4 Track Output Distortion

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mcpf66

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Hi,

I was wondering if any experts here could help me out with a problem

I recently purchased a 4 track, 1/4" Otari (MX5050) and discovered that the XLR outs on the back of the machine are loaded with a terrible distortion. Is this most likely an alignment problem (i have not yet aligned the machine since buying it, but i was told it's been kept in great shape and used very little) or something else? The only thing i know is that it is not being distorted when the sound goes to track because the signal coming back through the headphone mix is crystal clear; it is solely on the XLR outs which I definitely need to put the tracks on a digital medium.

any help/suggestions are greatly appreciated
 
mcpf66 said:
The only thing i know is that it is not being distorted when the sound goes to track because the signal coming back through the headphone mix is crystal clear.
Click to expand...

You'll have to explain:

signal coming back - coming back from where?

through the headphone mix - Do you mean headphones , plugged to ???? where?

I'm sure guys here can try to figure something out...
It would be the best if you describe exactly your setup/connections ... what do you record, from where, what do listen/monitor. Also what tape do you use (this may give some ideas).
In genearl: are the heads clean and demagnetized? - two basic things first.

What do you mean by "terrible distortion" ... if you can describe it.

/respects
 
the signal i'm referring to is the one that i hear through headphones coming from the headphone jack on the unit. i am making an assumption by saying that the printed-to-tape sound is not distorted because if it was, i would hear it through the headphone jack. instead, i only hear it through the XLR outputs.

by terrible distortion, i suppose i may have exaggerated a touch. but, the sound of each track sounds like it is being played through a distortion pedal...basically, it is unusable and i just need the good old clean signal

the tape is 456 quantegy

i mainly record rock sort of stuff, although the test i did was just guitars and keyboards. i may run through a couple of mic pres first, then into the Otari, then IDEALLY would take the XLR outs into the balanced/unbalanced analog ins on the back of my MOTU828mkII

hopefully this helps a little
 
oh, and like i said, i just purchased the unit and have not yet done any proper alignment (still need to get an MRL tape) or head demagnetization. but my question is based around these remedies actually fixing my problem if the sound is printing to tape un-distorted and the signal is only distorted coming out of the XLR outputs (hence, is the real issue some electronical breakdown inside of the machine that i will need to take to a repair shop to be fixed)
 
dunno why your outputs would be distorting really. i think it must be your outs busted. do all tracks sound the same? could be you playback set real hot i suppose. never had anything like that happen with my deck.
 
ok, well, this 'sonds' like your machine maybe just fine....
what do you connect outputs with? What cables do you use? Sending outs to ins of what? Mixer? amp? what kind?
 
i use standard xlr cables, all of fine quality

like i said, i take the outputs of the machine to balanced/unbalanced analog ins (1/4" - i have converters...but i know the converters are not causing the problem as i've tested them) on the back of my MOTU828mkII. no mixers/amps in the signal chain. just straight from the outs of the Otari to the Motu828.

but does this seem like a problem that is not caused by alignment/cleaning issues?
 
here's my quick guess. Also I never had MOTU interface muself...so can't be specific there at all.... but one thing to check out. How do you set/or switch between +4/-10 of the inputs on it. It maybe has to be done via software... or maybe you can do it on the interface .... maybe not. What do you know. Do you have manual for your MOTU interface. My guess is that inputs on your MOTU are set for -10. Or am I completely off track here :D ???? :confused:

some experts on Otari and MOTU ... jump in here NOW! :p
 
Check your levels - the 828 can be set to either -10 or +4, it should be set to +4 for this application.

Also I remember seeing other threads here pointing out that some the Otaris XLRs wired differently. If you still have issues with the Motu set to +4 then try swapping pins 2 and 3.
 
excellent, i'll give that a try, thanks so much guys...i'll letyou know how it turns out
 
What do the meters on the motu say. Are you peaking them?
 
no, they were definitely not peaking. the signal level was fine...just all distorted
 
make sure the "SRL" button is not pressed on the otari.

does it distort when you lower the output on the otari close to zero? I guess what I am saying is if its not a level problem going into the motu, and your cables are good, then it is probably a problem with the outputs.
 
there is no SRL button on this otari, and sadly, there is no level knob for the outs on the machine either (i suppose this machine was not one of their "top of the line" models)...the only level knobs are for the input levels.
 
Do you have an alternate source other then your computer/digital set up to test the outputs of the Otari?

If you have a regular stereo system of some kind, you could at least test two channels at a time of the Otari by using an XLR to RCA connection cable or appropriate connector and being mindful of your recording levels on the Otari when recording in the first place on it. Keep in mind your recording levels with out noise reduction should be peaking at no more the +3db on the vu meters.

If the sound is coming out clean into a regular stereo system with proper levels on the tape itself, then there might be an overload situation happening with some part of your digital/computer chain and that should be addressed separately in a different thread and in a different section of the bbs here.

If the sound is still identically distorted going into a standard stereo system with analog inputs then yes, there may be something wrong with the calibration of the deck, perhaps a bad master bias setting?

Any time problems like this arise, you MUST use a process of elimination to track down where the problem truly lays. It's not fun to do but it is necessary if you really want to fix the problem.

Cheers! :)
 
thanks to all of the replies..they have all been very useful. i have tried hooking my headphones up directly to the XLR out via a 1/4" adapter and amazingly enough, the signal appears clean. i am going to begin looking into the settings of the MOTU to see if there are some odd level settings (although i'm not sure why there would be?) is it possible that the level coming out of the XLRs is just too hot for the MOTU?
 
i'm also going to look into trying the rewired XLR cables as Arjoll suggested. there really should be no signal issue on the MOTU, and something freaky like unusually wired XLR cables would explain a lot.
 
If the levels were too hot for the MOTU, the meters on the MOTU would be pegged.
 
here's some blah I've found about motu828MkII: http://www.soundonsound.com/sos/jul04/articles/motu828mkii.htm
Again, I never had this unit, but I know in general how this type of 'interfaces' work. You really need to look into your unit's settings... whichever way it can be done (via software or maybe you can access and adjust settings from front panel of the unit, scrolling through menue/pages or what have you... you need to have manual)
One other thought, which may have nothing to do with anything in your situation, but still.... if this unit has 'internal mixing' feature and it stores (maybe automatically) settings of the 'last mix' which you've adjusted via software/or via front panel.... then you maybe have output levels very hot in your currently stored "mix settings". Again, the input levels need to be set to +4. There's Cuemix software shot at the link I've posted. Check it out too....

okey, goodluck fixin' you situation.
 
i feel totally stupid at this point, but the problem is solved. i idiotically did not bother to try using balanced 1/4" cables (possibly because i don't have any in my possession right now), and lo and behold after rigging up a bunch of wires with balanced sleeves, the signal came in beautifully

i can't thank everyone on this forum enough for helping me troubleshoot through this, i'm extremely happy right now. thanks again for all of the help!
 
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