View Full Version : Help Smoke & now no sound
Stripped the flextone 2 head to its metal casing (re tolexing the wooden chassis)
Plugged into 4 x 12 8ohm marshall cab, checked impedance on the back of amp was set to 8 (switch is slightly loose - could have been set to 4 by mistake)
Switched amp on, and did a reset on the presets by holding in 4 buttons, next thing, i see and smell smoke coming out the top, looked inside and saw one of the components (couldnt tell you which) glowing red hot orange!!!!
Turned off, checked impedance was defo at 8, plugged back in, power and usual noise you get through the cab when its turned on (I mean the pop when you plug a guitar in noise in case anyones wondering)
Plugged guitar in, as no more smoke/smell/orange glow and no sound whatsoever!!!
200watt solid state amp incase that makes a difference. This amp stopped production 6 years ago so warranty = no go
HELP!!!
Midnight_Highway
12-10-2009, 11:28 AM
Smoke may mean you have a short circuit somewhere. But the reason you have no sound now might be simply because you blew a fuse. At this point, I'd just let a professional take a look at it... I had a similar issue once--destroyed my amp in the process. :D
George
Took some pics and let paul numbers look, he says one of the resistors next to the white ceramic resistor that glowed orange hot has a crack in it, problem is determining what caused the surge, no point in replacing if its gonna happen again, line 6 service centre...one in the UK, 250 miles away :( Phone call, bank card and package the thing up im guessing...
mmmtacos
12-10-2009, 12:20 PM
My son blew a fuse on his tube amp. He never figured out what caused the surge. But it's holding so far (almost 4 months)
I would just weigh out the cost of replacing whatever is wrong with the cost of a new replacement.
Maybe a cheap fix, and mabye it won't do it again....then again................:whistle
not sure where the fuses are on the amp, i know the two resistors definately need replacing though
Anyone else got any input?
kb7010
12-10-2009, 02:32 PM
Anyone else got any input?
You know the answer and I hate to remind you.. but a PRO is going to HAVE to look at that bud.. sorry... best advice I can give ya..
Cygnus X1
12-10-2009, 02:50 PM
True 'dat.
Take it to a pro, then make a decision.
Can you post a picture of the board and components that are cooked?
The white box was glowing orange hot and notice the crack in the blue resistor
http://i13.photobucket.com/albums/a267/Mac_wylde/10122009033-1.jpg
Are you sure the "white box" was glowing, it doesn't look fried.
PacerMedic
12-10-2009, 05:16 PM
Bit of a lemony snicket, mate. Seems your amp gave up it's smoke! This of course, is a proper Bristish saying for "done blowed up". You're in luck though, being local, you can ring up the Lucas Electrics Company and order a jar of "Electronics Smoke" factory direct! Any good Jag technician can install the smoke for you for less than 1,500 quid! Do it! Do it now!!! :thumbsup
Sorry Mac, I couldn't resist the smoke skit. I honestly can tell you that Paul### should have the knowing of the way to fix that beastie for ya tho! :toast
By the looks of the picture it looks like the resistors R21-the big resistor with the crack, and the two surface mount resistors r10 and r27 are fried. The big white box I believe a 330 ohm resistor and by appearance it looks ok. The only way to tell for sure is to unsolder one leg off the board and read across it. The bigger resistor looks to be a 8 ohm resistor. The problem is something else in line with these probably took them out so replacing those resistors wouldnt fix the problem.
Q14 and Q22 should be transistors and I cant see them very well in the picture. Do they look ok?
that sucks, bro... hope you get fixed soon.
amerturk
12-10-2009, 06:36 PM
My guess is one resister went bad overloading the one that blew. 2 of those badboys will cut it in half and when one goes, one gets the load?
Sounds like a simple fix...I hope and good luck with it.
side shot of cracked resistor, pic taken from side with no crack, notice burn marks at the left soldering leg
http://i13.photobucket.com/albums/a267/Mac_wylde/10122009035.jpg
pcb board over shot, mounted to the back of what looks like a heat sink, 3 cable plug into the board, as you can see one then 2 at the other end.
http://i13.photobucket.com/albums/a267/Mac_wylde/10122009031.jpg
pcb board over shot, mounted to the back of what looks like a heat sink, 3 cable plug into the board, as you can see one then 2 at the other end.
http://i13.photobucket.com/albums/a267/Mac_wylde/10122009031.jpg
Also look at the big blue capacitors in this picture. Are all the tops of the caps flat? If any of them are bubbled or rounded on top it is a good sign of them being bad. The one on the bottom right looks rounded on top.
I'll check that capacitor, the one next to the black pic chip yeah? just above the FCT 12 sticker?
Question really is what caused it? Could setting the impedance to 4 instead of 8 due to the faulty switch have done it?
KramerBassFan
12-10-2009, 07:26 PM
Solid State Amps are usually more tolerant of Mismatched impedance loads, just as long as it isn't lower than the amps output...
KramerBassFan
12-10-2009, 07:29 PM
Also, have you touched any part of that PCB recently?
The static from a human touch can cause problems with Transistors, and Integrated Circuits....
(Somebody correct me if i'm wrong?)
not touched the pcb and the cab is supposed to 8ohms and I have a feeling the amp was set to 4 because of the faulty switch
I'll check that capacitor, the one next to the black pic chip yeah? just above the FCT 12 sticker?
Question really is what caused it? Could setting the impedance to 4 instead of 8 due to the faulty switch have done it?
Yes the one above the sticker looks rounded.
with an 8 ohm cabinet it wouldnt matter if it was set to 4 or 8 ohm. It wont be a problem.
damn, this means I cant determine what caused it :D
Anything to do with I didnt have the amp in its wooden chassis (gonna re tolex it) and plugged it straight in, the casing is metal but i dont see how that would effect anything as nothing is touching it.
Touching the pcb with my hands? perhaps when i accidentally unplugged the top ribbon cable removing dust from the back of the heatsink the pcb is mounted on
Im stuck otherwise, didnt have a guitar plugged in either when it went.
KramerBassFan
12-10-2009, 07:54 PM
Hmm, that may be true....
If it's a little IC or something that is gone, it would be very hard to get to the bottom of it. :censored :ninja
ac30guy
12-10-2009, 10:04 PM
maybe it's a sign that it's time to go to a non-digital amp?
_xxx_
12-11-2009, 01:07 AM
With electronics, you can say nothing just by looking. You have to measure it properly. Let a pro take a look at that before you completely kill the amp.
Ive already had tube amps, solid state amps, rackmounted power amps, this was bought solely because it was a steal at £100 and there is no other modelling that is as good as line 6 end of really.
Taking it to the shop today see what he has to say
It is good idea to have a tech look at it and if he does repair it tell him to write down what components he replaced. I'm just curious. I always try and repair my own stuff but I've been doing it for awhile. If you dont know what your doing you could do more damage than good. But hey no guts no glory:D
With electronics, you can say nothing just by looking. You have to measure it properly. Let a pro take a look at that before you completely kill the amp.
That is not always true, I have fixed many things by just looking but I will agree that further troubleshooting doesnt hurt.
ac30guy
12-11-2009, 01:27 PM
there is no other modelling that is as good as line 6 end of really.
I've heard the Fractal Audio Axe FX is ten times better than anything line 6 has on the market...im not a fan of digital...the distortion just isnt there... but if you must have the best, I've heard the Axe FX is the best available...and they update regularly, unlike Line 6
I've heard the Fractal Audio Axe FX is ten times better than anything line 6 has on the market...im not a fan of digital...the distortion just isnt there... but if you must have the best, I've heard the Axe FX is the best available...and they update regularly, unlike Line 6
Working as a product tester for line6 tells me otherwise, latest software autoupdates and i could out distort any sound you could afford with tubes or bigger transistors
Did you ever get this repaired? If so, what was the fix?
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