my amps broke and i was wondering if anyone has any ideas....

[J_182]

right well basically.....

i have a 50W marshall G50R CD and well its broke.....

when i plug it in .... nothing happens...

its not the speaker because if i plug a jack into the CD input (wich runs straight to the speaker) it works...

and another thing... when i turn the reverb dial is crackles so im guessin it has something to do with the reverb .....

p.s. try to dumb whatever your replies are as i dont realy know much about the inside of my amps...

[petemoore]

  There is potentially lethal high voltage in there, I recommend and amp tech.
  No output/Reverb knob crackles when twisted...I'd guess are not necessarily related.

[pi22seven]

+1 on going to see a tech.

Poking around inside of an amp is totally different from poking around in a stompbox.

[R.G.]

+ 100 on going to an amp tech.

I mean this all in the spirit of friendly advice. From your post, you have little or no electronics skill or experience.
Therefore the number of things you could fix are limited to things outside the electronics chassis, like fuses, knobs, speakers and speaker wiring.

Given that it crackles when you turn the reverb knob:
- it's not a fuse, or it would not crackle
- it's not a speaker, or it would not crackle or let you hear the CD
- it's not a speaker wire or it would not crackle or let you hear the CD
- there is power going to the innards, which makes it dangerous.

So the only logical thing to do is to take it to someone skilled in how to fix it. There are no simple, easy fixes for this that you are likely to be able to do.

[J_182]

yeah i guessed you would all say that....

thanks anyway....

[petemoore]

  9V is a great number for a starting point to learning electronic basics.
  Very similar to HV circuits, but without the potentially lethal voltages.

[J_182]

yeh..........like the guy said earlier its pretty obvious i have little if any knowledge of electrics....

therefore the only responce i can give to that last thing you just said is....

eh??

[R.G.]

yeh..........like the guy said earlier its pretty obvious i have little if any knowledge of electrics....

That's no sin - every single one of us that frequents this forum once knew as little or less about electronics. Most people come here to learn more.

The only problem you have is that such learning is not instantaneous. It'll take some time, and you'll probably need that amp before then.

So take it to a tech, but then come back if  you have any inclination to learn some electronics. It  may bore you to tears, but if it doesn't and you learn a bit, you might wind up an electronics junkie ... like me. 

[J_182]

nah i didnt come on here to get my amp fixed.....

i came on here coz a freind learned a lot on here n recomended it...

i am pretty eager to learn about what goes on on the insides of my equipment so i guess my first step is to file through all the posts n hope i understand at least a few of the words......

if not then maybe i shall resort to tears...

[jonathan perez]

possibly the input jack could be disconnected. i repaired an amp with the similar problem. but then again, i was a tech.

[Roobin]

af not then maybe i shall resort to tears...

Don't give up! What you could possibly do is take your amp to a tech, and sit there and ask him what he's doing, ask questions, so you see the innards, but under experienced hands. OR if that isnt possible, you could ask him/her when theyve finished if they could open it up and show you where it went wrong...

Failing that, start on stompboxes!

[J_182]

well i know what the inside of my amp looks like....

within a week of having my first amp it was in pieces on the floor....

but i know for sure i havnt broke it.....

because non of the wires have been touched and the board hasnt been altered in anyway....

its mainly just me messing twith the hardware of it....

[8mileshigh]

If you want a great pedal building tutorial, order a Tweak-O from small bear electronics.  I'm not crazy about the sound of it but the experience of building it was priceless.
Now I can build circuits from schematics and they actually work.

Having said that, I would never consider messing with my amps due to the lethal voltages stored in the capacitors.  When I get the courage, I'm going to order a Weber amp kit and try and build it but I'm going to thouroughly learn how to bleed electrolytic caps prior to that so I don't buzz myself.

8

[Peter Snowberg]

Welcome to the forum.

Amp questions often get the same response here because it really is dangerous to work with multi-hundred volt supplies. In your case the amp is not a tube unit so much of the caution may have been laid on a bit heavy, however dead is dead.

Is this the unit?



The fact that the CD input works means that it's something in the preamp and it should be pretty easy to track down and fix. The voltages involved in that part of the circuit are pretty low. If you observe propper precautions like keeping one hand in your pocket while testing the circuit, you should be just fine.

The best place to look next is to get a schematic. With that and a meter it should be pretty easy to find the fault. Without the schematic, you need the electronics background so your options then become the amp tech or being without the amp for a long time while you learn.

As R.G. pointed out, we all started at the same place so welcome aboard the journey .  Everyone here is still learning. (hopefully)