DSL 50 just shuts off randomly! Please help!

Heavy Ed · 09-23-2009, 11:53 AM

Well I've had my (used) DSL 50 for about 5 months now. I did a complete retube and bias when I got it and it was fantastic. All of a sudden last week during rehearsal it died. No sound, no power, no lights, nothing! I shut it off and waited a few minutes. I didn't smell anything burning, tubes were fine checked the fuses they were good too. I changed my power strip, fired it back up and played the rest of the night without incident. Now last night at practice 3 songs in the power light/switch started flashing then went out. No sound etc, etc.. I opened up the chassis and could see nothing out of the ordinary. Nothing burnt or charred, nothing broken or loose. I put it back together plugged it in turned it on and the on/off switch was flashing again. shut it off turned it on the light stayed constant. I'm at a loss any suggestions? I want to take it to a tech but can't find any that are reputable in my area! Any info would be a great help. Thanx fellas!

American Viking · 09-23-2009, 03:14 PM

That's a failsafe to keep the amp alive. You have an unmatched load on the amplifier. You have to correctly match the impedance from your amplifier to your speaker cab. Older amps will blow fuses or blow transformers altogether. Continuing to try to use your amp in a situation like this will ultimately destroy it. Correct the problem then try again.

The first post in this thread explains impedance matching. I can answer any more questions you may have.
Amp problems? Ohm questions? Amp blowing up for no reason, READ ME!

Also make sure you are using a proper speaker cable and not an instrument cable to connect to your cabinet.

Ken · 09-23-2009, 03:42 PM

Just an idea, but try changing the fuses. It's easy to do at least!

If that doesn't work, try playing through a different spaker cabinet with different patch cords which address the issue Viking said. If you have a blown speaker it will definitely screw up the impedence! Oh, make sure the selector switch didn't somehow get shoved on to the wrong setting too!

If that doesn't work, I suppose you need a tech guy to look at it.

Ken

Heavy Ed · 09-23-2009, 08:10 PM

Quote:

Originally Posted by American Viking

That's a failsafe to keep the amp alive. You have an unmatched load on the amplifier. You have to correctly match the impedance from your amplifier to your speaker cab. Older amps will blow fuses or blow transformers altogether. Continuing to try to use your amp in a situation like this will ultimately destroy it. Correct the problem then try again.

The first post in this thread explains impedance matching. I can answer any more questions you may have.
Amp problems? Ohm questions? Amp blowing up for no reason, READ ME!

Also make sure you are using a proper speaker cable and not an instrument cable to connect to your cabinet.

Ummm... no I have correct impedance 8 ohm cab, DSL set to 8 ohms I have a heavy duty SPEAKER cable not just an instrument cable and I 've been running in this way for 5 Months! The trouble just started last week. When it shut off everything goes out lights, tubes, everything, there is no power what so ever its not powering down its dead. The only possibility of ohm mismatch is if I blew a speaker which I will check tommorow. Any other suggestions?

Sir Don · 09-23-2009, 08:17 PM

Cold solder joint on your power switch maybe.

T-Bird · 09-24-2009, 01:02 AM

Hi.

Quote:

Originally Posted by Sir Don

Cold solder joint on your power switch maybe.

Or a crapped out switch.

I'd check that next.

Regards
Sam

American Viking · 09-24-2009, 01:58 AM

Quote:

Originally Posted by Heavy Ed

Ummm... no I have correct impedance 8 ohm cab, DSL set to 8 ohms I have a heavy duty SPEAKER cable not just an instrument cable and I 've been running in this way for 5 Months! The trouble just started last week. When it shut off everything goes out lights, tubes, everything, there is no power what so ever its not powering down its dead. The only possibility of ohm mismatch is if I blew a speaker which I will check tommorow. Any other suggestions?

You could be matching your impedance properly, but like you said, if a speaker within the cab is blown it will throw the impedance off causing a mismatch, ultimately resulting in your amp shutting down. I only know this from learning the hard way.

That's what my DSL100 did when I had a speaker fail within a cab and I didn't notice immediately.

Other than that I cannot think of anything right off the top of my head that could result in the amp shutting off. One thing I would suggest to anyone is that it's never a bad idea to have a spare set of tubes to swap out in this situation, just to eliminate a suspect if nothing else.

Let us know what you find out.

Heavy Ed · 09-24-2009, 07:26 PM

Well i checked the cab and all speakers are working properly. I was planning on sending my DSL to FJA for a mod, might as well have him look at this too!

09-23-2009, 11:53 AM	#1 (permalink)
Heavy Ed Member Join Date: May 2009 Location: Pennsyltucky Posts: 45	DSL 50 just shuts off randomly! Please help! Well I've had my (used) DSL 50 for about 5 months now. I did a complete retube and bias when I got it and it was fantastic. All of a sudden last week during rehearsal it died. No sound, no power, no lights, nothing! I shut it off and waited a few minutes. I didn't smell anything burning, tubes were fine checked the fuses they were good too. I changed my power strip, fired it back up and played the rest of the night without incident. Now last night at practice 3 songs in the power light/switch started flashing then went out. No sound etc, etc.. I opened up the chassis and could see nothing out of the ordinary. Nothing burnt or charred, nothing broken or loose. I put it back together plugged it in turned it on and the on/off switch was flashing again. shut it off turned it on the light stayed constant. I'm at a loss any suggestions? I want to take it to a tech but can't find any that are reputable in my area! Any info would be a great help. Thanx fellas! __________________ 96' & 97' Ibanez UV7bks Splawn 06' Quickrod Marshall DSL50 Marshall Mode Four Mode Four Cab w/GK-100s

09-23-2009, 03:14 PM	#2 (permalink)
American Viking Senior Member Join Date: Jan 2009 Location: RICHMOND, VIRGINIA Posts: 2,031	Re: DSL 50 just shuts off randomly! Please help! That's a failsafe to keep the amp alive. You have an unmatched load on the amplifier. You have to correctly match the impedance from your amplifier to your speaker cab. Older amps will blow fuses or blow transformers altogether. Continuing to try to use your amp in a situation like this will ultimately destroy it. Correct the problem then try again. The first post in this thread explains impedance matching. I can answer any more questions you may have. Amp problems? Ohm questions? Amp blowing up for no reason, READ ME! Also make sure you are using a proper speaker cable and not an instrument cable to connect to your cabinet. __________________ Transformers inside amplifiers were not originally designed to be in there, and the tube was not created for the guitar amp. ANY recommended idle current is a guideline and in no way a necessary requirement. There is no skeleton key for any tube amp.

09-23-2009, 03:42 PM	#3 (permalink)
Ken Senior Member Join Date: Feb 2009 Location: Arlington Heights, IL Posts: 1,165	Re: DSL 50 just shuts off randomly! Please help! Just an idea, but try changing the fuses. It's easy to do at least! If that doesn't work, try playing through a different spaker cabinet with different patch cords which address the issue Viking said. If you have a blown speaker it will definitely screw up the impedence! Oh, make sure the selector switch didn't somehow get shoved on to the wrong setting too! If that doesn't work, I suppose you need a tech guy to look at it. Ken

09-23-2009, 08:17 PM	#5 (permalink)
Sir Don Senior Member Join Date: Aug 2009 Location: Adelaide, South Australia Posts: 200	Re: DSL 50 just shuts off randomly! Please help! Cold solder joint on your power switch maybe. __________________ My gear: 2204, 2210, 2555, 9005, 1959, 5005, 4103, 2100, TSL100 www.myspace.com/rockthebosss

09-24-2009, 07:26 PM	#8 (permalink)
Heavy Ed Member Join Date: May 2009 Location: Pennsyltucky Posts: 45	Re: DSL 50 just shuts off randomly! Please help! Well i checked the cab and all speakers are working properly. I was planning on sending my DSL to FJA for a mod, might as well have him look at this too! __________________ 96' & 97' Ibanez UV7bks Splawn 06' Quickrod Marshall DSL50 Marshall Mode Four Mode Four Cab w/GK-100s

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