LSC problem

[king.bee]

Hey. rookie here and this is my first post!!

i bought my LSC about 18months ago and i've had an intermittant problem with it since.

the problem is that you can be playing the amp fine then half way through the rehearsal/gig, the output from the amp can just die completely or you get a severly brokend output. at first i thought it was related to the footswitch but i switched that out and i still got the same problem. then i thought it was a scratchy pot someplace so i had them all cleaned.

i run nothing in the effects loop, i've checked all external sources (cables, pedals etc) and they're fine too.

I've had the amp to the UK main amp tech for boogie (dennis marshall) and he couldn't find anything wrong aside from a couple of near dry joints. he ran the amp for over 3 hours solid at varying voltages and never came across the problem.

do any of you guys have any suggestions?

 

[boogiemon]

Same thing happened to me a couple days ago. i thought it was the EL34's so i put in some 6L6's & was ok for the rest of the session but i later plugged the El34's into a tube tester & they all checked out fine. i too have nothing plugged into the effects loop. What type of power tubes are you using?

Hey. rookie here and this is my first post!!

i bought my LSC about 18months ago and i've had an intermittant problem with it since.

the problem is that you can be playing the amp fine then half way through the rehearsal/gig, the output from the amp can just die completely or you get a severly brokend output. at first i thought it was related to the footswitch but i switched that out and i still got the same problem. then i thought it was a scratchy pot someplace so i had them all cleaned.

i run nothing in the effects loop, i've checked all external sources (cables, pedals etc) and they're fine too.

I've had the amp to the UK main amp tech for boogie (dennis marshall) and he couldn't find anything wrong aside from a couple of near dry joints. he ran the amp for over 3 hours solid at varying voltages and never came across the problem.

do any of you guys have any suggestions?

 

[fishyfishfish]

Try a short patch cord in the loop send and return, and see if that fixes the problem.

 

[boogiemon]

That's a good suggestion. The other test would be to simply switch the effects loop out of the circuit.

Try a short patch cord in the loop send and return, and see if that fixes the problem.

 

[king.bee]

thanks for the tip. i'll try it.

re power tubes: i'm still using the standard issue boogie ones that came with the amp.

 

[ama_kid]

King.bee -

Check the forum below:

http://forum.grailtone.com/viewtopic.php?t=24173

This thread was related to the issues I had with my LSC, which at this time has yet to be resolved. My LSC is currently at Mesa and they have yet to find a resolution. We tried a set of new power tubes, new preamp tubes and a new rectifier tube. They have at this point narrowed it down to an issue with my Drive circuit.

A couple quick questions. Is this happening on both channels? Tweed Setting as will as full power? With the Drive Circuit engaged on Channel 2? Rectifier Tracking or Silcon Diodes?

Good luck! I've had a hell of a time with mine, but when it worked right, it was absolutely amazing!!

 

[king.bee]

King.bee -

Check the forum below:

http://forum.grailtone.com/viewtopic.php?t=24173

This thread was related to the issues I had with my LSC, which at this time has yet to be resolved. My LSC is currently at Mesa and they have yet to find a resolution. We tried a set of new power tubes, new preamp tubes and a new rectifier tube. They have at this point narrowed it down to an issue with my Drive circuit.

A couple quick questions. Is this happening on both channels? Tweed Setting as will as full power? With the Drive Circuit engaged on Channel 2? Rectifier Tracking or Silcon Diodes?

Good luck! I've had a hell of a time with mine, but when it worked right, it was absolutely amazing!!

thanks for the link.

yip, its happening on both channels, both power settings and on tracking or diodes.

will be interested to hear what's up with your if they ever sort it out.

 

[ama_kid]

Sorry to be the bearer of bad news, but I got my LSC back from Mesa yesterday and it still wasn't completely right. Its been a 6 month saga of issues from start to finish.

Mesa narrowed my issue down to a broken circuit in the channel 2 drive switch and a full replacement of all power tubes and 1 power tube socket. Sadly, the footswitch issue (didn't mention in my last post) on mine was still there. On the bright side, I got my cash back and applied it to the '07 LSC they had at $600 less than what I paid for the other one!! Tested it out for about 2 hours with no issues and multiple guitars. Sounds so good!

What I would recommend, and depending on your location, is to get it into Mesa or a Mesa Authorized Technician so they can do a once over. Should still be covered under warranty. I wouldn't want anyone to go through what I had been for the last 6 months (4 times to GC's amp tech, then to Mesa for 2 months, no MAT's around me 'cause Mesa is about 1 1/2 hours from me).

Definitely look into replacing those power tubes. Doug's Tubes or EuroTubes will defintely help you out on suitable replacements. Good luck!

 

[king.bee]

so just thought i'd update on my LSC problem.

turns out the problem lay with the return jack of the loop. the story goes that for a period of time, boogie had a problem with the supplier of their jack sockets so they outsourced to a company who supplied inferior substitutes. (that's what my LSC had). these sockets are reknowned for 'letting go' early in their career.

anyway, both have been replaced with cliff jacks and the LSC is back to full working order. WOOP!

out of interest: i will also be working on a little special mod of my own in the next couple of weeks. if it works out, i'll post up the steps to follow for those interested.

B.

 

[plan-x]

Great news on your fix and good info for future reference. Mod? do say.

 

[djw]

out of interest: i will also be working on a little special mod of my own in the next couple of weeks. if it works out, i'll post up the steps to follow for those interested.

I second plan-x's interest in this. Aren't we a meddlesome bunch? Can't seem to leave well enough alone.

Glad you got that problem sorted out.

 

[king.bee]

cheers chaps.

i should be testing the mod next week. i'll keep you on tender hooks until i've A/b'd the mod and let you know if it's worth while.

its such a little change but could have a BIG effect. :wink:

 

[thirstypirate]

turns out the problem lay with the return jack of the loop. the story goes that for a period of time, boogie had a problem with the supplier of their jack sockets so they outsourced to a company who supplied inferior substitutes. (that's what my LSC had). these sockets are reknowned for 'letting go' early in their career.

Welcome to the board B,

Could you post the serial number of your LSC so that we could see if ours are in the vicinity of the ones with crappy jacks. Thanks.

Good luck with the mod. I can't wait to hear about it.

 

[plan-x]

Ok, the suspence is killing me. I wonder if the mod has something to do with the loop, since King.bee is already upgrading that area? Hmm, just speculating. since the LSC threads have slowed down as of late. :wink:

 

[Bill11]

turns out the problem lay with the return jack of the loop...these sockets are reknowned for 'letting go' early in their career.

i will also be working on a little special mod of my own in the next couple of weeks. if it works out, i'll post up the steps to follow for those interested.

B.

Hi king.bee,

Thank you for the update on what you found; this is good to know.

And if you could post information about the serial number series that had these loop jack problems that would be great. If you are comfortable, you could just post the first digits of the amp serial number and mask that last two or three digits with x's to protect its identity.

And I would like to hear more about your mod, too; whether it works or not!