Blew out my Crate??

[davesellshouses]

I have a Crate VC5212B tube amp, approximately 10 yrs old. A few months ago someone at a pro-audio shop told me I could run my mixing board through my amp. They told me to keep the amp volume near zero, and use the volume controls on my mixing board. Well, I plugged it in, turned it on, here a millisecond of feedback, and then silence. The amp seems completely dead. I've looked at all of the tubes, and they appear to be ok. I can't find anything that looks like a fuse.
I'd appreciate any ideas anyone has about what I should look for.

Dave

[Gtr_tech]

They told you you could unplug the speaker and hook the speaker out into a mixer?? Or plug the mixer into the amp input? Either way its a retarded idea.....

[davesellshouses]

They told you you could unplug the speaker and hook the speaker out into a mixer?? Or plug the mixer into the amp input? Either way its a retarded idea.....

Hmmm....guess I'm not sure why you responded this way? I was hoping to get some direction on how I might fix my amp. I wasn't looking for a condesending insult.
Indy Pro Audio told me I could plug my mixer directly into the input of the amp...and I did what they suggested. You sir, know MUCH more about amplifiers than I ever will...that's why I came here for help. Too bad my first response came from an ass. Thanks for all of your terrific advice! I'll terminate my account immediately and find another place where perhaps I might get a mature professional who can offer the advice I'd asked for.

[Jazz P Bass]

You may have had a coincidental amp failure.
I do not see why the mixer would "blow up" your amp.
I do disagree with "run the amp low, mixer high"
A mixer can put out a pretty high signal voltage compared to a guitar.
That is a sound issue, not an amp function issue.

Do the front panel lights work?
Do the tubes "light up".

[Kazooman]

Hard to believe that there is no fuse. Check the rear panel again for a fuse holder. It is possible that they have the fuse buried inside to keep anyone from messing with it. If so you would have to remove the chassis to get to it. Be careful!! High voltages in there even long after the amp has been turned off.

I tried to find a schematic on the Internet without any luck. The Crate website has a link to a pdf version of the manual, but that link just takes you to their current products page.

Do you have a copy of the manual? If so, posting a copy of the schematic (if they gave you one) and any picture of the rear panel might help.

[telecaster]

On the Crate Vintage Club amps, take off the back panel and there should be a mains power supply fuse at the bottom left of the board, and then one for the B+ supply to the power tubes over to the right a bit. If the tubes are lighting up but there is no sound, it's possible the B+ fuse is blown. Please follow all the safety precautions FIRST before you check or touch anything - make sure the amp is unplugged, make sure the power supply caps are drained, use insulated handle tool to remove/replace the fuse, etc. The value for each of the fuses should be written on the board.

[Gtr_tech]

I responded that way 'cause its a stupid thing to do. Mixers are *line level* devices. Know what happens when you plug a line level output into a guitar level input? Distortion....and lots of it. Plus, guitar amps are not mixdown monitors. Thy are bandwidth limited right down to the speaker(s)....so it would never sound right. Use them for what they are for....playing a guitar thru.

Maybe you were trying to do the "reamp" thing? I dunno....you didn't specify. A channel strip insert would likely be too hot. You'd have to use an aux send and keep the level *way* low.

Don't be so thin skinned....this is the internet.....

[olddawg]

I would check the fuses and then the power transformer. My guess is that you got a reversed ground reference and opened a fuse or you pumped so much gain into the input that it drew maximum current from the power supply and popped a fuse or opened a transfomer with the surge. Coincidental failure is not uncommon. Especially if something is under/overfused or some component is on the verge of failure. BTW, I have run a mixer into a instrument amp many times. You might get a little noise floor problem but if you start with the gains down (especially whatever master volume on the board that you are using) and bring things up incrementaly it shouldn't be a problem, certainly not retarded. In electronics, especially in 10 year old tube amps, and certainly with a Crate, anything can fail at anytime. It's best if you know how to use a multimeter.