How did you get started building/fixing/modifying guitar amplifiers?

[Ken]

When I was 12 I bought a Radio Shack strobe light kit. It took me an hour, but I soldered it all together and I had a strobe light! That was my first electronics project.

Then when I was playing guitar at 17 I had a 1960's vintage Epiphone amp (only 10 years old at the time LOL) with four 8" speakers. One day it stopped working and smoke filled my bedroom (no, not the good kind). Having no money and indifferent parents, I went to the public library and got a book on amp repairs. I read where if one of the huge resistors connected to a huge capacitor is smoking, replace the capacitor. While it didn't have the dire warnings about imminent death, I did manage to not die replacing the capacitor with one I had from some junk radio. And the amp worked again!!

That's about it for me to this day (I'm now 51), which accounts for all the posts I make where I speculate on solutions but the true techs need to chime in with better info.

Ken

 

[rjohns1]

Here we go again. Wilder, why is it your mission in life to keep people from getting started? So what if Joe Blo wants to install a tranny, and doesn't know how to read the diagram. Is it that hard to tell him which wires go where? Really? Why do we users have to bow down to the tech gods every time? Does it piss you off that more people than ever want to do it themselves rather than pay you their hard earned money? Is that the real underlying reason here? Dude, the economy is down, and people are always finding ways to slim down the budget, they might not be able to afford to have a tech do it. That is why guys come here, to discuss things, and get info. If you don't want to tell the kid how to do it, then don't. Add in all of the bad techs out there, and the horror stories, and some guys just might not trust their amp to anyone. It's that simple. Get off your almighty tech pedestal, you are not better than anyone else here, just because you have learned ON YOUR OWN the same way that these kids that come here might be trying to do. Get over yourself already.

 

[chuckharmonjr]

Ya know RJ...this is actually a really good thread. I think it is therapeutic for a bunch of folks that have some knowledge...even more so for those that dont....its a reach out-call out-talk it out kinda moment. Don't yell at Jon....Jon is ok...he is what he is...we are what we are...and that is what this thread has evolved into. Let it flow without flame...let it evolve on its on.

 

[Jonathan Wilder]

Here we go again. Wilder, why is it your mission in life to keep people from getting started? So what if Joe Blo wants to install a tranny, and doesn't know how to read the diagram. Is it that hard to tell him which wires go where? Really? Why do we users have to bow down to the tech gods every time? Does it piss you off that more people than ever want to do it themselves rather than pay you their hard earned money? Is that the real underlying reason here? Dude, the economy is down, and people are always finding ways to slim down the budget, they might not be able to afford to have a tech do it. That is why guys come here, to discuss things, and get info. If you don't want to tell the kid how to do it, then don't. Add in all of the bad techs out there, and the horror stories, and some guys just might not trust their amp to anyone. It's that simple. Get off your almighty tech pedestal, you are not better than anyone else here, just because you have learned ON YOUR OWN the same way that these kids that come here might be trying to do. Get over yourself already.

This has nothing to do with my ego or me trying to get business, etc etc. If you re-read my original post, it simply states that while you have to "start somewhere", that "somewhere" to start is not just "jumping in and poking around a high voltage device".

Like most around here, I couldn't trust people with my gear. Did I just jump in and start poking around to "get started"? No I didn't. I started learning general electronics, how to read schematics, understanding current flow and basic valve theory BEFORE I ever even considered poking around a high voltage device. Why did I do that? Because I was well aware of the risks involved with working on high voltage devices. Therefore I wanted to arm myself with as much knowledge as possible prior to ever tackling something of that nature. I also wanted to "learn amplifiers", and I knew that "learning amplifiers" involves much more than simply learning how to go through the motions of changing out components.

Now...does that make me "better" than anyone? No it doesn't nor did I ever claim that it did. Furthermore, I am not "discouraging people from learning". I am discouraging people from thinking that they're going to "learn" by "just jumping into poking around high voltage devices with zero backing knowledge". Why? Because you won't. All you will learn is how to go through the motions of changing a component. You won't learn "why" you're changing that component or what changing that component will do nor will you learn the importance of electrical safety and why we do/don't do certain things. You won't learn current flow, how to read schematics, etc etc. It is these very things you "learn" in order to "learn amplifiers", and if all you're doing is learning how to go through the motions of changing a component, you're not "learning amplifiers".

Lastly, if you're not "learning amplifiers", then you're constantly having to have someone hold your hand everytime you want to do something to your amp, which again if you're having to do that all the time you're not really "learning amplifiers".

You can give a man a fish and he'll eat for a day. But TEACH a man to fish and he'll eat for a lifetime. The issue here is that people don't want to learn and you cannot teach those who don't wanna learn.

 

[TradAmpGuy]

Good thread...

I started tinkering with everything my parents bought me as a kid. I was always wanting to know what made things tick, so I took everything apart... some of it even went back together again LoL!. I was always fascinated with motors, wires, lamps and batteries and still remember my first real circuit. I built an alarm for my room when I was about 10 or so. A home made buzzer, battery some wire and some copper strips for contacts. Problem was it only buzzed for the second the contacts we closed. So using the buzzer project I made a relay and wired it to latch closed when the contacts were made. I was pretty proud of myself for that one

Later on I took a few years of high school electronics... ahh Mr Knapp was a pisser. He always had a story to teach you something and it always stared the same way... "I had this friend once, he's dead now, ..."

Got into amps just because I wanted to know what made them tick, where and how the tone was affected in different amp designs. Still have a lot to learn which is why I have been lurking about here for the past few years and finally joined when I felt I had something to give back. There is so much info available if you want to learn, the trouble is sifting though the chaff. If you read enough sources though, you will start to see who knows and who doesnt. As for me, I tend to keep my mouth shut unless I feel Im sure on something... turns out I should trust myself more because I see some answers here and think "I was going to post that but I wasnt 100% sure so I didnt". Guess Id rather not be the one to give the wrong advise.

I would just like to give a big shout out to all the real techs here that take time out of their day and give this stuff away for free. You guys know who you are and I would want to offend by forgetting someone.

My advise, learn everything you can. Build a man a fire and you keep him warm for a day... set a man on fire and you keep him warm for the rest of his life

 

[thetragichero]

i still smell a pissing contest... better get the urinal cakes!

 

[thetragichero]

some of it even went back together again

wow this is a feat i was NEVER EVER EVER EVER able to duplicate
good thing they never let me touch their new/working stuff!

 

[Rockraver]

I'm of the same mindset as Jon. I want to know WHY i'm changing this cap or that resistor. I don't want to just build kits (even though it's still very satisfying when you've completed a kit and it actually works!).

As far as my story goes..., it started when I got a job as an electrician's helper sometime in the late 80's. I loved that job and I found the subject of Electricity to be fascinating. I tried getting in the union but unfortuantely, I didn't know anybody so, I never got in. I decided to move onto Electronics proper and so, after getting my GED, I went to a local Community College and signed up for an Electronics Technolgy degree. I got thru 3 semesters ('92 to '93) but then, had to drop out due to financial reasons.

I didn't go back to school til '98. I took a one year certificate program and man, I aced that shit! 4.0 all the way. You see, I never stopped studying electronics after dropping out of college so, alot of the stuff was still kinda fresh in my mind. Funny thing is, I was, let us say, a very enthusistic participant of "chemistry" during the 80's and it didn't stop til the mid 90's. It's amazing I retained anything at all. But, I did and, I excelled at this shit.

Unfortunately, none of it dealt with Tube technology and, I spent all of the 2000's working on a career in computers. So now, a good deal of what I knew so well back then has kind of slipped away. As a result, I am "almost" starting from scratch again. The desire to learn everything I could about tube amps was re-awakened when I had finally re-integrated myself succesfully back into society and saved enough money to finally get a Marshall again a couple of years ago (wasn't making a whole lot of money, even though, I was a computer tech).

So now, as a result of a lot of dead brain cells and being away from electronics for nearly a decade, I find it a challenge putting all this knowledge together. There's so much info out there and, more often than not, guys like me need someone to help them put it all together.

We (us newbies) all wish we could hang out at someones shop and learn everything we can from them but, alas, such is not our fate. Most techs guard their secrets and only let you in for a peak at best.

That being said, I would like to propose an idea (to anyone in my area at least). Over the last year or so, I have discovered these "amp building weekends" and seminars and stuff and I thought to myself, "why can't a bunch of us "know nothings" start our own "meetup", as it were, and learn/practice/study how to fix/mod/repair amps together at someone's house or basement nearby". We could scout for willing donors who need they're amps repaired or who would want certain mods done or something and do it for free. Maybe someone wants to buy a kit and we could all help such person build the amp and maybe mod it along the way.

Anyone in the northern NJ area interetsed in such a thing? I fervently believe that 2 heads are better than one and between all of us, we could all learn alot of stuff and probably fix/mod/build a bunch of cool amps.

Whadd'ya say guys?

 

[S.A.T.O.]

I build DC power plants for a living so I'm working with rectifiers, inverters, transformers, and capacitors all the time; -48v plants (2000 to 4800 amps) mostly but also -24v and +140v. Years ago my company decided to stop educating people in their respective fields (cost reduction type stuff) so a lot of what I've learned I've picked up from the old timers that have since gone and the rest I've done on the fly.
I'd like to get into repairing amps, I feel I have a solid base. I'm definitely comfortable working around this stuff.

 

[LBKENNEDY]

this is my second post.
i am an afl cio federally trained journeyman instrumentation and controls technician
since 1979.
not a genius, trained to consult documentation for the wide variety of things electronic
i maintained , early chart ecorders were driven by vacuum tubes.
seriously if you are not trained or guided by one who is, you are playing with other
peoples lives as well. a mistake on that chassis could kill the entire band.
a man has got to know his limitations, inspector callihan.

 

[Ken]

a mistake on that chassis could kill the entire band.
.

Really!? I suppose if they were all holding hands and the ground became live...but what scenario did you have in mind?

Ken

 

[RiverRatt]

My uncle is an electronics engineer and went around to all the elementary schools when I was a kid demonstrating the dangers of electricity. I learned to be careful from him, and I also learned how to troubleshoot from him. I would never call myself a tech, but I know enough to bias my own stuff and troubleshoot it and replace a bad cap or resistor without frying myself. I'd never work on someone else's stuff, though.

He used to have me build electric motorsm crystal radios, electromagnets and even model rocket launchers with him when I was just a little kid. I got addicted to tinkering when I took apart a slot car and hooked the little motor up to a 9-volt battery and a speaker from a radio and figured out how to change the speed (and pitch) with a potentiometer. My granddad had an old soldering gun with a light on it and I would solder everything I could get my hands on. Every time I smell hot rosin-core solder I remember that gun. Every time my granddad would buy a new battery for his lantern I'd drain it in a day or two tinkering around with it.

 

[80s dude]

Short version: I learned to solder in Boy Scouts (and also learned what caps, resistors, & so on did). Didn't put that into practice 'till I got my 1st electric in 8th grade, when I swapped out the pickups. For the next few years, all I worked on was guitars, but eventually educated myself so I could work on pedals & finally amps.

At this stage, I've modded & repaired a good many amps- my own, and also for friends (I don't do this professionally). Never blew up an amp- and never received a single shock.

 

[Over Drive]

So what would one suggest for a person who has some a little soldering and electronics experience that is now interested in becoming proficient enough to safely build an amp or two if they do not have the benefit of learning from a qualified tech?

Read the above mentioned books? Start with a kit?

 

[GIBSON67]

I'm no tech, and would never claim to know anything about fixing your amp. I can read schematics and once blackfaced a late 60's Bandmaster. I love to read about tube amps and speakers but what I know is mainly general knowledge.

I plan to get more books to learn and be able to fix my own tube amps, which are currently working great. Or maybe build an amp out of a old organ...

I thought I was going to fix a 3310 Lead Mosfet amp that i had bought just for the head box, then you guys talked me out of that. I ended up selling the non-working chassis, anyway, to a guy as a build platform.

 

[SteveGangi]

I went into the Army as an electronic tech (the old 33S MOS) in the seventies. When I got out, I used the GI Bill to get my engineering degree. So now, I don't need to go hunting for a tech if something needs fixing.

 

[hbach]

Also the short version: I played with the whole lamp and battery kits as a kid. I have a mechanical engineering degree and I worked the two years after uni with programming CNC machines and PLCs.
I have a Pro Junior that I thought was OK but I wanted more, so I built a 2061 clone into that chassis this year. It's working great but there are still some thing I want to change like the transformers as I'm using the Pro Junior ones and an off-stdby-on switch.
As someone mentioned I love knowing the why and how so I've been reading all I can get my hands on.

 

[impetus maximus]

i've always been mechanically inclined. my father taught me how to solder
when i was like 8 years old. i also like to tweak and improve things.

i just started a few months ago with amps. first i learned how to discharge
deadly capacitors. also learned if you need to check voltages on a live
amp do it with one hand behind your back.

wanted to get back into playing and wanted a low wattage amp. after some
searching i found the FireFly on ax84. i did A LOT of reading before ordering any parts.
learned that there was a capacitor that made the amp dark, so i didn't use it (C8).
also found out the schematic was wrong on the output transformer wiring.
so do your research and READ READ READ!

my brother Brian (TradAmpGuy) helped me build it with turret boards.
i learned so much about tube amps and it's an experience i'll never forget!

found that the boost which enables V1 thinned out the tone.
that taught me how coupling capacitor values effect tone. swapped out the
stock .0022 µF (C2) for a .0047 µF. boost is more linear, and has balls!
so i got my first build and mod under my belt.

next is modding my 2204. 1 to improve it's tone, and 2 to piss off the purists lol.

glad to be here among all you fine techs

/max

 

[Lane Sparber]

So what would one suggest for a person who has some a little soldering and electronics experience that is now interested in becoming proficient enough to safely build an amp or two if they do not have the benefit of learning from a qualified tech?

Read the above mentioned books? Start with a kit?

The two best overall websites for this kind of info are, at least in my opinion:

How to design valve guitar amplifiers

That's Merlin Blencowe's site. It's choked full of GREAT, ACCURATE info. Buy both of his books as well. They're a bit pricey, but the information contained in them is invaluable.

Also see:

Aiken Amplification

This one is Randall Aiken's site. You can not go wrong with him either. Just click on the "tech info" tab on the lefthand side of the page and start learning.

Gerald Weber's books were invaluable to me when I was first starting out:

Kendrick Amplifiers Online Store: Books and DVDs

That should get you started.

-Lane

 

[Blacque Jacque]

Valves are definitely not my speciality.

I began with the 3v bulb, just like Jon, probably around 12-13, fooled around with other "electronic" stuff, busted some, fixed others etc etc. By the time I was 16 I'd built a few simple electronic kits. I also had a sideline for a couple of Xmas' converting 240v light sets to 12v for cars & caravans etc

I managed to get into college (Cambridge) & studied electronic engineering for 4 yrs, escaping with an HND (not quite a degree but definitely a more practical bias).

During that time I got a temp job in the summer working for a local division of Phillips, my first wage packet went on a Kay Strat copy from my cousin & a new set of strings.

After college I got a job with a scientific company making analytical equipment (GC's & flame spectro's, similar to my job at Phillips). Then moved on to another scientific company building diode lasers & piezo positioners & scanners (150 & 300v dc amplifiers basically) and who also put me through an apprenticeship in toolmaking to bring my mechanical assembly & machine shop skills up to scratch.

I quit that job around 15 yrs ago & moved into IT, but I still keep my hand in a little. I can tell which end of a soldering iron is hot & know that any cap can be hiding a lethal voltage.

I am NOT an amp tech by any stretch, but I can read a schematic & understand it's basic working & fault find it. Getting a working band up & running again about 12 months ago renewed my love for Marshall & eventually led me here.