Hi all,
I've got my Tramp all put together (thanks mostly to Steven's excellent support
![thumbsup :thumbsup:](./images/smilies/thumbup.gif)
). It's my first build, and I've made a few mistakes in the process, so I would appreciate any feedback from those of you with more experience. I ended up replacing the MOSFET and its associated resistors because I fried the first one de-soldering. I was an idiot and soldered it before placing the board, so of course it didn't line up. The replacement resistors are exactly the same spec as the originals, just wire wound FYI. I should also note that I'm using a Tone Tubby Humboldt 10" 8ohm as the speaker and a JJ 6v6 as the power tube. Here are some pics:
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Before I get into the issues, here are some voltage readings (tweed/thin):
AC
Heater voltage is @ 7.0V
Power Amp
B+ is 430V. The VRM was set to 400V for all measurements
Cathode Voltage is 28.8V
Pre Amp
R8/C6 is 340V
V1 pin 1 is 173V, pin 6 is 168V. With the VRM cranked the Voltages are roughly 180V and 170V respectively.
The bias switch is set to 6v6 and the impedance selector is at 8ohms.
So the issue I'm having is with the amp's volume and gain output. All of the tone controls, as well as the push pull functions seem to work, but there just doesn't seem to be much output. With a single coil strat (volume all the way up) and everything on the amp cranked, there is no breakup and it isn't really as loud as I would expect. It also sounds uncharacteristically thin, with very little bass even from the neck pickup. With very hot humbuckers, I can get a little bit of breakup going with the volume past 8, but it sounds raspy and thin. It's pretty obvious that this is not normal, and that the amp is capable of MUCH more.
Steven suggested that this could be an issue with the tubes, so I decided to order a Tung-Sol 6L6 and 12ax7 as well as a JJ EL-34 to play around with. If anybody has any other ideas or suggestions in the meantime however, I'd love to hear them!
![Smile :)](./images/smilies/icon_smile.gif)