Jump to content
Sign in to follow this  
Prehistoricpain

Amp turns on, no sound,tubes wont light up.

Recommended Posts

Blown fuse?

 

Checked the fuse, looks fine. Tried all the speaker outs, different cords, different cabs. Nothin'. I had this same amp working, great last week and then this practice it just wont light a single tube, not even the preamp tubes. :facepalm:

Share this post


Link to post
Share on other sites

Change power tubes, replace fuse. Check again.

 

Careful, this can be a really quick way to blow a new set of tubes if you don't know what fried the fuse.

Share this post


Link to post
Share on other sites

Careful, this can be a really quick way to blow a new set of tubes if you don't know what fried the fuse.

 

And I really don't see why the preamp tubes wouldn't light up if the power tubes were shot.. Would they?

Share this post


Link to post
Share on other sites

And I really don't see why the preamp tubes wouldn't light up if the power tubes were shot.. Would they?

 

I'd wait for someone more qualified to answer, but in my experience, when tubes or anything else goes awry, the preamp tubes tend not to light up either. Do you have another amp you can put the VTM's tubes in to see if the power tubes are shot? If the fuse looks fine, it very well might be them.

Share this post


Link to post
Share on other sites

I'd wait for someone more qualified to answer, but in my experience, when tubes or anything else goes awry, the preamp tubes tend not to light up either. Do you have another amp you can put the VTM's tubes in to see if the power tubes are shot? If the fuse looks fine, it very well might be them.

 

They were the original peavey branded tubes.. soooooo.

Share this post


Link to post
Share on other sites

It could be so many things, it's kinda hard to just guess on a forum.

 

Test everything you can, the power cable, the socket you have the amp plugged into, the valves in a different amp, the fuses.. if you can't find anything it's time to take it to an amp repair guy who will probably know what's wrong with it in 10 mins.

Share this post


Link to post
Share on other sites

It could be so many things, it's kinda hard to just guess on a forum.


Test everything you can, the power cable, the socket you have the amp plugged into, the valves in a different amp, the fuses.. if you can't find anything it's time to take it to an amp repair guy who will probably know what's wrong with it in 10 mins.

 

Word, I just thought I would run it past you guys to see if you had any other ideas I hadn't already tried. Being broke sucks! :lol:

Share this post


Link to post
Share on other sites

This happened to my Peavey Delta Blues, flip the switch and the power light came on but not tube glow, and nothing worked, come to find out one of the tube plugs had shorted and fried my power transformer (no fuse protection on that side unfortunately) Could be a similar case here...

 

 

Phillip

Share this post


Link to post
Share on other sites

Word, I just thought I would run it past you guys to see if you had any other ideas I hadn't already tried. Being broke sucks!
:lol:

 

yeah, I hear you.... ok, forget about the valves for now...

 

is there a power light that should light up when you turn it on and is that dead too or does that light up?

Share this post


Link to post
Share on other sites

I had the same issue with a Peavey Triumph 120. I changed the fuse but it didn't help so I put new power tubes in and it worked fine after that.

Share this post


Link to post
Share on other sites

yeah, I hear you.... ok, forget about the valves for now...


is there a power light that should light up when you turn it on and is that dead too or does that light up?

 

The power and standby lights come on fine, so that seems normal. It was my impression that if a power transformer shits the bed, your amp would not get power to anything, not just the tubes.

Share this post


Link to post
Share on other sites

The power and standby lights come on fine, so that seems normal. It was my impression that if a power transformer shits the bed, your amp would not get power to anything, not just the tubes.

 

 

right, I would say tubes is a pretty good bet then to be honest. How old are they/how much use roughly? it might be getting towards the time for a full new set anyway.

Share this post


Link to post
Share on other sites

what if an amps cooling fan turns on but nothing else does? no standby light etc.....except the fan in the back?

 

is that a transformer most likely?

 

its a peavey classic 100 head

Share this post


Link to post
Share on other sites

I was speaking to an amp tech about the same problem (but in a different amp) just the other week. He said most often it's an internal fuse (ie not the one you'd normally check). I still play it safe when it comes to amps, messing with those can literally kill, even when unplugged, so take no risks ok?

 

I took my amp for a service just a couple of months ago, first time I've had an amp repaired, and I was actually really pleased at how affordable it was.

Share this post


Link to post
Share on other sites

right, I would say tubes is a pretty good bet then to be honest. How old are they/how much use roughly? it might be getting towards the time for a full new set anyway.

 

It looks like they are the original tubes, this is a mid 80s It looks like peavey VTM. I'll take a look and see if I can find any internal fuses that have blown, although if it had, I would assume it was from another problem, like say bad tubes.

Share this post


Link to post
Share on other sites

If the tubes aren't lighting up then there's a problem with the heater filament voltage supply. Some amps have an additional fuse on the filament supply. This amp may have one and it may be only internally accessible. I couldn't find a schematic or any internal pictures to find out.

 

Edit: I found a schematic. The filament supply does have a fuse, labelled 'F4'. That would be the first thing I would check.

 

Then, if the fuse is blown and blows again after being replaced then you, or better yet a tech, need to determine why it blew.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

×
×
  • Create New...