MOTUnation.com

Hi, I just used the 828 mk3 live, and it froze up completely on stage. All the outputs went completely off, all the LEDs froze in their positions. Luckily (I guess) there was no horrible noise, it just fell silent. You can imagine our horror when this happened at a ticketed event, 2 minutes into the first song after a month of rehearsals and a huge turnout.

Despite this disaster, i still think using the 828 live is a great idea. So I've outlined the exact setup and if anyone has any idea why this might have happened please reply. If i know why this happened, maybe i can fix it and use it again. That's a big maybe actually ...i am still in shock from it all, it was a total nightmare situation.

So here's what was going on.

INPUTS
7 Drum mics and one vocal mic into a MOTU 8Pre, connected via ADAT to the 828.
2 vocal mics into the mic preamps onboard the 828.
2 Electro-acoustic guitars through onstage amps, then the line outs went into Analog 1 & 2
Bass line out into Analog 3
Keyboard into Analog 5&6

DSP
After adding all the EQ, reverb and a tiny bit of compression on 1 vocal mic, the DSP meter was still just less than half

MIX BUSSES
All mix busses were in use.
Bus 1 - Front of house, was routed to Analog out 1&2
Bus 2 - sent to optical out A 1 & 2
Bus 3 - sent to optical out A 3 & 4
Bus 4 - sent to optical out A 5 & 6
Bus 5 - sent to optical out A 7 & 8
Bus 6 - Headphones

Opitical out A was connected to a Hear Technologies HearBack monitoring system via ADAT.

We have used this setup for hours at rehearsals, while recording everything in Logic. Never had a problem.

AT THE GIG
The system ran fine for the soundcheck(we rand out 4 songs through) and the first 2 support acts at the actual event. The support used only 2 mics and one of the guitar inputs. Nothing else. I even recorded the support in Logic, and it was all going great!

Then, the full band got up and started, the the sound was terrific on and off stage. About 2 minutes in though - CRASH - everything was silent! Everything!

The 828 was still on, but all the lights were frozen in their last position. I turned everything off and back on ...and it all came back fine. We carried on and about a minute later ...crash again. We gave up and plugged everything into another mixer to finish the gig. But the sound was total rubbish.

LAPTOP
I had my Macbook connected to the 828. I had Logic open and was planning to record the gig too. But i hadn't pressed record when this happened. My Mac hadn't crashed. I have a 10 mtr firewire cable, which i was using to mix the FOH sound from out front, then i moved my mac on stage as i was playing too.

DIFFERENCES
The only differences between all our rehearsals where this system ran fine and the gig are ...


The 828 was in a 4U 'soft' rack case. This is a metal rack case covered in fabric. The 4U case was full (828, 8pre, Hearcack, Headphone Amp).
We turned the stage lights on for the gig (but also for the support, no problem there).
It seemed to happen when we all played, but again, we have rehearsed like this for hours and the soundcheck was ok.

We rehearse with only monitors, so Bus 1 was not used at all (FOH mix).

Any thoughts??? Was it all my fault?? Did i overload something? Nothing was peaking close to 0db. Did it overheat?? Was there something wrong with the power?? Nothing seems that likely. Should i send it back to MOTU?? If you think you have any idea what might have happened please reply.

Thank you!
Shane

I'm doing shows with a 896mk3, tot. 24 ch, 24tr recording with AudioDesk, AULab for conv. reverb and delay,
at 192 buffer setting, WLan for remote control - laptop on stage, playing iTunes, *at the same time*
all on a Mac mini Intel. 10.4.11, with a 15 " serial touchscreen via an Keyspan serial to USB adapter.
Since 3 months now and no problem.
Nevertheless I'll consider a 2nd 896mk3...
Please report your fix, so I can sleep better again

Best

Klaus

mine has twice done this thing when i powered it up where theres a bad noise. not so much a screech but a mid toned loud drone. i turned it off then back on and it fixed both times. one clue is that while i was powering it up, my mac was also powering up and so was an ext. firewire drive. usually i power up my rack with the 828mk3 first then the rest. maybe your power up sequence could have made it happen? sorry for a weak response by not addressing your huge list of info but im too novice to know what most of it means.

good luck

when in doubt, blame the warm up band for any issues j/k

Well, that for sure totally sucks, sorry you had to endure that with an audience...

Don't have any similiar experience, but one thing stands out as a possible suspect:

...I have a 10 mtr firewire cable...

That's pretty long, especially since you had an 8 pre daisy-chained as well. Had you used this long a cable for your rehearsals? Plus, if you had your laptop out in the audience, is it possible someone had stepped on it (the cable, not the laptop ?) This would be my first item to check. Overheating would be my second suspect since you had it in a soft rack with some other gear. DSP definitely generates some heat, so maybe you were cooking it. Just guesses. Let us know if you figure it out.

If it's anything like the 828MKII, it's been my experience that low voltage is the cause. If you don't have regulated power (and I'm not talking surge strip), a full stage setup with lights can be pretty demanding. Try putting one of the "through battery" UPS devices or something with voltage regulation on the power that feeds that rack.

Thanks for all your replies (and your sympathy! - i still can't believe it happened on stage :S ).

I had thought of the firewire cable, MOTU recomend a maximum of 15 feet, which i think is about 5m. But the 828 carries on running in standalone mode if the connection to the computer dies. My mac has crashed twice before in the middle of a show and during a song. Nothing happened, this is why I was so impressed by this set up, the computer can crash and nothing happens. So i think if the firewire connection failed, nothing should have happened anyway. The 8pre wasn't daisychained via firewire either, it was in stand-alone mode as an A/D converter and connected to the 828 via ADAT lightpipe. So not even connected directly to my Mac. It's a real mystery. I've been trying to recreate the event back in my studio but can't get it to happen again. Tomorrow i have a rehearsal so we'll max out the DSP and the inputs and see if it will go again. So far tho, it's working perfectly again - but i need to trust it!

Thanks for thinking about this though - all thoughts are welcome and I'll try any ideas. I have sent the details to MOTU tech support, i'll post what they say if they get back to me. Max Temp is listed as 40C.

P.S. I just got that post from Chucks ...that's real interesting about voltage and the mk2. I didn't have a regulator, and i was in an old building. When we were setting up, some of the power points didn't work, that always worries me a bit!

Digital equipment hates low voltages. Get a Furman power conditioner and stick it in your rack, that should help a great deal.
I've been doing sound for an annual festival here in the Burg for 10-15 years. About 9 years ago we were having all sorts of dropouts, screeches and dying amps. (They had run the electric lines through the welded iron frame. Shorts and all sorts of nasties in the line.) We checked the electricity in the plugs and it was all over the scale. I finally insisted they drop a new electric line from the pole into the hall, cleaned everything up. (I still use a Furman in there though.)

Pappy

Thanks Pappy. Ok to me, it's starting to seem most likely a power issue. Will a power conditioner always ensure enough voltage reaches my gear?? I have just been looking into them and they look like they only stop voltage peaks?? And there's a real price range ..what's the difference (apart from UPS on the real expensive ones)??

Finally ..just to try and clear this up, does anyone know if the whole band starting to play through the 828 could have made the unit try to draw more voltage than was available, hence the unit seemed to crash when we all started playing? And not when just the small support band was playing, or when all the inputs were live but we hadn't started. I know a little about electronics, but not enough (is it ever enough, I just wanted to play music!).

Thanks again everyone

Most of the power conditioners out there do NOT have voltage regulation. You need to examine the specs. The ones with regulation are more expensive - I use a Furman AR1215. The less expensive way is to use a UPS unit, either a "through battery" unit (that is a UPS where the power is always delivered through the battery rather than one that switches over to the battery when a fault occurs) or something with regulation (APC units call it AVR, but I think it's just through battery). You can find the APC products anywhere that sells computers - check out the LS and RS series, the units below that don't have AVR.

Your problem is not the 828MKIII demanding/taking more power, it's everything else taking power from the line that causes the sag. The digital stuff takes the same amount of power regardless of how many inputs you are using. Whatever you end up with, just use it for the 828MKIII and 8Pre.

BTW - it's happened to a lot of us. How many motunation folks out there have blown the fuses/breakers when the band hits that first power chord and the lights come up? It certainly ruins the mood.

As people have said, it was probably power problems -- I think low voltage moments caused by lighting. You said the opening band went fine, but if there were lighting changes, the current drawn by lighting could vary a lot. If you talk to whoever was running the lighting board, they might be able to confirm if the sound went out as they were changing the lighting cue. It could also have been some other piece of equipment which draws a lot of current that turned on at those moments -- even a coffee maker could put it over the edge (it's happened...).

It's a good idea to sound check with the lighting up to reproduce power conditions of the show (unless you're familiar with the venue obviously). It's also good to plug sound and lighting into different circuits if possible, mainly to reduce potential interference but also to help prevent things like this. And, as already mentioned, using a UPS on digital equipment is also good (including lighting board; laptop battery should be good on its own). If voltage dips, that equipment will go out before amps and lighting dimmers, and if power goes out completely (breaker trips, etc.), you'll be fully back when amps and dimmers come back instead of also having digital stuff crash/freeze/needing to reboot/etc.

Igormaniac wrote:even a coffee maker could put it over the edge (it's happened...).

Hell, those damn things suck more juice than a 4000w PA system.

Pappy

Running all digital equipment from a battery thru unit is a very good idea. Lightning systems are often power hogs.
But I would recommend to make use of audio transformers to separate them from those running on regular house power.
Be cautious when touching lips to microphones too. It's been a very *shocking* experience for me when playing an electric guitar. Using a foam windscreen solved the case.

Forgot to mention: make sure to get UPS which doesn't beep or which you can turn beeping off when voltage dips -- also not good during show.

Igormaniac wrote:Forgot to mention: make sure to get UPS which doesn't beep or which you can turn beeping off when voltage dips -- also not good during show.

Good point. I have a couple of APC pieces and I had to program them using a PC and the Powerchute software via USB. Unless there's something new, that utility isn't available for the Mac. The programming sticks, so not a very big deal unless you don't have access to a PC.

Yeah, the APC shows up in a control panel soon as you plug the USB cable into a Mac.