trinityamps.com

hi all,

Finished MY tramp build yesterday, and have been playing around with it the past day or so. The build went really nicely - I was very fortunate in that I was successful without having to troubleshoot or do any rework (this is my second full build, but I've done many rebuilds, overhauls, mods, and do repairs on vintage amps for a mom 'n pop music store in my hometown).

Anyway, the amp is quiet, powerful, and all the functionality works fine. In total, it's a nice little amp.

BUT - I'm not thrilled with the tone all that much.

My main complaint is that flabby bass. I run this guy in 'thin" mode and still have the bass control on '0', and the farty low E drives me bonkers. The amp is also, paradoxically, a bit too bright.

Now - I know where to begin to start paring out that bass, but rather than start doing a "rebuild on a new build" (essentially re-designing the preamp by trial and error, one component at a time) - I'd first like to ask if anyone has already been down this path with the amp and can fill me in on a nice quick 'n dirty way to remedy this and save me some time.

I primarily use Les Pauls and ES-3xx guitars, I'm sure I wouldn't be bothered by this if I was a single coil guy, but I'm not.

Thanks,

Fred G.

fredg said: Now - I know where to begin to start paring out that bass, but rather than start doing a "rebuild on a new build" (essentially re-designing the preamp by trial and error, one component at a time) - I'd first like to ask if anyone has already been down this path with the amp and can fill me in on a nice quick 'n dirty way to remedy this and save me some time.

You probably have read the Tone Tweaking for the Tramp section based on your comment, but you might check the Tweed Builders guide for actual values as a starting point, so that's all I can suggest FWW. Sounds like you have more "experience" than I actually do, though Hopefully someone can chime in.

_________________
"The only problem with being retired is you never get a day off"

No, I hadn't seen either of those - I'm new to this forum. Thank you for pointing me in their direction!

I definitely want to take as many shortcuts as I can. I sat down last night looking through the schematic and taking notes on what I could do to tune this circuit, but...that can be time-consuming as hell, and a tweak in one place can lead to a downstream effect, and it can get to be like playing "whack-a-mole" in some cases. I'd much rather get tips from folks who've already run the gauntlet.

Thanks Hankules!

Hankules, I searched the forum but I can't find a "tone tweaking for the Tramp" section - can you provide more detail or the link?

Thanks!

Oh, wait - you mean the section in the builder's guide?

Yes, those are pretty standard tactics and actually, the notes I wrote down last night are more detailed approaches to exactly what that section suggests.

I was hoping to find some info from someone who's already been down this path and could suggest actual component values. Changing coupling caps and fiddling with preamp cathode component values is a pretty standard approach.

I'll check out the Tweed builder's guide.

Thanks again!

Sorry , should have said Tramp Builders Guide The Tweed Guide's Tone Tweaking section gives some ideas of actual values to play with.

_________________
"The only problem with being retired is you never get a day off"

OK, I just figured I'd attack this from my own experience.

First thing I did was to jumper the feedback resistor across the volume switch. This leaves the feedback resistor in-circuit all the time, regardless of whether the "gain" knob is pulled in or out. Who would want a small amp like this, with this preamp circuit design, to not have any negative feedback, is a mystery to me. This immediately puts somewhat of a damper on the "farty" bass, but still allows the nice extra crunch to kick in when the knob is pulled for "gain"... you need some negative feedback unless you're building a Vox-style circuit, and the Tramp just is NOT that. You might want to experiment with a 15k or 18k feedback resistor instead of the 22k to tamp down on the amp a bit more. If you want wild-assed upper-mids and highs, you can rig a .1 cap in the switch to go across the feedback resistor when in "tude" mode...this'll keep the bass from running amok but still give you a "presence" control effect. I doubt anyone would need this, though - this amp isn't hurting for highs.

Second thing I did was remove R12 and just jumper across where it was. This gives a little bit more control over the tone circuit. Again, the tone stack, as designed, IMHO and to my ears, doesn't give much control over the bass spectrum. DISCLAIMER - I'm a Gibson kinda guy, Fenders will be a different animal with this amp. Still, I'd recommend these two changes for either single coils or humbuckers. It makes the amp more useful and versatile.

This amp has been radically improved by these two small changes, and now sounds more like a "big boy" amp that can be gigged with. I think I can fine-tune it a bit more, we'll see...

I'm going to experiment with tube swaps and speaker changes tomorrow when I can make more noise and not wake up the household. I think an ANOS 6L6 and ANOS 12AX7 will make a big difference. I have accumulated an excess of 12" speakers over the years, too, so I have a number of options to choose from there, as well.

I'll keep posting back, if anyone is interested. Otherwise, I just like blabbering to nobody in particular.

Please do! I'm always interested in learning, plus this virus is keeping me in. Fat, high BP and old. And need to stay engaged.

_________________
"The only problem with being retired is you never get a day off"

I can walk you through the mods I made, if you'd like to try them. Also if you want to put in a cap to switch across the feedback resistor. They aren't very intricate.