Am I up for a kit build?

tfarny

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I really really have a hankering to try an amp kit this summer - specifically the Allen Classic 10. It's a SE circuit, no verb or trem, volume / tone / boost switch. I think the takeoff point was a 5f2a with a SS rectifier and a 6l6 or el34.

On paper it sounds just like what I had always wanted a champ to be but wasn't - harmonic-rich breakup, with a reasonably tight bass response, at a volume loud enough to play a gig with a light-handed drummer or no drummer. I feel like the classic champ formula gives you the goods at a stupid in-between volume, too loud for when the wife is around and too quiet for a rock n roll show.

I can wire up guitars no problem, been soldering for years. I can read a wiring diagram and maybe kinda understand a schematic (it would take some googling). I can easily build my own cab too.

What I don't think I have the time and patience for is to actually understand how it all works - Long Tailed Phase Inverter, Negative Feedback, etc. you guys might as well be speaking in Klingon. I mean, at this point I know what a tube vs ss recto generally does to the sound, for instance, but the technical side of it I really am just not interested in.

Does that mean I shouldn't try it? It's $500 plus shipping, not a fortune by any means, in fact probably the cheapest giggable handwired amp around, but I don't want to be frustrated all summer with a bunch of caps and resistors all over the dining room table. What are your thoughts, oh great tdpri amp gurus?
 

Lowerleftcoast

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Once the amp is up and running, a voltage chart will be wanted. The voltages will be near 400 volts. Are you knowledgeable enough to keep from getting zapped?
 

tfarny

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Once the amp is up and running, a voltage chart will be wanted. The voltages will be near 400 volts. Are you knowledgeable enough to keep from getting zapped?

This question assumes that I will be poking around inside of a live amp with chopsticks, right? At this moment I definitely would not ready to do that - but why would I have to do that unless A) I have problems AND B) I can't take it to my local tech to fix my problems? It seems that assembly is far easier than repair. No?
 

kingofdogs1950

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I say go for it.
We are not talking rocket science.
Learn about essential safety practices.
I built an Allen 5f1+ which is similar but had a second preamp tube for another gain stage.
Allen's kits are excellent. According to his website full instructions, layout and e-mail support are included.
His instructions are quite good as is his e-mail support.

King
 

lathoto

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The 6L6 stays cleaner much longer in my 5F2A (it has a mod which allows me to switch rectifier and power tubes). My recommendation is an EVM12L. In the avatar you see a 6G15 reverb unit and a 15EVML extension cab. Good luck.
 

Lowerleftcoast

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This question assumes that I will be poking around inside of a live amp with chopsticks, right? At this moment I definitely would not ready to do that - but why would I have to do that unless A) I have problems AND B) I can't take it to my local tech to fix my problems? It seems that assembly is far easier than repair. No?
Yes you could assemble the amp. A tech could make sure the voltages and bias are in spec.

There are ways to check voltages hands free in the amp to make sure you are safe. Ime you can build and service a simple amp like this with some reading/discussion about safety. You will be learning as you build the amp. Ime you will find learning is the best part of building a project like this.

When an amp is first fired up, it is a good idea to have a light bulb limiter (LBL). In case something is mis-wired, a LBL will save the amp from blowing a fuse or possibly damaging more expensive parts in the amp. These are cheap and easy to build. TDPRI member robrob (Rob Robinette) has several amp building sites. He has a design for a LBL. He also has a lot of info about building a kit like you are contemplating. It is a valuable resource.
LBL instructions are also available on youtube.

Enjoy the experience. I expect you will be planning your next build before this one is finished.
 

screefer

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Roger on the terms. Google "phase inverters for the common man" and then let your curiousity take over. One answer begets another question. It is very edifying.
With your stated experience you're a shoe-in.
Safety first and good luck!!
 

harpdog

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Yes, do it! I was inexperienced when I built my Champ kit and it turned out nice. I felt rewarded by the experience.
I have to go back in and make some wires shorter, so I am studying procedures to discharge capacitors and stay safe.
 

Asmith

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I wouldn’t worry too much about struggling to understand how an SE amp with no frills works. You only really need to know how the power supply works, how a triode gain stage works and how a pentode/beam tetrode output stage works.

At bare minimum you should learn how to safely work with the high voltage as you’ll want to check your voltages at various points to ensure your amp is healthy once completed.

I think if you’re competent at soldering and can follow a layout/schematic there is no reason why you can’t learn how to build an amp
 

tfarny

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and how a pentode/beam tetrode output stage works.
Also how to calibrate the dylithium crystals, captain! It's when people write sentences that go "You only need to understand how tzgaitori cghtoghali g*$&(% operates, and you will be perfectly safe!" that I start to get a little squirrely.
 

dan40

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Building the kit should be no problems if you are use to soldering inside of a guitar control cavity. If the startup and testing phase make you nervous, you can always have a tech do the first power up for you.
 

ce24

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Absolutely go for it....I have a hard time with schematics but give me a layout and I'm good.....I built a 5 e3 and a vibro champ. Just with good soldering skills, and a layout and patience.... You'll dig it.
 

Asmith

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Also how to calibrate the dylithium crystals, captain! It's when people write sentences that go "You only need to understand how tzgaitori cghtoghali g*$&(% operates, and you will be perfectly safe!" that I start to get a little squirrely.

They’re just the names of the valves/tubes. A pentode is called a pentode because it has 5 terminals, a tetrode has 4. My point was that in a basic SE amp you have a lot less to worry about as there are only 2 or 3 elements of the design that will be totally foreign to you.

Maybe it’s best you read up on these parts before getting an amp kit there are plenty of great online sources such as valve wizard.
 

AlbertaGriff

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Yeah, go for it! I built an amp from a mojotone kit in 2019 and it was very satisfying. Good instructions and layouts help. Double check everything before soldering it in. Follow @robrob's website for startup (build a lightbulb limiter).
 

bryankloos

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Dave's designs, amps, and kits are solid! I have his Encore, Brown Sugar, both built from kit. I am now building a custom Camp/Reverb using his transformers. You couldn't ask for a better guy to buy from.

I'm in South West CT, and I'm guessing not to far from you. If you have any issues or need help I can lend a hand. I've got plenty of experience and the tools to help should you need, not that I would expect it as the instructions are pretty easy and thorough.

I say dive in!
 

schmee

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I can't imagine playing a Champ at a gig with any drummer at all, or a band really. A duo could work though. Maybe it's just me.
I have a Champ 12, about twice the watts of a Champ. I can barely do rehearsal with it, but can.
 




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