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  1. VanR

    This OT with what tubes?

    How high is the B+? JJ 6V6S's will take like 500 volts. I used to use them instead of 6L6GC's in one of my Peaveys.
  2. VanR

    My plans for tonight

    Check carefully for a little whisker of solder or one tiny strand of wire touching something it shouldn't be. May have to use a magnifying glass. You did only ground one end of those shielded cables didn't you? Generally the ground for the Marshall tone stack is on the middle pot. You may have...
  3. VanR

    1983 jcm800 4210 to el34 question

    Could be, but it could also be the tubes. For instance I received a new pair of JJ EL34's from tubedepot the other day. My old tubes were biased at 30mA at 490 volts. Dropped the new tubes in at the same setting on the bias pot and they draw 11 mA. Had to adjust the bias pot upwards to get them...
  4. VanR

    Testing Turns Ratio On Output Transformer

    So this is a used PT? Then I might agree with Mickey.
  5. VanR

    Testing Turns Ratio On Output Transformer

    I'm not suggesting they be close together unless you have no choice. If you have plenty of top side chassis room put them on either side of the chassis. But you got to put them somewhere and sometimes that is closer than you would like.
  6. VanR

    Coverting a JMP 2204 or JCM 2204 to EL34's

    I agree. Just piggy-back the resistor and don't worry with all the rest. Your amp won't care.
  7. VanR

    Rated power VS. Musical power....

    Everything used to be rated in RMS, then the marketing folks got involved. They tell you the peak power and then when you burn the voice coils out they say no warranty because you over-powered them. Which you did. This is especially true in PA speakers.
  8. VanR

    Just picked up a 1966 stack, got a question

    Yep series. 16 ohms.
  9. VanR

    This OT with what tubes?

    For EL34 if you notice all the different voltages (Va) in AB1 Push/Pull and different screen voltages (Vg2), different (Z out) gives you different power outputs (Pout). Choose your plate voltage and follow the chart. Still like I said nothing is carved in stone, for instance Ken Fischer ran a...
  10. VanR

    This OT with what tubes?

    Yeah that is the OT Weber uses for their JTM45 and 50 watt 1987 Marshall. Also their Java Trainwreck Express kit.
  11. VanR

    Testing Turns Ratio On Output Transformer

    Frankly I always turn them 90 degrees and as close as they have to be. Never had any problems and I sure haven't used the headphone listening thingy either. I got better things to do. You may be thinking about this too much. Just hook it up and play and see what's what.
  12. VanR

    Testing Turns Ratio On Output Transformer

    I wouldn't worry too much about the difference in ohms measured. If it works and sounds good that is all that matters. Every OT is off some because of the way they are wound.
  13. VanR

    Testing Turns Ratio On Output Transformer

    This should be the same OT in this thread: http://www.marshallforum.com/workbench/66860-ot-what-tubes.html
  14. VanR

    This OT with what tubes?

    Fender used 6600 ohms for a pair of 6V6's in Deluxe Reverbs I believe. If you already have that OT you could always give it a try, but there are more suitable and less expensive OT's for a pair of 6V6's than that one. Go to Duncan Amps site and check out the TDSL. Just type your tube type in.
  15. VanR

    This OT with what tubes?

    A pair of 6V6's usually runs 8K (although Fender used 6.6K on some amps) so 4 6V6's should run 4K. My guess is you could use the 3.4K just fine. Primary impedences are not set in stone and you can get by with a lot of different impedences. That particular Weber OT they use for 2 6L6GC's (6800)...
  16. VanR

    Testing Turns Ratio On Output Transformer

    Output Transformers: A Discussion of Basic Principles - YouTube Start about 12 minutes in.
  17. VanR

    Newb with socket question

    But the bottom part of the metal shield is just crimped onto the socket itself. Remove it and replace it with another one. Some of them aren't even crimped they just sit atop the socket and are held to it by the two screws. https://tubedepot.com/products/miniature-shield
  18. VanR

    I finally got a new head, found out why it was so cheap!

    Perhaps in your opinion but not sonically superior. I'll never use 6L6's again.
  19. VanR

    Tube Bias Meter

    I use a $5 multimeter I bought at Harbor Freight as a dedicated bias meter (bias probe stays attached to it 24/7). Seems to work fine. I wouldn't worry too much about it. Worst thing that is likely to happen is you will blow out the fuse in the meter. I have 2 other meters of various costs for...
  20. VanR

    716P Orange Drop Polypropylene Film Capacitors for JCM 800

    I bought some generic yellow 630V caps from tubesandmore.com and those things sounded excellent in my 15 watt High Octane's. Tore out all the Orange Drops and replaced them with these.

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