Anybody here build their own amp?

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metalhead28

metalhead28

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I'm seriously considering diving headfirst into building my own tube amp(s). I've picked up a decent book on the subject, and I've been lurking over at 18watt and AX84 for a little while. I'm very confident in my ablity to pick up new things, and I'm starting to think this would be a fairly easy undertaking.

I would love to have a little low wattage monster for the studio and I'm pretty intrigued by the "P1 High Octane" plans over at AX84.com.

Any of my homies here at HR get into that?
 
metalhead28 said:
I'm seriously considering diving headfirst into building my own tube amp(s). I've picked up a decent book on the subject, and I've been lurking over at 18watt and AX84 for a little while. I'm very confident in my ablity to pick up new things, and I'm starting to think this would be a fairly easy undertaking.

I would love to have a little low wattage monster for the studio and I'm pretty intrigued by the "P1 High Octane" plans over at AX84.com.

Any of my homies here at HR get into that?

Man I've been reading at both places for probably 2 years and I picked up a couple of books too. One of these days............I want to build a 36 watt. Don't be like me. Just jump in and get some hands on experience.
 
i've built and designed several... but not for me... i'm a keyboardist... it's not that hard attention to detail is everything... pm me if you want some input...
 
I'm also looking to do this pretty soon. Working on 12AX7 preamps first to get comfortable working with tube voltages and separating signal from AC lines. Doesn't seem too hard but high voltages still make me a little bit nervous.
 
Here is the long version of how I dropped a tube pre stage into a Peavey RAGE!:

http://www.homerecording.com/bbs/showthread.php?t=181098

Short version, I designed a 12AX7 stage to drop into a little practice amp, between the stock opamp (which still drives the clean channel) and a solid-state output. It was fun as hell!

Pros: the hybrid design means no output transformers or power tubes, which saves a lot of dough and makes it easy to build. It uses a much smaller power transformer too, and a solid state rectifier.

Cons: No power tubes, output transformers, or tube rectifiers!
 
Interesting and fun, yes; easy, no.

I've built a couple of amps, and they are a strange beast. You look inside a tube amp (particularly a good, i.e., simple one), and they look so easy. But the littlest things can make a big difference. Just they way you dress your wiring can be the difference between an amp that works, and one which squeals like a banshee. On my AC-30, I had one channel (the top boost channel) working perfectly, but the Normal channel is noisy as fuck. The thing is, there is NOTHING in that channel which could have been the problem. Litterally. I got rid of the second input jack (on all my amps, I don't like the mix resistors) and got rid of the mix resistors. So, from the input jack, it goes through a shielded wire to the grid on the preamp tube. After that, it goes through one capacitor, then to the volume control, and then through another shielded wire to the PI. That's it. That's the whole channel. I STILL don't know what the problem was, but I eventually just re-did the whole channel (didn't take long), and it went away.

None of this is to discourage you, because building my amps was great fun, and tremendously educational, but it is ALSO tremendously frustrating at times. The best advice I can give you is: 1) do a kit the first time, and preferably for a dirt simple amp (a champ is a good one, so is the AX84); 2) find someone who knows what they are doing, buy them a couple cases of beer, and make friends with them - there is nothing more valuable when building an amp than assistance from someone who has a fucking clue; 3) Remember, there is some shit in there which can kill you if you fuck up - BE CAREFUL, and never assume that the caps are discharged, meter them.


Oh, and one other bit of advice - NEVER solder in your underwear. Don't ask, just trust me on this one.


Light

"Cowards can never be moral."
M.K. Gandhi
 
Light said:
I've built a couple of amps, and they are a strange beast. You look inside a tube amp (particularly a good, i.e., simple one), and they look so easy. But the littlest things can make a big difference.

Amps and pedals do look deceptively simple to build. A friend opened up his Landgraff overdrive to show me what's inside. I was like, "that's it?". There's barely anything in there at all but he sells plenty of them at $400 a pop. There's probably $25 worth of parts in one of those pedals.
 
Light said:
Oh, and one other bit of advice - NEVER solder in your underwear. Don't ask, just trust me on this one.
Uh....uh.......ok.
 
Make sure you have someone to help you if it's your first one. Also start out small and work your way up. I started with an 18 watt Marshall and it took all of about 15 minutes to realize that I was in over my head. LOL, the amp works and sounds great!!!!!!!!
 
Micter said:
Make sure you have someone to help you if it's your first one. Also start out small and work your way up. I started with an 18 watt Marshall and it took all of about 15 minutes to realize that I was in over my head. LOL, the amp works and sounds great!!!!!!!!

Which one did you build?
 
Also, a very good idea is to create a power break switch that's triggered by foot pressure. This has saved my life a couple of times. When you're shocked, your body tends to tense up, and you will push down with your foot. So when that happens, bam, power's cut completely! A $3 piece, 15 minutes of work, seems worth the effort for the possible payoff (life!).
 
I'm in the process of building a "firefly" from the ax84.com site. It's about 3 watts and uses 2- 12ax7's, and both sides of a 12au7 for the power tube. Some of the clips I've heard sound pretty good. It's a real simple circuit. Most of all the parts are pretty cheap because of the low voltage it needs. The power and output transformers are about $30.00 each. And you get to crank it without the neighbors calling the cops.
 
Thanks alot for the input guys. Yeah, when I said it looks easy....I didn't exactly mean EASY easy. Just not as hard as I would have thought.

I'll definitely start with one of the kits. I'm probably going to buy the "High Ocatne" kit from AX84. Not only is the documentation there pretty good, I've also found a few sites where people have documented their own builds very thoroughly...lots of pictures!

I'm a detailed kind of guy, so I expect I could really get into this sort of thing. I'll keep you guys posted.
 
I'm working on effect pedal #3. First was a kit and the second was my own design. The current one is a modded design. I think a few pedals would be a good place to start before trying out an amp.
 
It's fun soldering and putting one together by using a layout.
I would learn how to read schematics if you don't already know.

I think it's important to know why and how things work. Anyone can paint by numbers, and if you don't know why this part goes here and this value is in at this spot, you might as well just buy an amp.

I figured out that I didn't have to know a lot about an amp to be a guitar player.
 
I have converted a few old tube HiFi amps to guitar use. Pretty easy depending on the quality of the unit you start with. Find them at fleamarkets and garage sales. Best sounding....EICO (2 6bq5's)


chazba
 
Thought I would bump an old thread. Just took the plunge on a Misssion 5e3 type. Expecting a little down time in November. Idle hands and alll.........consequences. I will let ya know when my hair starts coming out. (by the handful).
 
I've built several amps the last year. It's a very addictive hobby!

The AX84 kits are very good for beginners (i myself started out with the HiOctane, which is decent). Most of my builds are either from or based of the kits at http://ceriatone.com/. Huge selection, and good service.

But my favourite is the 18watt Lite. Best recording amp you'll ever come across (if you like classic marshall tone that is). Check out a partial kit here: http://guitaramplifierpcbs.com/liteiib.aspx
 
I built a Trinity TC-15. GREAT amp. Take your time and make sure you understand the steps before you solder and you should be fine.

And don't solder in Light's underwear.

Best of luck.
 
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