Tascam M06 Quiet output

Discussion in 'TASCAM Analog Forum' started by Chris Welham, Jan 12, 2020.

  1. Chris Welham

    Chris Welham New Member

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    I've noticed that the R master output on my Tascam M06 is much quieter than the L output. I have only noticed this since shuffling my studio around recently. I have tried all possible combinations of channels/panning/cabling etc and as each channel (including phono inputs and heaphones) reproduces this fault my guess is that there is an issue with the master summing amp

    I have found a service supplementation manual online but no luck finding any schematics. I have opened the unit up and cannot see anything obvious, but struggling to locate where the final amp circuit is located as the board layout is quite convoluted and there are many soldered interboard wires that mean movement of the boards is quite restricted without desoldering connections. As it is a recent fault after moving, I thought it may be a loose connection, so reseated all connectors but still no dice

    I notice that a lot of the op amps are M5218Ls - would it possibly be a case of locating the final op amp and replacing this?

    Chris
  2. Chris Welham

    Chris Welham New Member

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    Okay just noticed that having nothing plugged into the R PGM out of the mixer means that the R channel picks up to normal level... very confused
    -mjk- likes this.
  3. SkywaveTDR

    SkywaveTDR Active Member

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    OP Amps do not have gain problems like this you are looking for a bad solder joint or a fader that is not the same value as the one next to it. maybe dirt. I would have to look at the unit in more detail to know where to go on that. This sound like a load problem to the output.
  4. -mjk-

    -mjk- Moderator Staff Member

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    I would swap L and R with whatever you have plugged into the PGM jacks and see if the problem moves. If so, something is loading it down.
    snafu likes this.
  5. SkywaveTDR

    SkywaveTDR Active Member

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    Yes this is some of everyday troubleshooting and a good thing to try.
    -mjk- likes this.