IM freaking out please help

[scaredashell]

Last night I was at a small gig had to depend on house help to get gear in and setup well long story short someone tore the speaker cable and the jackplate right out of my marshall cab I had a heavy duty speaker cable now im freaking out because I turned my amp on and it was either a dead short or complete open with the volume on two or 3 probably on for a minute or so before I knew there was an issue no one told me they dropped the other guitar players cabinet near mind while walking by with it they obviously didn't notice that it tore my cab up but now the issue is the amp sounds different to me today it could be psychological but I don't know so how bad could it be if it does indeed sound different 

[dude]

If you don’t know much about how an amp works, find a reputable tech to have a look.                       


al

[scaredashell]

no I know how tube amps work that's why im worried but people have mixed opinions some say a dead short is fine for a short period of time others say open circuit is fine for a very short time

[newguitarsmell]

There are so many things it could be. I'm sorry this happened. If it were me, I'd see an amp repair person. I hope you're in a town that has a good one. It sounds to me like if it's shorted or all on - at 2, something else got jiggled around.

[scaredashell]

yeah its bad it a handwired Traynor amp thing was a Marshall killer now it sounds like A marshmallow killer

[John]

but now the issue is the amp sounds different to me today it could be psychological but I don't know so how bad could it be if it does indeed sound different

But it's still working and still gets loud?

[mresistor]

Can you plug it into a different cab?  I would determine if the cabinet or speaker cable is damaged prior to "firing it up". 

[scaredashell]

yes the cable is a new cable and what happens is when I turn it on it sounds normal then after about 2 minutes or so the volume drops to about half

[Joel in Texas]

What model Traynor is this?  Knowing this kind of information might help some people give you advice about things to examine, and appropriate next steps.  FYI, I have a YBA1 Bassmaster MkII.  Any chance that is your model too?

[scaredashell]

ygl1

[Joel in Texas]

OK, so the YGL1 is a newer-production ~15 watt amp, using two el84 power tubes, and two 12ax7 preamp tubes.

Does that sound like your amp?

I see a schematic on p.8 of the service manual, found here:
http://traynoramps.com/downloads/servman/sm_ygl1.pdf

If the current state of your amp, per your past posts, is that it works but drops volume after a few minutes, I do not have great ideas yet about the exact nature of the problem.  I work on amps as an amateur, and the real experts on this form probably will not be able to help you much without more info from diagnostic steps taken on your amp.

My own guess right now based on limited information is that you do not have a "catastrophic" problem.  The amp might need repair, but it is probably not toasted.

The two most expensive replacement parts in your amp are the Power Transformer (PT) and the Output Transformer (OT).  My own guess, if you are currently getting sound through the amp at all, is that neither of these are ruined.  Even if they were, you could probably get a decent new or used PT for something like $60-100, and a decent new OT for something like $40-$80.  But again, my guess right now based on limited information is that these are not the cause of the behavior you described.

My best advice, which matches what others have said, is to take it to a competent tech.  Do you know of one in your area?

Another question - have you ever worked on tube amps?  For example, have you used a multimeter to check voltages etc. in an amp?  Note: this is not something you should do unless you have some understanding of electronics and also understand the potential for injury and/or death and how to avoid it when working on amps.

[scaredashell]

yes that's the amp and yes I do get sound but it looks like one of the EL'S is dimmer than the other and no I have always been told do not touch anything inside my amps but the tech and only tech within about 200 miles from me wont touch it he does not work on Traynor amps only marhsall fender you cats are great on here I really appreciate all the comments but I feel comfortable poking around in the amp I know that over 400 volts are present in the amp and I have a good fluke multimeter

[shooter]

I feel comfortable poking around in the amp

then it sounds like it's poking time 
and He's not a very good tech if he only looks at 1 type amp

[scaredashell]

no no hes really good he has done work for some big names but he only works on fender and marshall amps he explained he said he has few limits to what he can do to a fender or marshall and he pretty much knows by heart what sounds good on those style of amps but as far as Traynor he doesn't like how they do the tone stacks

[ALBATROS1234]

sounds like he only works on old amps because they are far easier to work on. newer tube amps are a huge pain in the ass. if hes a good tube tech then hes a good tube tech but probably doesnt want to mess with circus boards and such. i am only a couple years into working on tube amps and i am comfortable working on anything pre early 70s because its all point to point or turret boards and its easy to get to stuff and change components. i got a 2004 blues deville ri amp at my house opened it with a schematic and my first thought was, why is there so much garbage in this thing and how are you supposed to change components. it was a royal pain so i will check something ike that for a friend to see if its something simple to fix but if i cant take care of it within a few hours its not worth the time and effort to me. i truly dont get why the newer amps have so much garbage in them when all you need is a simple time proven design to sound amazing.i am only speculating but maybe its not worth his time to mess with anything but classic handwired stuff. 

[shooter]

well, actually, I draw the line at PCB china style, not worth the return on investment

[scaredashell]

yeah and for me im a cable and amp kinda guy I own one effects pedal its a MXR analog reverb that's it I don't like amps with effects loops in general the other amps I own do not have them its just this one sounds so insane good but I guess its just a write off by the sounds of it but the chassis is useful and the cabinet is solid birch plywood so its good but im guessing what ever has happened its going to be an ass to repair

[ALBATROS1234]

What i advised my friend with the blues Seville to do was let me rip out the circuit board and use the trannies to rebuild it to a 5f4 super circuit on a turret board. So he's debating that now

[Joel in Texas]

I think there are several possibilities for the outcome here, which could range anywhere from something simple like 'replace one tube and you're back in business' to 'tear down the whole thing and rebuild from scratch'.

Scaredashell, you said you liked the sound of the amp before the problem.  So I'm guessing if it can be fixed easily, that is what you would prefer to do, rather than tearing down the whole thing and rebuilding into a new amp.  Right?

Even before opening it up and poking around, I would start by trying to isolate the problem to either the preamp section or the output section.

Because this is a modern amp, you have pre-amp out and power-amp in jacks.

I would start by removing the two el84 tubes, leave the 12ax7s in place, and plug a guitar cable from the pre-amp out jack to the input of another amp. Do you have another guitar amp you could do this with?  Or a PA system?  Any audio amplifier could be made to work, but something designed for musical instruments would be simplest, and best.   

Anyway, with those power tubes removed, and the preamp of the Traynor running into another amp, see if the problem happens. You described the problem as it sounding fine for two minutes, then volume drops after a few minutes.  Does this still happen when bypassing the power amp?  Note the tone will not be exactly like it would be going through the power section and speaker of your Traynor.  But you are not trying to reproduce the tone of your amp exactly with these steps - you are just checking to see if the 'delayed volume drop' problem is happening in the preamp section.

Also, when you remove those two el84 tubes, take a close look.  Any signs of burning, discoloration, or other visible signs of problems?  Particularly with the one you said looks like it is dimmer than the other?

Finally, if anything nutty happens when you are trying this - sparks, smoke, poltergeist, tornadoes, etc. start shooting out - shut the amp off and report back.  My guess based on your description so far is that checking the preamp section in the way I described should be fine to do.  But be alert, and shut it down if anything nutty starts happening.

Try these two things, and report back.