my jcm800 modded 2203 died last night..help

AllSheWrote · 11-06-2009, 08:53 AM

yesterday, my fja modded 2203 reissue came in (has a heyboer transformer, depth mod and mid sweep mod)..i was so excited...got it from a reputable seller...turned it on and was in HEAVEN for the first 5 minutes...i started playing with the volumes...i had the preamp around 1:00 and master around 10:00 when i was loving it..that's normally how i run an amp....i turned the preamp way down and cranked the master..then started turning the preamp up to try that...i never even got a chance to turn it up...when i cranked the master, the amp made a weird noise and stopped working...the power was still on so no blown fuse...but no sound...and you could smell smoke...i have NO clue about repairs and whatnot..i just play..i've obviously gotta take it to get fixed but i am worried it's gonna be expensive..i don't think the seller sent me a broken amp because it worked at first..but i don't know to go about this..i love the tone so i don't wanna send the amp back...however, i don't wanna suck up the cost of repairs (if it's alot)

my friend Dale thinks the tubes were bad and i fried them when i cranked the master and that probably blew a resistor...he said it's probably not a hard fix and that the tung sol el34's in my amp arent what i need anyways....he said i would like Ruby el34's biased to between 30 and 35ma per tube based on the fact i'm gonna keep the master around 10:00 to 11:00 and run the preamp accordingly.....any opinions would be greatly appreciated..i just want this issue fixed and pray it doesn't happen again because this amp is a beast!!

Procter2812 · 11-06-2009, 09:55 AM

Ahh not good dude! I have the stock 2203 RI and its sweet enough! Cant imagine what its like modded!

First thing, check the HT fuse.

If the Valves have gone the HT fuse should have blown.

The power light will still be on if the HT fuse has blown as the power light is powered off the mains supply after the Mains fuse.

Hope this helps!

solarburnDSL50 · 11-06-2009, 12:07 PM

Quote:

Originally Posted by AllSheWrote

yesterday, my fja modded 2203 reissue came in (has a heyboer transformer, depth mod and mid sweep mod)..i was so excited...got it from a reputable seller...turned it on and was in HEAVEN for the first 5 minutes...i started playing with the volumes...i had the preamp around 1:00 and master around 10:00 when i was loving it..that's normally how i run an amp....i turned the preamp way down and cranked the master..then started turning the preamp up to try that...i never even got a chance to turn it up...when i cranked the master, the amp made a weird noise and stopped working...the power was still on so no blown fuse...but no sound...and you could smell smoke...i have NO clue about repairs and whatnot..i just play..i've obviously gotta take it to get fixed but i am worried it's gonna be expensive..i don't think the seller sent me a broken amp because it worked at first..but i don't know to go about this..i love the tone so i don't wanna send the amp back...however, i don't wanna suck up the cost of repairs (if it's alot)

my friend Dale thinks the tubes were bad and i fried them when i cranked the master and that probably blew a resistor...he said it's probably not a hard fix and that the tung sol el34's in my amp arent what i need anyways....he said i would like Ruby el34's biased to between 30 and 35ma per tube based on the fact i'm gonna keep the master around 10:00 to 11:00 and run the preamp accordingly.....any opinions would be greatly appreciated..i just want this issue fixed and pray it doesn't happen again because this amp is a beast!!

I know you didn't buy the amp from FJA mods but you can call Jerry if needed and he will help. I would. It may have been a bad tube or something internal causing a tube to go if that's what happened. I bet its fixable without too much cost. If you want to keep it I'd get it looked at just in case whatever is wrong with it doesn't keep blow'n tubes.

Winged =C='s are prolly the most durable/reliable of current production power tubes. The Ruby BSTR's sound good to me as well but more for metal cause to me they are a tighter sounding power tube. I prefer the 6CA7EH's I have in now. JJ EL34L's were good too its just that it can be hit and miss from batch to batch with these. I did like the sound of them. Reliability can be bad though.

What you need to do is figure out what your plate voltage is and then bias your amp accordingly. Running your power tubes too hot will burn them out more quickly. Bias them at 70% plate dissipation and you will be fine running them at any volume.

I like to run mine from 65% to 70%.

Trick · 11-06-2009, 12:30 PM

Quote:

Originally Posted by AllSheWrote

i turned the preamp way down and cranked the master.

I think you just found your problem, What were you trying to amplify with no pre-amp volume????? I believe you'll find your problem might have been caused by that move. That just sounds......Backwards. I hope it is nothing major, that's a great amp!

solarburnDSL50 · 11-06-2009, 12:37 PM

Quote:

Originally Posted by Trick

I think you just found your problem, What were you trying to amplify with no pre-amp volume????? I believe you'll find your problem might have been caused by that move. That just sounds......Backwards. I hope it is nothing major, that's a great amp!

I do this as well to bring in more power tube when I'm doing low to midgain stuff and want to get out of the preamp fizz. Won't hurt a thing.

Trick · 11-07-2009, 04:46 PM

Quote:

Originally Posted by solarburnDSL50

I do this as well to bring in more power tube when I'm doing low to midgain stuff and want to get out of the preamp fizz. Won't hurt a thing.

On a 2203???

Procter2812 · 11-07-2009, 05:28 PM

Quote:

Originally Posted by Trick

On a 2203???

I dont think it will... It might do if you have it biased at Marshall's specs!

70% is a good number for power valves. Its the standard setting generally... any hotter and the valves are gonna cook and will shorten their life span.

Using the master cranked way up with the pre-amp down, and with 90mv bias on the power valves is gonna be real hard on these CP valves.

Tung-Sol are not known for handling high voltages in these amps. The 800 has a high plate voltage anyway.

ironlung40 · 11-07-2009, 05:40 PM

What can you hurt by cranking the master wide open and then adjusting the preamp volume? I say absolutely nothing. This is a very common way of dialing in an amp. I do it all the time on my 2203. You will not hurt your amp running the master fully open, trust me. Now, on the other hand you are stressing your tubes, so you'll shorten their life a bit. Just make sure the amp is biased correctly and then you can play it as loud and hard as you want.

It sounds to me like a tube may have been bad, and probably a relatively cheap fix. I say have the amp checked out and fixed. I don't see how you can hold the seller to anything in this situation as it was working when you got it, so long as there is no evidence that he hid any info on the amp. this is the way buying used turns out sometimes.

Jesstaa · 11-07-2009, 05:47 PM

This happened to me, but one of my tubes actually caught fire. I did basically the exact thing on my 900. But it only didn't blow the mains fuse cause the previous owner had bypassed the fuse.

Procter2812 · 11-07-2009, 06:12 PM

Quote:

Originally Posted by Jesstaa

This happened to me, but one of my tubes actually caught fire. I did basically the exact thing on my 900. But it only didn't blow the mains fuse cause the previous owner had bypassed the fuse.

WOW

find em and kill em!

Thats like probably fucked your amp big time!

MajorNut1967 · 11-07-2009, 06:24 PM

You guys are approaching this in a three stooges manner! first stop turning the amp on after you had an issue. Second if you want to know what fried, pull the chassis out and look don't touch! If you see obvious burnt parts or smell that distinct burnt transformer smell take it to a qualified tech or call jerry as solar said.

Richman1 · 11-08-2009, 06:14 AM

Quote:

Originally Posted by MajorNut1967

You guys are approaching this in a three stooges manner! first stop turning the amp on after you had an issue. Second if you want to know what fried, pull the chassis out and look don't touch! If you see obvious burnt parts or smell that distinct burnt transformer smell take it to a qualified tech or call jerry as solar said.

Majornut is correct....When you can smell that burned electronics smell....don't do anything at all but get it to a repair shop before something worst happens to it. obviously you cooked something more than just a tube or a fuse...

AllSheWrote · 11-13-2009, 11:07 PM

Quote:

Originally Posted by Richman1

Majornut is correct....When you can smell that burned electronics smell....don't do anything at all but get it to a repair shop before something worst happens to it. obviously you cooked something more than just a tube or a fuse...

you are right..it ended up burning up like 5 or 6 things inside the amp...it was bad...what's crazy though is now that's it's fixed, it actually sounds even better then when i first heard it and loved it..that first night before it messed up, i had feedback..nothing terrible..but enough to where i figured i'd buy a noise gate....now, NO feedback...the tech i go to is REALLY good...in fact, Jerry at fja (who now i consider one of the nicest guys on earth) spent alot of time talking to my tech and going over stuff with him...he didn't have to do that and he was happy to....my tech said it was a bad tube and something to do with a heater pot or something that sounds like that (i just play..i i don't repair..lol)...none the less, he replaced the tubes with the mullard reissues..i loved them in my splawn quickrod so i wanted to go with them in the marshall...they sound incredible...this amp is honestly my dream tone...it sounds huge!...the depth and mid sweep mod is absolute heaven..i can pretty much dial everything on the amp flat (except the never turn the master past 10:00...sooooo loud!)...and i can adjust the mid sweep and depth knobs to make adjustments..it just really sounds incredible....i highly suggest looking into FJA mods if you ever wanna mod your amp...his work speaks for itself and his personality is out of this world...now i just pray it continues to work

solarburnDSL50 · 11-13-2009, 11:30 PM

Quote:

Originally Posted by AllSheWrote

you are right..it ended up burning up like 5 or 6 things inside the amp...it was bad...what's crazy though is now that's it's fixed, it actually sounds even better then when i first heard it and loved it..that first night before it messed up, i had feedback..nothing terrible..but enough to where i figured i'd buy a noise gate....now, NO feedback...the tech i go to is REALLY good...in fact, Jerry at fja (who now i consider one of the nicest guys on earth) spent alot of time talking to my tech and going over stuff with him...he didn't have to do that and he was happy to....my tech said it was a bad tube and something to do with a heater pot or something that sounds like that (i just play..i i don't repair..lol)...none the less, he replaced the tubes with the mullard reissues..i loved them in my splawn quickrod so i wanted to go with them in the marshall...they sound incredible...this amp is honestly my dream tone...it sounds huge!...the depth and mid sweep mod is absolute heaven..i can pretty much dial everything on the amp flat (except the never turn the master past 10:00...sooooo loud!)...and i can adjust the mid sweep and depth knobs to make adjustments..it just really sounds incredible....i highly suggest looking into FJA mods if you ever wanna mod your amp...his work speaks for itself and his personality is out of this world...now i just pray it continues to work

Congrats! Jerry's a good guy and knows his stuff. He recommends the Mullard RI EL34's in the Marshall's too.

AllSheWrote · 11-13-2009, 11:46 PM

yeah man..Jerry is the real deal...not to beat a dead horse but he really went out of his way offering his help...my tech was even shocked that jerry was doing that...my tech said he could have done the work no problem but when jerry called him and started talking about stuff, he was able to do the job alot faster...not that there was any guess work..but still...jerry just really knew exactly what was going on and how to go about fixing it the best way

Trick · 11-14-2009, 05:33 PM

Quote:

Originally Posted by MajorNut1967

You guys are approaching this in a three stooges manner!

Moe, Larry, Cheese!

11-06-2009, 08:53 AM	#1 (permalink)
AllSheWrote Junior Member Join Date: Nov 2009 Location: Fayetteville, NC Posts: 5	my jcm800 modded 2203 died last night..help yesterday, my fja modded 2203 reissue came in (has a heyboer transformer, depth mod and mid sweep mod)..i was so excited...got it from a reputable seller...turned it on and was in HEAVEN for the first 5 minutes...i started playing with the volumes...i had the preamp around 1:00 and master around 10:00 when i was loving it..that's normally how i run an amp....i turned the preamp way down and cranked the master..then started turning the preamp up to try that...i never even got a chance to turn it up...when i cranked the master, the amp made a weird noise and stopped working...the power was still on so no blown fuse...but no sound...and you could smell smoke...i have NO clue about repairs and whatnot..i just play..i've obviously gotta take it to get fixed but i am worried it's gonna be expensive..i don't think the seller sent me a broken amp because it worked at first..but i don't know to go about this..i love the tone so i don't wanna send the amp back...however, i don't wanna suck up the cost of repairs (if it's alot) my friend Dale thinks the tubes were bad and i fried them when i cranked the master and that probably blew a resistor...he said it's probably not a hard fix and that the tung sol el34's in my amp arent what i need anyways....he said i would like Ruby el34's biased to between 30 and 35ma per tube based on the fact i'm gonna keep the master around 10:00 to 11:00 and run the preamp accordingly.....any opinions would be greatly appreciated..i just want this issue fixed and pray it doesn't happen again because this amp is a beast!!

11-06-2009, 09:55 AM	#2 (permalink)
Procter2812 Senior Member Join Date: Mar 2009 Posts: 333	Re: my jcm800 modded 2203 died last night..help Ahh not good dude! I have the stock 2203 RI and its sweet enough! Cant imagine what its like modded! First thing, check the HT fuse. If the Valves have gone the HT fuse should have blown. The power light will still be on if the HT fuse has blown as the power light is powered off the mains supply after the Mains fuse. Hope this helps! __________________ www.sexpistolstribute.co.uk JCM800 2203X JCM2000 TSL100 Marshall 1936 Gibson Les Paul Custom Orville Les Paul Custom Fender Highway One Stratocaster Boss EQ Ibanez Tube Screamer Crybaby Wah Boss TU-2

11-07-2009, 05:40 PM	#8 (permalink)
ironlung40 Senior Member Join Date: Nov 2008 Location: Maryville, TN Posts: 309	Re: my jcm800 modded 2203 died last night..help What can you hurt by cranking the master wide open and then adjusting the preamp volume? I say absolutely nothing. This is a very common way of dialing in an amp. I do it all the time on my 2203. You will not hurt your amp running the master fully open, trust me. Now, on the other hand you are stressing your tubes, so you'll shorten their life a bit. Just make sure the amp is biased correctly and then you can play it as loud and hard as you want. It sounds to me like a tube may have been bad, and probably a relatively cheap fix. I say have the amp checked out and fixed. I don't see how you can hold the seller to anything in this situation as it was working when you got it, so long as there is no evidence that he hid any info on the amp. this is the way buying used turns out sometimes.

11-07-2009, 05:47 PM	#9 (permalink)
Jesstaa Senior Member Join Date: Apr 2009 Location: Gippsland, Vic, Australia. Posts: 797	Re: my jcm800 modded 2203 died last night..help This happened to me, but one of my tubes actually caught fire. I did basically the exact thing on my 900. But it only didn't blow the mains fuse cause the previous owner had bypassed the fuse. __________________ GEAR LIST Marshall JCM900 4100 (6L6) (1995) Marshall Valvestate 1965A cab (????) Cort VX-2V (2008) TUBES/SPEAKERS Power: Groove Tube 6L6GCB Phase Inverter: Sovtek 7025 Pre: V1 - N.O.S Mullard ECC83. V2 National 12AX7A Speakers: Celestion G10L-35 Marshall forever My tube amp & Real Music appreciation forum

11-07-2009, 06:24 PM	#11 (permalink)
MajorNut1967 Senior Member Join Date: Jul 2009 Location: South Pacific Posts: 710	Re: my jcm800 modded 2203 died last night..help You guys are approaching this in a three stooges manner! first stop turning the amp on after you had an issue. Second if you want to know what fried, pull the chassis out and look don't touch! If you see obvious burnt parts or smell that distinct burnt transformer smell take it to a qualified tech or call jerry as solar said. __________________ MJN1967 aka BA (Bad Attitude) 1968 model 1987 50watt. A Baby Major (Half-Power) I built from the ground up. JTM 45 Clone combo Ground up build. JCM 800 Clone Ground up build. Custom Built Warmoth Strat 75' Fender Tele-Deluxe '70 style strat custom build w/Custom Shop 69's PU's

11-13-2009, 11:46 PM	#15 (permalink)
AllSheWrote Junior Member Join Date: Nov 2009 Location: Fayetteville, NC Posts: 5	Re: my jcm800 modded 2203 died last night..help yeah man..Jerry is the real deal...not to beat a dead horse but he really went out of his way offering his help...my tech was even shocked that jerry was doing that...my tech said he could have done the work no problem but when jerry called him and started talking about stuff, he was able to do the job alot faster...not that there was any guess work..but still...jerry just really knew exactly what was going on and how to go about fixing it the best way __________________ formerly of "He Is Legend" current band "Memphis Witch" FJA modded jcm800 2203x (heyboer transformer, extra gain stage, depth and mid sweep mods) Mesa 4x12 traditional ESP ec400at goldtop Gibson usa explorer

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