Search results

  1. Sidewinder

    Please help! JCM 800kk arrived, and I'm 'very' under whelmed.

    I don't have a tube tester, so I don't know if any of the old tubes we're bad. I did not notice anything modded or out of order. The innards looked pristine, and untouched.
  2. Sidewinder

    Eurotubes site says 35watt dissipation for KT-88 not 25watts. What gives?

    Yes sir, sure did.
  3. Sidewinder

    Please help! JCM 800kk arrived, and I'm 'very' under whelmed.

    UPDATE: Hey everyone. I put a whole new set of JJs in the amp and set the bias at 37.2. While it does sound better, there is still something very wrong. The only way I can get close to good Marshall sound is on the beast mode with the preamp and master almost dimmed. Just playing it normal...
  4. Sidewinder

    Eurotubes site says 35watt dissipation for KT-88 not 25watts. What gives?

    Well dang guys, I was excited at first because the amp does sound a lot better, but I've had time to really scrutinize it now, and I have to say while it does sound a lot better, there is still something wrong. What, I don't know. When I started this thread, I should have told you the whole...
  5. Sidewinder

    Valvestate 232s buzz

    I'm no amp tech, but for what it's worth, have you ever changed out the preamp tube? If not, maybe it's finally wearing out after 10 years of use. I've had similar sounds by having a bad guitar cable. Maybe the tube socket is dirty also. There is a section of the forum called the...
  6. Sidewinder

    Eurotubes site says 35watt dissipation for KT-88 not 25watts. What gives?

    Well the amp sounds 'way' better than before, and sounds really good to my ears. I'm very pleased over all. I may keep the bias setting where it is for a bit, but I think I may like it a bit hotter; say up to 38. I want to play it enough before I tweak it higher so I'll have a solid grasp on...
  7. Sidewinder

    Eurotubes site says 35watt dissipation for KT-88 not 25watts. What gives?

    DING DING DING! We have a winner! When biasing the JCM 800KK the probes have to be on the two center tubes. Now the adjustors are adjusting as would be expected! I have the two sides dialed in at 37.2 mA. I'm going to check it again in 15 minutes to see if it holds. I'm so happy right now...
  8. Sidewinder

    Eurotubes site says 35watt dissipation for KT-88 not 25watts. What gives?

    Here is where I got the idea to remove the tubes to check plate voltage. See second post. :wow: http://www.marshallforum.com/marshall-amps/19826-checking-plate-voltage.html
  9. Sidewinder

    Eurotubes site says 35watt dissipation for KT-88 not 25watts. What gives?

    I now have the two bias probes placed on the middle two tubes, and she's warming up. Hopefully my theory about where the pairs are placed is correct. Any thoughts on this Martystrat54? Do you think I'm headed in the right direction? I guess I'll know soon enough. I have to say I'm have an...
  10. Sidewinder

    Eurotubes site says 35watt dissipation for KT-88 not 25watts. What gives?

    Photos: Notice the configuration relationship between the tube and board. http://sidewinder.smugmug.com/Electronics/Misc/i-Ns7pnC4/0/X3/2013-03-17_19-46-31_447-X3.jpg It must be paired the way I'm suggesting. Just look at the layout...
  11. Sidewinder

    Eurotubes site says 35watt dissipation for KT-88 not 25watts. What gives?

    In other words bias pot 1 adjust position 1 and 2 and pot 2 adjusting position 3 and 4 as opposed to the standard JCM 800 positions IE 1&4 and 2&3?
  12. Sidewinder

    Eurotubes site says 35watt dissipation for KT-88 not 25watts. What gives?

    4 Brand new matched JJs from The tube store. They all said 44 on the tube boxes. I took it, that indicates matched, as I ordered them. Do you think maybe the problem is the tube positions on the board are paired differently as mentioned above. Also thank you for all the help here!
  13. Sidewinder

    Eurotubes site says 35watt dissipation for KT-88 not 25watts. What gives?

    25/470x70 37.2 bias is what I'm getting. I'm starting the think one of the bias probes might be located incorrectly. I was told in my other thread to locate them side by side and to one side because the two outside tubes are paired together and the two inside tubes are paired together. My...
  14. Sidewinder

    Eurotubes site says 35watt dissipation for KT-88 not 25watts. What gives?

    Okay, tubes are in, warmed up. Pin 3 @ V101 tube is 470vdc pin4 @ v101 tube is 466vdc Pin 3 @ v102 tube is 470vdc pin4 @ v102 tube is 461vdc I'm running a digital bias probe. I checked bias just to see where they were with the new tubes @ the old bias setting. V102 was way high 67 and...
  15. Sidewinder

    Eurotubes site says 35watt dissipation for KT-88 not 25watts. What gives?

    Thanks! Ya, I can Dig lol! This is why I'm asking, I want to be sure at what I'm doing. I read in a different thread at this forum today that for the most accurate plate voltage measurement, one should pull all power tubes and measure at pin 3 with power and standby on. I'm not clear if...
  16. Sidewinder

    Eurotubes site says 35watt dissipation for KT-88 not 25watts. What gives?

    With the tubes out at pin 3 I'm getting 513 VDC. With 25watt dissipation: 25/513x700(70%) = 34.1 for bias setting. With 35 watt dissipation: 35/513x700(70%) = 47.7 for bias setting. I measured plate voltage with tubes out, black to chassis, but I stuck the red into the topside pin 3...
  17. Sidewinder

    Eurotubes site says 35watt dissipation for KT-88 not 25watts. What gives?

    The title say it all. In the thread I started on biasing my JCM 800 2203kk members are giving me formulas saying to figure 25 watts for dissipation. I just stumbled onto a different suggested dissipation for KT-88 tubes which is what the JCM800kk uses. Is it 35 watts or 25 watts? Quote...
  18. Sidewinder

    Does this look right? JCM 800kk board?

    Okay, I wont give it a second thought!:thumb:
  19. Sidewinder

    How do I learn how to tube and bias my JCM 800 2203kk?

    Thanks a lot big dooley, now I can get back to biasing!:applause:
  20. Sidewinder

    Does this look right? JCM 800kk board?

    Okay, but is it okay that the wires are touching?

Latest posts



Top