Tube Amp Info

[szulc]

For those of you who want to learn about tube amps, and don't believe that you don't need more than a watt or two to get good tone.

http://www.ax84.com/home.html

[Bongo Boy]

Ohhhhh baaaabeeeeeee!!! I can see myself digging out the old DMM and soldering pencil now. Jeeeez my wife will flippin' KILL me!

(I used to have a 1949 Collins FM receiver (with a front-panel beat freq oscillator control, big fat tubes and everything) that just about cost me our marriage.) Hmmm...now where did I put that box of Bakelite parts?

NP: Caprice No 24, Jason Becker

[Oakleaf]

how much would it cost me to build something like that?

[Bongo Boy]

My rule of thumb (after 30 years of 'building stuff') is that ANY project--doesn't matter what it is--is a $100 to get started if you have the tools already. Doesn't matter if it's a guitar amp or a pair of wooden saw-horses, it's a 100 bucks minimum :D

Now, if you don't have basic tools such as decent wire cutters, strippers, soldering gun, solder, solder sucker (mistakes), volt meter, electric drill...etc., etc., etc., then make the basic estimate $300. We're not talking the electronic parts yet--I didn't even know you could buy discrete components anymore.

Then, if you have to build a speaker cab, that's another project, so add $100. If you don't have access to woodworking tools (NOT carpentry tools) like mitre or table saws, routers etc., then add $500, conservatively. Finally, add in the speaker(s), $90 each.

My estimate, if you don't have anything around the house that looks like it to goes to a guitar amp or could be used to build one, it will cost AT LEAST as much as a Fender Blues Junior ($400), for example. Near as I can tell, it would be WAY less expensive to buy one from Doberman--that's just based on my experience which hasn't been so good with 'projects'.

I assume since you're asking the question that you're not too familiar with electronics projects. One thing most of us assume when we do them is that if we follow the circuit diagram, it will work. Consider what you'll need to do if it doesn't in the cases where a) you built it yourself and b) you bought it with a warranty.

I'm NOT endorsing Doberman--I'm just giving my opinion on electronics projects! BUT, the site has a forum section (sort of), ask the guys who've built them. Make sure to also ask them what they already had on hand--most electronics hobbyists have most of the crap they need laying around the house or can 'liberate' it from work.

Finally, I went to www.hoffmanamps.com, where the guy sells pretty much everything you might need, has a boatload of info on amps, etc. Now, he's the guy selling the stuff, and here's what he has to say:

"First of all let me start by saying, it is way more expensive to build an amp from scratch than to just go buy an amplifier."

[Bongo Boy]

Originally posted by szulc
For those of you who want to learn about tube amps, and don't believe that you don't need more than a watt or two to get good tone.

http://www.ax84.com/home.htmlThis site is also worth a look for its many links to other nifty places--lots of little amp shops, etc.

Also, if you do a web search for 'grill cloth' and 'grille cloth' you'll likely find some very cool stuff---and ideas.

[Oakleaf]

thanks for the reply. i new it'd be costly, most learning experiences are. but that's what'd i'd be doing it for. if i knew how to build one than maybe i could do tweaking and fixing to the store ones later on. ya know

[Bongo Boy]

Another thought. The folks at that site have a power supply project called the Tone Brewery. Looks like a modular concept: build one power supply use it for multiple amps. Great idea--and you probably can't buy such a thing packaged for a guitar amp.

Likewise with building a cab. Conceptually, at least, you could design a cab that is modular as well, or at least allows configuration and experimentation (closed, semi-closed, etc). "configurable" and 'rock solid" don't usually go together, though. But...I've read a number of threads by folks who pay the big $$$ for cabs they've listened to in the store only to find they don't like 'em that much. It's an idea, at least.

[Bizarro]

This could be a great project!

I did a similar project a while back and I learned quite a bit about tube circuits in the process. I recommend the RCA handbook if you can find it. There are versions online in pdf format. Google-power might be necessary to find it!

If you start working with actual circuits, be very careful because tubes use very high voltages and you can get knocked on your butt, or worse! They use big caps and those are dangerous when charged up.

Good luck, and be safe too!

p.s. If you make the next great tube amp, please give ibreathe members a discount!;)

[Bongo Boy]

This little topic is suddenly way more interesting that it was when I was dumber than I am today. :D

If you listen to some of the sound clips at the site cited :) by James above, I think you'll be impressed. After reading quite a bit of the material at that site and at www.amptone.com (as well as the links it provides), it's clear that an all-tube amp with estimated output power of ~0.5-1.0W is the [stuff].

What seems to be fairly clear is that, with 0.5-5.0W of power and a 4x12, the garage band dude has what's really needed for some serious sound ("let me up on the stand, and let me kick out the...").

Getting to the 'what does it cost' portion of the program, what isn't so funny is the absurd prices for tube amps that I have to think are grossly mismatched to actual requirements (for most folks). I was just about to spend $650 for a 15W amp, and now I'm thinking not. For $250 or so, I think I can build or buy a 1W amp that will come closer to reality.

Anyway...with beat-to-hell Fender Champs selling for $250-550 on the 'precious heirloom' market (and being useless as-is for what I want), I'm thinking this DIY, indie amp thing actually IS promising. Anyone here built a microamp like this?

[Bongo Boy]

Originally posted by Bizarro
If you start working with actual circuits, be very careful because tubes use very high voltages and you can get knocked on your butt, or worse!Yeah yeah...voltage, schmoltage! It's the amps that REALLY hurt!!

We used to go down to the electric fence and see who could hang on the longest, just for fun!! No guts, no glory! Ya wanna build an all-valve screamer or not?

Uh..come to think of it, maybe that's why I can never remember what I did yesterday. Ya think?

[EricV]

LOL...

Yeah, back when we had nothing, we used to do that too. Remember ? Every morning we had to walk to school, 7 miles one way, 9 the other, through 12 feet of snow...
Eric

[Bongo Boy]

Hah!! Only 12 feet, eh?

[EricV]

Well, back then we were only 3 feet tall !
We had nothing, not even size !

Remember those days ?
Eric

[Bongo Boy]

Sure. I'll tell ya what, back when I got into computers, we didn't have any ones like these kids nowadays--all we had to work with were zeroes.

[Bizarro]

We used to go down to the electric fence and see who could hang on the longest, just for fun!! No guts, no glory! Ya wanna build an all-valve screamer or not?

Hmmmm... we used to pee on them electric fences, just for "fun" I'm not sure you can, or should, top that!;)

[Bongo Boy]

Originally posted by Oakleaf
how much would it cost me to build something like that? The no-kidding answer (finally) is about $250 or so for the complete kits (chassis, no housing). There is a link at the ax84 site for 'boutique low-power amps', and the Allen "Class Act" amp, which is an absolutely beautiful piece of work, sells for $699 in kit form, and can be set up to run at about 3W. That's a mere $230 per watt :D (www.allenamps.com).

I didn't realize it until now, but the Univalve can be set up to run at about 3W also using a 6V6 or the THD Yellow Jacket tube.

If you'd prefer to spend much, much more AND have a conversation piece for the coffee table, please look at this little work of art:

http://www.vintone.com/clipper.html

[Bongo Boy]

Referencing the Vintone "Clipper" noted above: the marketing spiel refers to "overbuilt" components such as power transformer, "excessive" DC filtering and point-to-point wiring. While these may sound like wonderful things...explore the internet for other opinions--there are other expert designers out there whose opinions will differ on the benefits of filtering.

I just bust a gut when I see "point-to-point wiring" listed as a "feature" (and none of those nasty 'tag-boards'!). Uh huh, you betcha.

This is like advertising that your software "utilizes genuine monolithic code with extensive GOTO structures" with none of those nasty "modular subroutines" that get in the way of efficient debugging. :)

Any builders here at iBreathe? I opted to buy a THD instead of building, and now I'm being driven nuts by not having a project going on the ol' workbench.

On this topic, I'd like to hear opinions from those who have functional Fender Champs--what you like about 'em, what you don't. I'd especially like to hear from folks who've set up the Champ to power 2x12 or 4x12 cabs. Talk to me about the sound--classic rock n roll, blues, etc., and where you think this amp fits.