help puhlease!! Sontec MES 432 C/9

Discussion in 'DIY Pro Audio Forum' started by solaraeus, Dec 10, 2003.

  1. solaraeus

    solaraeus Guest

    I am in desperate need of information on how to find schematics for this EQ or someone who has parts or knows how to repair these units. There appears to be no hope for getting in touch with the manufacturer, I have tried the all of the available contact info I have as well as what I found online (which was the same) without success. I have found schematics for a version of the main PCB, but it is the daughter op-amp board that appears to be the problem. These are very expensive paper weights at the moment. Help me, help me. You're my only hope!
  2. gyraf

    gyraf Guest

    Sontec are not exactly known for handing out schematics. Is it for a repair job? The discrete opamps are known to be unstable and unrepairable. If this is the problem, order a new opamp (and a spare one if you can afford it..) from the company.

    On my page I have the 430C, maybe that helps?

    Jakob E.
  3. Guest

    Hmmm Sontec is sadly not... as the original poster found out... eazy to get in contact with.

    This is a very common problem know to a lot of engineers around the fact I would belive that it would be a lot eazier to find another used Sonteceq on Ebay or something...!!! than get in tuch with the company..!!!

    Kind regards

  4. Steffen

    Steffen Guest

    is one filterband not working? are the filter opamps discrete or IC like the MEP 250?

  5. solaraeus

    solaraeus Guest

    first of all thank you for the replies. Yes i do have the schematic to the 430C from your website, thank you but it doesn't include information about the discrete op-amps. I have repeatedly tried to contact the company and recieved no reply as of yet. The problem specifically is that the right channel has a DC offset when it is bypassed. Upon closer examination the op-ap board is discolored and appears to be burnt out. The components on that side are very hot to the touch (compared to othe other channel) and unfortunately the markings on the components have been sanded off as well.
  6. hodad

    hodad Guest

    What's the part # on the opamp?
  7. gyraf

    gyraf Guest

    George Massenburg mailed me (!) and told me, that the GML opamps will NOT work in the Sontecs (as I suggested earlier on my page).

    The Sontecs are based on the GM's, but they're not compatible.

    Jakob E.
  8. solaraeus

    solaraeus Guest

    The numbers that are on the op-amp card are an inscription that i believe is a number refering to the production serial number and then on the solder-side is the number 31-080D, traced on the board. If the components on the schematic from are the same version as ours it says the op-amp number is HS-2030. The Audio Board on the the Gyraf schematics matches ours (SPN 1110-0945-00), but i am unsure if the revision number is the same, as there does not appear to be a Rev # on our Audio Board.