Announcement

Collapse
No announcement yet.

Circuit of the random homemade amp I ended up with

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Circuit of the random homemade amp I ended up with

    Hello knowers,

    Be gentle I'm just south of hopeless on this kind of thing, but I had an interesting amp experience recently I thought I would share. I picked up a home built amp that was thrown in as part of a guitar trade and while I think it looks seven shades of awesome, it had no head room at all. Move the volume a mm or so and boom into distortion - kind of good sounding distortion actually, but there was nothing by way of clean tone available.

    I didn't know anything about it, and the fellow I got it from seemed to know very little either. I finally had it looked at by an amp tech in Indianapolis (Uncle Albert's if you've heard of it. I hear he's slightly famous?) and he finally got it working after removing some pieces and rewiring others and now it sounds pretty nice actually. I attached the schematic that was drawn up for me by Kevin (the amp man) and it includes some notes about where he removed bits to get it working. Clearly, I know nothing about this kind of thing, but maybe these schematics make some kind of sense to someone here.

    The breakdown on the amp from what the tech told me:

    Class A
    running 2 parallel 6L6s
    single ended

    My understanding is despite the 2 25 watt 6l6 tubes I should probably expect something like 15 watts based on the design. Just wanted to pick your brains. It was certainly plenty powerful plugged into the test speakers at Uncle Albert's.

    What do you guys think? Anyone recognize this design?

    just a thought. Figured I'd try to learn something about this new toy.

    Click image for larger version

Name:	20150129_165921.jpg
Views:	1
Size:	1.72 MB
ID:	869275
    Click image for larger version

Name:	6L6Schematic.jpg
Views:	1
Size:	583.9 KB
ID:	869276

  • #2
    Cool. The knobs and power transformer look like they came from a 60's or 70's Traynor.
    WARNING! Musical Instrument amplifiers contain lethal voltages and can retain them even when unplugged. Refer service to qualified personnel.
    REMEMBER: Everybody knows that smokin' ain't allowed in school !

    Comment


    • #3
      Hi Dirk, welcome to forum !
      Schematic of your amp is similar to Fender princeton 5F2 with added tremolo.
      It looks to me amp was built to accept 6V6 and 6L6 in output. It's hard to say without measuring impedance of the output transformer if the builder intended to use both tubes simultaneously. There are different cathode resistors for output tubes (250 Ohms - for 6L6 and two 1K in parallel- for 6V6 )

      Comment


      • #4
        I built something similar but with a different pre-amp scheme.I did have a trem,originally,but removed it.That output looks like he should be using a 6v6 and 6L6 as epis pointed out,but if you have 2X 6L6's in there one is going to be biased hotter than the other.Dont know what the idea of that is.I would think you are only getting 15 watts out of a pair of 6L6's because the OT may be limiting things there? I get 25 clean watts out of mine,but the OT I have is probably twice the size of that one,much larger than my PT,which looks to be about the same size as yours.I have the power tubes sharing an adjustable 500 ohm 25watt cathode resistor.

        Comment

        Working...
        X