Recent content by Komodo

  1. K

    Yamaha M4 level pots

    Does anyone have a source for replacement level pots for the M4? single gang 30Kohm 15mm PC mount carbon
  2. K

    ID these speakers?

    Yep, totally get it. I don’t think they’re for sale anyway, they were using them to play music on in the shop. They sounded good and I couldn’t ID them. I’m set with my KEF 104.2 currently.
  3. K

    ID these speakers?

    Interesting, you may be right. I thought the side paneling front and back was really odd, and the lack of badges on the front. Good job. That said, they did sound really good.
  4. K

    ID these speakers?

    I should’ve gave relative size since it’s hard to tell from the picture only. They were probably 20” x 30” on the front panel, and maybe 18-20” deep? Maybe somewhat smaller, kinda like a Klipsch Heresy. They had a real clear and rich sound, I actually looked up to see what they were because the...
  5. K

    ID these speakers?

    Saw and heard these at an antique mall and couldn’t get up to see any label. What are they?
  6. K

    Yamaha C2a DC offset tone control problem - one channel only

    I'm only referring to the hi def layout and my actual board. I think you found any / all errors same as me. I've been working the tone board left to right and what I'm seeing matches your conclusions: -R521 and the first R522 are correct. Measures 4.7k -R551 is correct, R522 (2nd one) should be...
  7. K

    Yamaha C2a DC offset tone control problem - one channel only

    I will Milo, and thanks for your help. Sorry didn't get back sooner, there were several other projects on my bench first, I scored another pre to hold it's place (B&K Pro-10MC), and then did a complete inventory of my C2A using the blown up print of the schematic you gave me. I didn't notice any...
  8. K

    Yamaha C2a DC offset tone control problem - one channel only

    Starting full resistor replacement of the tone board. Still wondering about those ceramic capacitors? Also wondering, why is it just the resistors on the tone board? Seems odd.
  9. K

    Yamaha C2a DC offset tone control problem - one channel only

    Back at this. Have a full resistor list made by inspection. Should I replace the tone board ceramic caps at C505/506, C511/512, C517/518, C539/540? If so whats good replacement? Values: A1000J and A150J
  10. K

    Yamaha C2a DC offset tone control problem - one channel only

    OK, I've got a list to compare to and will make my own list based on my unit. That said - the EQ idle current test points and adjust are on the main board? It seems odd that issues would show up regularly in the smaller PCB. This is frustrating as I had it in service for a year with no issue...
  11. K

    Yamaha C2a DC offset tone control problem - one channel only

    Replace every resistor in the whole unit?
  12. K

    Yamaha C2a DC offset tone control problem - one channel only

    Now I'm really confused. After reflowing some joints, I've got stable 23mV idle current in the EQ section (L) channel, but (R) channel gives me 35mV with only the TP4 + test point and as soon as the TP5 - is attached it flutters to 0mV. I've poured over it, there are no bridges or apparent...
  13. K

    Yamaha C2a DC offset tone control problem - one channel only

    Does anyone have an PDF of the service manual in color or with the parts list? Every one I find online has no parts list.
  14. K

    Yamaha C2a DC offset tone control problem - one channel only

    Thank you. My guess is that replacing all of the resistors merely gets the one or two that may be out, but it also future proofs it. In my case, I wondered if the direct correlation with the bass control would give somebody an idea of where I might be looking.
  15. K

    Yamaha C2a DC offset tone control problem - one channel only

    My C2a has been in use after a recap and fix of one transistor last year. I opened it to replace some caps I had skipped, and replace all trimmers. On adjustment, everything is great until I try to set DC offset in the tone section. Left channel is right on and stable, the Right channel is...
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