Using DP for Live Backing Tracks (Stems or Mix?)

[rickorick]

One more thing. If you can advance the room and talk to the sound man sometime that helps,
I work with an artist and he'll have me call and talk to the sound man and tell him what we have and special needs etc. Then you can find out what kind of monitors they have, the bigger
venues are stereo I find these days and sometimes they have stereo monitors and that's good for keys and tracks.

[dbawmp]

Hey James! I thought I'd share this thing I just built for a band I produced. It's a full redundant playback system. The Radial SW8 has -10 outs that can be plugged right into a stage box. It also has mirrored TRS +4 outs on the back that I feed to a line mixer for the drummers headphones. I know in the picture you will see I'm running Abelton Live, but DP is my main AXE. I also have DP installed if I want to switch it up. I really liked using Abelton because its so easy for the band to change tempos on the fly. The drummer mixes his own headphones and fires the songs from the ipad. I'm running about 12 stereo stems, 6 channels to FOH and 2 channels for headphones. If for any reason the first laptop or ultralite glitches or stops, the radial automatically switches to the B system. The show must go on! I keep the 2 laptops in sync by spitting the MIDI from the ipad/touchosc using a iConnectivity MIDI2+. They have no shared clock or sync, they just start at exactly the same time. I got all this gear except for the laptops on craiglist too ☺.

[James Steele]

Wow... thanks for sharing. I made a custom interface using a special app and drummer can pull up any song from iPad controlling Mac wirelessly. I can do the same via my MIDI Raider foot controller.

I *wish* I could afford another laptop and the full redundancy situation like that, but I'm afraid I can't. I know that's living dangerously. I'll have to study this more closely. Thanks for sharing!!!

My main concern is what was brought up earlier: if I run a TRS male -> XLR male snake from the TRS outputs of an Ultralite Mk3 to the junction box of the FOH snake and the FOH guy accidentally sends phantom power to the outputs of my Ultralite Mk 3... will it damage it? Or do I have to put passive direct boxes for each TRS output on the Ultralite Mk 3?

I'M SORRY... I missed what you said about the Radial unit. I will have to look that up!

Sigh... confused.... Again... that's a beautiful rig. I wish I had the budget for it. For starters, it'll just be small clubs, but I would love to be able to do full redundancy like that. I'm also using computer to change patches on my guitar rig. I think though I'll stick with DP for now... I don't know that I have the time available to learn live.

[dbawmp]

I wish I new more about the phantom power issue. I always figured there was some sort of protection from this in most gear but I have to admit I'm a noob with it comes to the live environment. Every time I've given a live sound guy my 1/4 line level outs I go thru DI's. Not really for the phantom power issue, but because it's a long cable run. Going thru a DI's makes it easier to run long distances. When I saw your original post I immediately thought of the Radial switcher. It may be overkill if you are not planning to be redundant and there are better/cheaper solutions out there for sure. Now that I have one, I'm gonna use it every time I'm in a live venue even if I'm not running a redundant system. You can sometimes find the mk1 used for about $600. Just a thought ☺ All this stuff is fresh on my mind right now. I will ask around to see what I can find out. The rig I built is taking it's maiden voyage this Friday. I hope I don't look like an ass!

[James Steele]

I wish I new more about the phantom power issue. I always figured there was some sort of protection from this in most gear but I have to admit I'm a noob with it comes to the live environment. Every time I've given a live sound guy my 1/4 line level outs I go thru DI's. Not really for the phantom power issue, but because it's a long cable run. Going thru a DI's makes it easier to run long distances.

Ahhh cool. Well I saw a rig someone built and they simply used a snake that was TRS male that plugged into the back of the Ultralite and then was XLR male at the other end so it could plug into the junction box of the house snake. Usually there's a box dropped close by so I figured at 20-25ft snake should reach it. It's line level, but it's balanced so it should be fine. The big concern I had that someone raised in this topic is if the FOH turns on phantom power, will it fry the Ultralite? Like I think you mentioned, the clubs I've been to, I don't see many condenser mics on stage. I suppose the drum overheads would be the exception but it's dynamics otherwise.

Good luck on the maiden voyage Friday!!

[Shooshie]

That Radial unit makes it a sweet stack. Other than that, not much has changed since I was doing this on tours. The only advice I can give is to befriend Murphy. If he decides to make an appearance, introduce him to the audience. Crack a few jokes. (Work out a routine if you're not Robin Williams [rip]) In all the years that I toured, Murphy stayed in the Green Room and never bothered us on stage. Hey, it's MOTU! I saw lighting board failures, power failures, director failures, and all kinds of things that make live performance so great to talk about around a table with other directors, over beer or Jack Daniels, but my MOTU stuff never failed. Never. Still, my philosophy then is the same as my advice now: it's tech. People understand that tech is tricky and sometimes fails. Make them enjoy it. Befriend Murphy, but then lock him in the Green Room. If he gets out, it's not the end of the world. It's bonding with the audience.

Shooshie

[HCMarkus]

A call to MOTU could probably get you a solid answer on the phantom power issue, James.

[daniel.sneed]

James I go on with the risk of 48V on your Ultralite.
Yes I still believe, it might damage your rig in some circumstances.

In real touring world, I think the best affordable solution is to get good passive DI-boxes on each channel.
They will provide:
- total protection against 48V
- total ground loop immunity (thru ground lift buttons whenever needed)
- good level match between Ultralight line output level and mixer mic input level
- no question asked, nor long talking, with sound guy

I use Radial PROD2, stereo passive DI-box (mono one is PROD). Not cheap, nor high-class budget, but good sounding and extremely reliable.

BTW, Ultralight outputs are *balanced floating* type. That is to say you may connect from Ultralight to dbi-boxes with single ended TRS.

BTW, I don't have a total backup with second computer, but I always create a clone HD a few days before gigs, with Carbon Copy Cloner.
It might save the gig, thru booting from the extern HD, in case of:
- internal HD failure (happened once in rehearsal!)
- user (me) error screwing the setup just before the gig (no, I swear, I will not!)

[Shooshie]

Balanced outputs with TRS and/or XLR plugs should not be harmed by 48v phantom power. It's the way it is distributed that makes it "phantom" and which balances it so that no lead can send that power to sensitive electronics. Positive and negative leads BOTH carry the same voltage and polarity, making it impossible for it to complete a circuit between those two leads. The return is in the ground. Or something like that. I think if you looked it up that's what you'd find.

[daniel.sneed]

Sorry to disagree, Shooshie.
AFAIK:
- pin 2 (hot) and pin 3 (cold) are set to +48V, thru a pair of 6,8k Ohms resistors, or thru a center pad of an input transformer
- pin 1 is 0V reference and ground

So, inserting a single ended (mono) TRS in Ultralight (or any kind of xlr-singleTRS adaptor), will short pin 1 and pin 2, resulting in 48V between hot and cold points of Ultralight input. Which, I think, you may not want.
Using double ended (stereo) TRS will not. But keep in mind that any jumping, or pulling out, the TRS may achieve what is stated above, during a short gap time. I wish this never happens, but Murphy states otherwise...

As HCMarkus said, a call to Motu seems a good idea.
Worth the talking time, and worth the DI-boxes cost, too.
And, of course, report here much appreciated.

[waxman]

I am using the 32 Presonus Studiolive Series III for playback of stems and mixing bands. The routing, presets, fat channel, automation, recall, monitoring and ease of use is the best I've seen yet. The onboard 32 ch USB interface makes it really a 76 channel console. Layers and User mode are well engineered. The Studiolive 16 would be fine for most gigs. If they make a smaller 8 channel that should reduce the price significantly and be plenty sufficient for most bands using tracks for playing live. Probably be some alternatives from other companies coming soon.

The guys in this video are pretty funny but it's worth watching... https://www.presonus.com/products/Studi ... 3RiX1MCmiM

https://www.presonus.com/products/StudioLive-16

[Shooshie]

Sorry to disagree, Shooshie.
AFAIK:
- pin 2 (hot) and pin 3 (cold) are set to +48V, thru a pair of 6,8k Ohms resistors, or thru a center pad of an input transformer
- pin 1 is 0V reference and ground

So, inserting a single ended (mono) TRS in Ultralight (or any kind of xlr-singleTRS adaptor), will short pin 1 and pin 2, resulting in 48V between hot and cold points of Ultralight input. Which, I think, you may not want.
Using double ended (stereo) TRS will not. But keep in mind that any jumping, or pulling out, the TRS may achieve what is stated above, during a short gap time. I wish this never happens, but Murphy states otherwise...

Yeah, you got me on that one. I didn't think of sticking a TS plug into a TRS hole. For that matter, I didn't think of plugging anything into a hot socket. Turning on the 48v is the last thing I do, after mics are set and everything. But that's the Murphy you're talking about, so you're definitely right on that. It may be ok to hot-plug an XLR, because it won't short itself. But TRS plugs can't be trusted. In fact, I've bought commercial TRS plugs and adaptors that were horrifically mis-wired. I recommend a plug tester for that. I have a good one that will tell you exactly what every pin is doing, and to what other pins every pin is connected, in a matrix of lights. Highly recommended, because of what Daniel just outlined.

Shooshie

[James Steele]

I really had no intention of plugging a TS plug into the back of the Ultralite. Why would I when it's balanced? I was planning to get a snake with 1/4" TRS on one end and keep it plugged into back of UL, and on the other end have XLR male to connect up to the junction box of the house snake that's usually dropped at the stage. It sounds like the only risk here would be plugging in the TRS to the UL while there was 48v Phantom power on the line. I plan to keep the snake coiled up in the case always plugged in. But even if I didn't, as long as you always plugged the snake in to the UL first you'd be fine. It sounds like there's no way to momentarily cause a short when plugging in to an XLR connection, right? Seems like the risk is minimal. On the other hand, I suppose maybe the ground lift possibilities of a direct box might be useful. I'm trying to not break the (aka MY) bank here.

[Shooshie]

Yeah, I think that's reasonable. Worst case scenario, buy a pin tester, keep test cables on hand, and check unknown sources for mixed pins. That should do it. The pin tester should have some kind of matrix of lights to show which pins are connected to which pins, and which way the current is going. (that's a product of which pins are shown as the starting pins, vs which ones are the connected pins.)

But we're talking about what is probably a rare occurrence, anyway. I think if you do what you said, you'll be fine.

Shooshie

[James Steele]

Well, today I finally got a TRS -> XLR snake to try this out with and I think maybe I goofed. OMG, the output level from the Ultralite Mk3 is off the chart. Maybe it's just -4db... maybe it's higher, but there's no setting in it to set the outputs to -10db, so I have a ridiculously hot signal at the XLR and when I plug it into the rehearsal room PA, even with the pad engaged, the clip warning light is showing clipping (at least it's not solid) and I barely have to turn the pot up for volume.

I'm inclined to believe I screwed up and have to return this snake and go with multiple direct boxes in the rack and let whatever sound guy I encounter take a signal out of that. Frustrated because I feel I've just taken one step forward, two steps backward.