Marshall DSL 401 problem. Help needed!!

[Bryan]

Here's the deal. I have a Marshall DSL 401. All of a sudden it stops working. Lights come on, just no sound. I check the fuses everything looks good.

But here's the problem. The ohm switch on the back is switched to 8 ohms. But only the internal speaker is being used. The back panel says switch to 16 ohms for just the internal speaker.

So how bad is this???

This is my first tube amp and between this and the microphonic preamp tube that came with it (this is an ebay purchase) I am not having a great time with these.

[Twisteramps]

Bryan, that shouldn't be a big deal... but those amps were plagued with poor solder joints and a few other issues. Are the tubes lighting up and getting hot? Also, how did you check the fuses - visually or by putting a meter on there? Because a blown fuse can LOOK good.

Pete

[Bryan]

I don't have a meter. All the tubes are lighting up. I just visually id'ed the fuses and they look OK. Should I just go ahead and replace the fuses?

[jgcable]

If the lights are on and the tubes are glowing you might want to check the speaker cable. I doubt you have a bad fuse. Check the standby switch.

[GodWentPUNK]

I agree that if you have lights/tubes power your fuse is most likely good. Are you able to hook-up another cab to your external jack to see if you get anything?

joe...

[Bryan]

I ran the standby switch in both positions but no change. I'll see if I can hook up the amp to my Fender Deluxe Reverb speaker.

Funny thing is, it went out while I was playing. One second sound, next kaput.

[Twisteramps]

You can have a blown fuse, no sound and lit tubes. I'd try replacing fuses next - you should be able to find what you need at radio shack. Just make sure you replace the fuses with the same values and type.

Pete

[GodWentPUNK]

Pete: Then is the fuse powering like the power amp portion of the amp? I always thought on amps that the fuse was used to cut power off to the entire amp because something was wrong. You are the expert so maybe you can explain a little more.

thanks!

joe...

[Twisteramps]

An amp can have more than one fuse in it. Some amps have two that are accessable from the outside of the amp like an SLO. Some have one on the outside, and/or one (or more) on the PCB. Just depends on the amp. If you blow the right fuse, your amp will power up, but it will act like it's on permanent standby. The heaters are working but the high voltage isn't.

Pete

[markD]

this happened on one of my rivera's. the fuse on the back was okay, but the fuse on the PCB was blown so the amp powered up and everything, but there was no sound. i had to remove the chasis before i even knew there was a fuse on the PCB. once i replaced it, everything was peachy keen!!!

[Bryan]

Whew! Problem solved. It ended up being the fuse in the back. All is well and up and running. Thanks for all your help.

[GodWentPUNK]

Cool that you got it running. I have only 1 spare fuse which is for the main circut. I guess I should open up my amp and see if there is another to worry about.

joe...

[JACKSONFREAK]

G;ad ya got it workin. I was about to post that Marhsalls have 2 fuses on the back of the amp chassis. Onefor the power (electrical) of the amp And the other for the ouput to the speaker. But since ya got it fixed i wont. :P
Gil

[Twisteramps]

Gil - the 2nd fuse isn't for output to speaker. Typically one fuse is for high voltage B+, other is for the heaters.

Pete

[Bryan]

It was the 400mah (?) fuse that was blown. Anyways I'm glad that's over.

Although this may seem strange, but I really found myself not missing the Marshall that much. I began to really start liking my BK Tube Driver - Modded Fuzz Face - Fender Deluxe Reverb signal chain for distortion. Before that I went straight to the Marshall and would occasionally use the Tube Driver to kick the Marshall over the top. I'm really beginning to question the whole amp switching thing....