Just a little guitar amp DIY...

I pieced this together on my coffee breaks over the course of several weeks, using surplus parts I had laying around.

Photo Album

damn, did my little amp inspire you?

thats awesome!

dave

how does it sound?

wow, that's one of my many goals, eventually, you know, that and world peace. probably before world peace.

Really Cool NYD!

Curious what it sounds like...

I really want to build a Supro... Just trying to find schematics

Sorry if I'm asking something stupid, but which tubes ?

And that's a nice-looking amp.

This looks so cool!!!! :thumb: :thumb: :thumb:

Hey Fabio, Hows it going man.. Your site back in action???

Sorry guys didn't mean to hijack..

Really nice amp NYD!

Don't want to hijack either, but what's the strip with all those jacksockets on pic #2 ?

very nice!
a friend of mine asked me about building a small amp. would you mind sharing the schematics?

nice! small amps = BIG sound. what kinda speaker are you thinking about using?

Very tasty Dave... :thumb:

[quote author="cannikin"]I really want to build a Supro... Just trying to find schematics[/quote]

"The Tube Amp Book" contains several.

Peace,
Paul

Update: I've added a schematic to the photo album.

thanks a lot!

Arrgh! I made a stupid drafting error that I didn't catch until now, even though I looked over the schematic several times before posting it. R24 should ONLY be in series with D5 and D6, not in series with the entire heater circuit. I've corrected the schematic and reposted it in the photo album. To the handful of people who downloaded it prior to this message, please delete it and download again.

Nice, I have been putzing about with a 2 watt amp of my own built around a 6S4 triode, but I have not been able to settle on a preamp or tone controls yet. I think I might give your amp a try, I think I have all the parts needed. I need something quieter and it is going to be awhile before I settle on the preamp of my own.

adam

Nice little bugger, Dave! Thanks for the schemo. Any hints about the range of tones this thing makes? Looks like a Marshall tone stack, but the rest of the pre looks more Fendery (bypassed cathodes). But those big grid resistors make me think you're expecting some serious grind. Interesting "presence" control, too.

A P

Actually, that's a Fender 5F6-A tone stack. Marshall just copied it in their earliest amplifiers, adjusting the values slightly in later models.

Yes, as you guessed from the grid stoppers, I like to crank it up. With humbuckers, you can definitely enter into "Iommi territory" with this amp. But it has a good clean tone, too--and unlike many small single-ended amps, it actually gives a usable range of clean before you get into the different shades of distortion. I attribute this to the use of a neg. feedback loop around the output section. The feedback also makes the presence control possible.

I was after something that would give a little more flexibility for playing rock (or other styles) than the usual two-knob, no-feedback single-ended grunge machine that's marketed toward the bedroom bluesman market :wink:

I'd love to post a couple of sound samples, but I live in an apartment and I can't really crank it up here (which makes my comment about "bedroom bluesmen" slightly ironic now that I think about it :wink. Even a mere two watts can be pretty damn loud through your typical highly-efficient guitar speaker. Since I brought the amp home, I've been jammin' through an attenuator.

The first Marshall amps where pretty close to exact copies of the 5F6-A bassman. They just used EL34s in the output stage and made a few very minor changes to the preamp. I have been rebuilding a bandmaster head that someone tried to turn into one of these Marshalls. It took me awhile to relise what they were doing. Could not figure out why someone would clone a bassman almost exact and then go and change the output tubes to EL34s.

adam

I just wanted to follow up with this: I took the amp over to Ytrehalf's place over the weekend and was delighted to find that, even at only a couple of watts, it can hang with live drums... at least when it's plugged into a 4 x 12! :grin:

Through the Vintage 30s, I noticed a bit of raunchiness around 3kHz that I didn't hear at home through an Eminence alnico 10", but I suppose that could be due in part to the well-known Celestion high-mid bump. There was also quite a bit more bass through the 4X12, as you'd expect, even with the control all the way down. I'd probably make some tweaks to this circuit if I were going to be playing through that particular cabinet on a regular basis.