Amp advice - I'll build for a friend

[fabiomayo]

Hi, guys.

I want to build an amp for a friend. I'll use a 2x12" combo cabinet and
50w (2xEL34 or 2x6L6) trannies as a building foundation. The PT is
locally made, the OT is Allen Amps TO-60

What can I build that'll offer a good basic clean tone and some marshally
crunch (ACDC rhythm style)?

I realize it's a tall order but I'm really a novice to this kind of amp and
wanted to please my good friend.

[AdrianJ]

Well, my suggestion would be a Marchall JTM45 type amp. There are a few kits available and they all look fairly simple (as amps go!!).

I'm a novice at this myself and am planning my first amp build which is going to be a Fender 5E7 type circuit, yet to decide what speaker config to go with - tempted to build the amp in a head and then get both a 3x10" and 2x12" cab built for it - fender tweed stack!!

If that goes well then I'm gonna throw myself in at the deep end with a D-type amp!! (If not then I'll get someone to build the d-type...might do that anyway cos I'm impatient!!)

You're onto a great community here though and there's some extremely knowledgable people here.

[fabiomayo]

Thanks for your reply. I figured the JTM45 could fit the bill. But how's the
clean tone? It's important to have the ability of really clean, funk grooves.

I was gravitating between a Marshally design or Fender with extra features
for overdrive (maybe a second preamp, Marshall).

I already built a couple of amps for myself but was never interested in
that kind of tone. I've built a Champ and an ODS.

[AdrianJ]

Well I've never played a proper JTM45 myself, but they're supposed to have the best clean tone out of any Marshall. Don't forget they are basically Jim Marshall's take on the Fender Bassman.

[Phil_S]

I figured the JTM45 could fit the bill. But how's the
clean tone?

The one I built uses iron recycled from an Arkay FL-30 that ran a pair of EL34's. It is a loud amp and there is quite a bit of decent clean tone on the amp. I think, as long as you get a decent OT for it, you will be able to milk it for all the clean you want. If you need a bit of grind at lower volume, a pedal will get you there in a hurry. When you crank it up, it will give you that Brit-flavoured dirt that Marshall is famous for. IMO, if you can manage the loud part, this is a great amp.

[jaysg]

Based on my experience with that Allen OT and a similar EMC OT, the basic 5F6-A/JTM45 design fitted with EL-34's or KT-77's will probably fit the bill. Bassman cleans aren't bad at all. Alternately, a well built Super Reverb is a heavy hitter when dimmed, so the ab763 does well too, and then you've got the pretty BF cleans.

[Lonely Raven]

AB763 is a huge hurdle for a beginner amp builder.

[jaysg]

AB763 is a huge hurdle for a beginner amp builder.

Not if you build it single channel without reverb or trem. It's pretty compact that way.

[fabiomayo]

Thanks for the tips guys.
I liked both ideas JTM45 or Super Reverb (though I won't be adding
reverb or tremolo). I guess it's up to my friend to decide.
Maybe I could build a Bassman/JTM power amp with one JTM45 preamp
channel and one blackface. Make it footswitchable, maybe put a pre-PI
master volume on the marshall side.

What do you guys think?

[jaysg]

I don't think you get much from a pre-PI master with either BF or Bassman preamps. A JCM800 2203/4 preamp variation is more or less the starting point for a master volume marshall. VVR/Power scaling would make the amp more useful.

[dave g]

Why don't you try a JTM45 with KT66s and a fender/marshall hybrid tonestack (try a stock blackface fender tonestack with .022s for both the bass and mid caps and change the mid pot to a 25k)? Go the extra mile and add VVR and I think you'd have something special