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#1
I've searched the internet alot for this topic, but to no avail. Everthing I find is way too technical. I kind of want something that takes a simple and common pre-amp/amp circuit and breaks it down. Like "here's you a nice picture, this resistor does this, this cap does this. Tweak this for this effect" etc.

Any such thing? Or am I just dreaming?
#2
Even with the pictures, you still need the skills developed from past builds to tackle the fundamentals and not stuff it up completely.
Who reads sigs anyway
#3
yer +1 to strong wizard, and if you do find something on building tube amps, be CAREFUL! tubes run on high voltage.... and they take a while to discharge, u dont wana risk getting a 300 or more volt shock. Not good for the old ticker.
#5
be careful from tubes running on high voltage? if you don't connect it to an outlet, that's 0 volts...
Call me "Shot".

ShotRod Guitar Works

Custom Hand-wired Amplifiers and Effect Pedals.

Est. 2007


Source to everything I say about Guitars, Pedals, and Amplifiers: I make them.


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#6
Quote by ECistheBest
be careful from tubes running on high voltage? if you don't connect it to an outlet, that's 0 volts...

wrong. the caps can still hold voltage for a while after they have been unplugged/.
#7
Quote by ESPjohn666
wrong. the caps can still hold voltage for a while after they have been unplugged/.

we're talking about building an amp. do you plug your caps into an outlet before wiring it in your amp that you're currently building? i thought the first time i plug my DIY amp in is when i'm done building it...


so the caps don't have voltage to start with. or do the manufacturers store electricity in the caps before they ship'em to me?
Call me "Shot".

ShotRod Guitar Works

Custom Hand-wired Amplifiers and Effect Pedals.

Est. 2007


Source to everything I say about Guitars, Pedals, and Amplifiers: I make them.


UG's Best DIY PedalBoard
#8
+1 to pedal build idea, probably good idea to get some exp in putting together electronics first. Besides, pedals like the Electro Harmonix LPB-1 is a preamp in itself. It is a basic transistor amplifier, with one gain stage. Its an easy pedal build, and you can find an entire kit to build it on www.generalguitargadgets.com It was my first pedal build, and it worked so well that ive subsequently built 2 more for a coupla friends who wanted one.

Edit:
Quote by ECistheBest
we're talking about building an amp. do you plug your caps into an outlet before wiring it in your amp that you're currently building? i thought the first time i plug my DIY amp in is when i'm done building it...


so the caps don't have voltage to start with. or do the manufacturers store electricity in the caps before they ship'em to me?


Tube replacement/biasing MAY require turning the power on, AND when life is at stake, why not be cautious?
Last edited by FarewellMemory at Dec 7, 2007,
#9
Quote by ECistheBest
we're talking about building an amp. do you plug your caps into an outlet before wiring it in your amp that you're currently building? i thought the first time i plug my DIY amp in is when i'm done building it...


so the caps don't have voltage to start with. or do the manufacturers store electricity in the caps before they ship'em to me?

what about when he has to bias it or troubleshoot it?
#10
u think he would bias it with his hands? for trouble shooting, if he let the amp sit unplugged for 2~3 hours, the voltage would be gone.

i actually modded my amp, and my caps were discharged to 0.01V in 2 hours. that would hurt a lot huh?
Call me "Shot".

ShotRod Guitar Works

Custom Hand-wired Amplifiers and Effect Pedals.

Est. 2007


Source to everything I say about Guitars, Pedals, and Amplifiers: I make them.


UG's Best DIY PedalBoard
#11
Quote by FarewellMemory
yer +1 to strong wizard, and if you do find something on building tube amps, be CAREFUL! tubes run on high voltage.... and they take a while to discharge, u dont wana risk getting a 300 or more volt shock. Not good for the old ticker.

Tubes can run on 12v...

And its the big polarized caps you need to worry about more.


TS if you are serious about this go join a amp building forum. They will give you better advice than we can give. They will also be able to recomend some good books.
#12
Theres some decent info on this page. It won't answer all of your questions, but it will educate you a bit in some of the working of a tube amp.
http://www.aikenamps.com/TechInfo_2.htm

I wouldn't really even think of building until you know what all the components do (non-polarized caps, electrolytic polarized caps, resistors, transformers, diodes, pots, triode preamp tubes, tetrode/pentode output tubes, etc.)

If you do decide to build something, try to understand what everything does first, and do as others have said and make something smaller, cheaper, and much less dangerous than a full on tube amplifier. If you feel ready to build a tube amp, I don't think it would be wise to make anything above a low wattage (15w max) Single Ended amp. An SE amp would be a better choice because it minimizes on cost, it doesn't deal with more advanced devices like phase inverters, etc.

If you don't kill yourself, building and troubleshooting it should be a good learning experience.
#13
how about a tube amp kit to get started. just the first one that popped up on my list.

http://www.tubedepot.com/tubeampkits.html


and up there, it's fine to say, "be carefull", but you dont want the guy to think amp parts can kill him out of the box.
Jenneh

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#14
^thats so expensive jenny. i'd go for ceriatone or weber kits.
Call me "Shot".

ShotRod Guitar Works

Custom Hand-wired Amplifiers and Effect Pedals.

Est. 2007


Source to everything I say about Guitars, Pedals, and Amplifiers: I make them.


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#16
yeh like i said, that's an example of a kit. first came up on my list.

i didnt research or suggest That site.
Jenneh

Quote by TNfootballfan62
Jenny needs to sow her wild oats with random Gibsons and Taylors she picks up in bars before she settles down with a PRS.


Set up Questions? ...Q & A Thread

Recognised by the Official EG/GG&A/GB&C WTLT Lists 2011
#17
^okaaaaay.

^^their prices are bit better than $2000 for a tube amp kit tho.
Call me "Shot".

ShotRod Guitar Works

Custom Hand-wired Amplifiers and Effect Pedals.

Est. 2007


Source to everything I say about Guitars, Pedals, and Amplifiers: I make them.


UG's Best DIY PedalBoard
#19
id suggest building a couple pedals then maybe modding your current amp or something. I m about to build a weber 1987x kit( kinda) i built a digital delay and im building 2 more pedals before i start my kit, i also have a valve junior that i completely gutted and replaced every component so i pretty muchc consider it making an amp cuz only about 5 values remained the same plus i have some cool mods on it. on a side note if you have a parent who is an electrical engineer or something like that the ycould help you in your building
#20
^i wanna build one too... get on the bandwagon...
Call me "Shot".

ShotRod Guitar Works

Custom Hand-wired Amplifiers and Effect Pedals.

Est. 2007


Source to everything I say about Guitars, Pedals, and Amplifiers: I make them.


UG's Best DIY PedalBoard
#21
Quote by kurtlives91
^Ceriatone kits are soposed to be not the best.

i really hate to keep argueing with everyone, but i think Kerry but a ceriatone plexi kit with good results.
#22
^he never said Ceriatone is bad. just said they aren't the best. but im wondering where i can buy something better than the Ceriatone kits...
Call me "Shot".

ShotRod Guitar Works

Custom Hand-wired Amplifiers and Effect Pedals.

Est. 2007


Source to everything I say about Guitars, Pedals, and Amplifiers: I make them.


UG's Best DIY PedalBoard
#24
No offense, but Axecutioner is the only on who helped, sorry! I only say that because I've already done tons of research and every new safety article I come across I read no matter if I think I know that stuff already.

I've done many electronics projects, but none of which plug into a wall, so that aspect is new. But as far as following a schematic, I'm very competent. And yes, I'm trying desperately to learn what everything does; every resistor, every cap and transformer and tube. The thing is, I'm having difficulty finding entry level info to this stuff, hence the existence of this thread.

Most likely, I'll be modding my epi vj while I'm getting plans together for the amp, so I'll get a little experience with high voltage. (it's actually the high current that kills, not voltage). And I'm coming to realize I don't need a 50+watt amp like i'd intended, anything between 5-15 would be great for my needs.

If anyone can give me resources to understand this stuff, that'd be amazing. I feel I know what the different stages in an amp do. I just want a finer understanding of what the purpose is of each little component, so if someone could break down a schematic, I'd love you forever!



I'm considering the champ circuit. Thanks!
#25
try heading down to your local community college and go into the electronic's class area find a professor and pick his brain, the odds are that he'll be more than helpful
#27
Quote by flashbandit
No offense, but Axecutioner is the only on who helped, sorry! I only say that because I've already done tons of research and every new safety article I come across I read no matter if I think I know that stuff already.

I've done many electronics projects, but none of which plug into a wall, so that aspect is new. But as far as following a schematic, I'm very competent. And yes, I'm trying desperately to learn what everything does; every resistor, every cap and transformer and tube. The thing is, I'm having difficulty finding entry level info to this stuff, hence the existence of this thread.

Most likely, I'll be modding my epi vj while I'm getting plans together for the amp, so I'll get a little experience with high voltage. (it's actually the high current that kills, not voltage). And I'm coming to realize I don't need a 50+watt amp like i'd intended, anything between 5-15 would be great for my needs.

If anyone can give me resources to understand this stuff, that'd be amazing. I feel I know what the different stages in an amp do. I just want a finer understanding of what the purpose is of each little component, so if someone could break down a schematic, I'd love you forever!

I'm considering the champ circuit. Thanks!

Do you honestly expect someone to go through ever single resistor, cap, etc. and say what it does?

Get a book, read as much as you can, build a kit, but dont expect the internet to be as helpful as you think. i could easily tell you something wrong, you build it, get electrocuted and die. So do read you safety stuff, and get a book on electronics. you're still VERY far away from starting this. same with most people.
#28
That champ schematic isn't that bad (its a single preamp tube, a volume pot, and a single output tube, and a tube diode instead of solid state diodes). Now if it was a 100w multi channel push pull head with footswitchable reverb and an effects loop, etc., that would be a ludicrous request. That champ is pretty much as simple as it gets.
Last edited by Axecutioner at Dec 7, 2007,
#29
Aussie ebay has DVDs that tell you step by step on how to build things related to tube amps. Theres normally 4 builds on each DVD, 2 hybrids, an EL34 and an EL84 (or similar voltages). Theres even one on winding your own transformers.
Quote by kyrreca
If your EQ looks like this your audience will look like this
#30
Quote by s.r.v.
Do you honestly expect someone to go through ever single resistor, cap, etc. and say what it does?

Hey, don't let your emotions run high. I know some people on UG take the time to help people, but I wasn't forcing anyone, just a request bro. Btw, I DID intentionally pick the champ because it's simpler, and more likely to draw someone in for helping me out.

Quote by s.r.v.

Get a book, read as much as you can, build a kit, but dont expect the internet to be as helpful as you think. i could easily tell you something wrong, you build it, get electrocuted and die. So do read you safety stuff, and get a book on electronics.

I'm grateful you took the time to read this stuff, and try and help me out, so in all honesty, thanks. But, um, I was kind of hoping someone would refer me to a popular book... so... good suggestion...

you're still VERY far away from starting this. same with most people.

please keep that to yourself. If I didn't care to learn anything, building this amp would be as easy as following the countless tutorials and resources. I'm only "VERY far away" from building this because I choose to take the time to understand everything. Otherwise, the parts would be in the mail right now.


I hope to learn enough about this in a reasonable amount of time that I can develop my own modified version of an amp I like. If I'm wasting anybody else's time, by all means don't let me, you don't have to.


I hate to sound mean, so I just want to say thanks to everyone for the positive, and even negative comments. It all helps in one degree or another. Thanks.
#31
Hey Flashbandit did you get the PM I sent you?

Well anyways, I suggest you go for an AX84 P1 design (probably the Extreme Variant). Its still a very simple amp (single 12AX7 preamp tube, single octal output tube, SS rectifier). It has some things that the champ doesn't have like a tone stack (tone controls) and master volume pot.

But anyways, I'm trying to redraw the champ schematic you posted, and try to explain the functions of most of the components

Doing the schematic drawing has helped me learn a couple things like about negative signal feedback and why coupling caps are where they are

I'm thinking I might try to scrape together enough money in the next month or two and get a P1 kit.
#33
I sent out another PM with some links in it. Hopefully they can be of some use to you.
#34
axecutioner, if you wouldnt mind sending me the same PM, I've read through this post and you seem most helpful. I am a graduate of an electrical technologist college program, and have a good understanding of electronic components for the most part (their operation and what not) but I dont quite understand how they work together in an amp schematic, I am thinkin about building a Epi Valve Junior clone in the future. Specifically any enlightenment on how to pick out the different gain stages in a schematic would be helpful too, as i do not really understand that. thanks

Mike
#36
I sent you another PM with the champ schematic with explanations flashbandit.
And I guess I'll just post a link in the thread to it. And to answer your question mgp, the standard triode gain stage is probably best explained here. http://www.aikenamps.com/CommonCathode.htm

And here is my attempt at explaining the circuitry of the champ. The image is rather large (1280x1280) so I'm not going to throw it in the thread. I drew it by hand in photoshop, but it actually came out pretty well.

http://therootbeerfactory.com/champ/champschematicexplained.png
#38
I too was at one point interested in the same info as flashbandit (i.e. what resistor does what, what changing the values does, adding different components, etc) but I was always greeted with the same old "build a pedal first" and "do your research." This is part of the research folks. I'm glad Axecutioner is actually being helpful unlike the other posts. You helped me also. Thanks.
#39
get something vintage that works but doesn't work well, then fix it. Doint it this way will help you learn what each part of the amp does because each time you can change something and see how the amps sound changes. After a while you will learn the lingo and you will know how the circuits work. I tried building amps and failed horribly. Then I tried fixing amps and eventually everything started to come together. Now, not only do I know how to build amps from a layout or schematic, but I can also repair amps and I've designed a few that people have really liked. Fixing something up is the best way to learn how this stuff works.
Not taking any online orders.
#40
get something vintage

It all comes back to $$$, I'd really love to but... man I'd love to buy whatever I want but... I'm poor just a poor boy, and I need no sympathy.


So axecutioner, I spent some time pouring over your stuff and things are really (i think) coming together. I've a couple questions though.

It really surprised me to see the high voltage parts (B+2 line) on the side of the tube they're on, and I tried to figure out how they work so tell me if I'm right. I'm assuming that the when the grid is charged, IE there's guitar signal, the grid "opens up" and connects the high voltage portion to ground. Therefore, when the input signal has a peak, the output from that tube has a dip right? So I'm thinking these preamps invert the phase right?

And then I was wondering about the 2 inputs. Why does the high gain input bleed signal via the 1M resistor to ground? I'd think you'd want more signal for a higher gain.

And on the tetrode, what is the B+1 line going to pin 4 for? What's that high V doing there?

And lastly, what is the negative feedback from the speaker side of things to the 2nd preamp for? I'm guessing that signal is out of phase with the signal in the preamp, and so it cancels out, right? Why's that important.


EDIT: Oh, might I also ask, what's the grid resistor for?
Last edited by flashbandit at Dec 8, 2007,
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