Top
#2882288 - 09/29/17 06:34 AM Re: Franken-cable conundrum [Re: WesG]
Stokely Offline
Platinum Member

Registered: 12/15/12
Posts: 1580
Loc: Florida
Wow, good info. I hadn't even thought about how all this really worked, I just thought "limiter".

Ironically I used the SE215 for a couple years and just upgraded to some customs made by InEarz here in Sanford...I should check on their specs.

In the back of mind with the Powerplay, which is a $49 unit, is: "just how effective is the limiter." It sounds like "maybe it isn't, it depends." The illusion of safety is dangerous. I'd guess that the one in my Shure pack is likely "better" but that's just based on brand and cost and not fact. All that said, it won't hurt to have it vs not having it, so that's what I'll do.

I am very wary about hearing damage. My buddy got his ruined at a church while wearing headphones plugged directly into a console. I also happened to be in a studio (as an intern, way back when) in Nashville with at least 15 session guys in various rooms...the engineer sent a huge blast of feedback through all their cans...wow. 15 cans went flying as they tore them off their heads....They were understandably PISSED.

Top
#2884714 - 10/12/17 07:55 PM Re: Franken-cable conundrum [Re: Stokely]
Synthaholic Offline
Platinum Member

Registered: 04/18/05
Posts: 1356
Loc: Where the wild things are
It's very simple to make a cable like this. I made these to solve the problem of a table-top mixer sitting in a 4 space rack - everything has to be right-angle because of limited height, and the mixer had no XLR Main Outs. The right-angle gold plated adaptors are from Radio Shack.

_________________________
The fact there's a Highway To Hell and only a Stairway To Heaven says a lot about anticipated traffic numbers

People only say "It's a free country" when they're doing something shitty-Demetri Martin

Top


Moderator:  Grave Bryce, Stephen Fortner