#1
Alright, so I was playing with my amp (Cratev-50) and then my amp stopped making any sound, switched the cables, and still nothing.

The power tubes were glowing so I guess that means I need new pre-amp tubes?

what are some good pre amp tubes I should get? How much will it cost? do pre-amp tubes need to biased too?
#2
Wow. That seems odd. If you've checked everything else including guitar volume then I suppose it could be preamp tubes. Just for kicks, can you try a different guitar in the amp or your guitar in a different amp?

Preamp tubes are usually about $10-$20 each. You probably have 12AX7s. I would look up the specs for your amp, go online like to a tubedepot.com and get new ones. No they don't need to be biased and yes there are tutorials on youtube and the like on how to swap them out. Should be a piece of cake.
#5
yes, that does sound indicative of a preamp problem.

you can take a pencil and gently push/nudge/tap the preamp tubes with the eraser end and see if you can hear it coming thru the speaker. You may only need to buy 1.

ps. Power tubes are glowing normally right, lightly? Not super bright or anything?
#6
Quote by 311ZOSOVHJH
yes, that does sound indicative of a preamp problem.

you can take a pencil and gently push/nudge/tap the preamp tubes with the eraser end and see if you can hear it coming thru the speaker. You may only need to buy 1.

ps. Power tubes are glowing normally right, lightly? Not super bright or anything?


They don't seem to be glowing differently.

Do I push them with the pencil while the amp is on standby? or do I take the standy off and put it on?
#7
Maybe you popped a fuse?

Just because the power tubes are glowing doesn't mean they are working. The part that glows is just the heater filament.
#8
^good point

I guess I assumed that if the HT fuse blew there would be no power to the power tubes. Al is smarter than I on this stuff so listen to him.


yes, off standby as if you were playing thru amp, vol up. Is the amps light on? Can you hear a hum or anything? You will probably have to take those aluminum casings off to access preamp tube.
#10
what do you mean, you only have the problem on clean or can here your pencil tapping only on clean or what?

was your amp new or used?
3 preamp tubes right?

they are real easy to swap, you can always run to GC or the like and buy 1 and then swap it thru until you find problem. That is if it even is a preamp tube problem, but it's a cheap way to check if unsure.
#11
I've got 5 dollars on a preamp tube problem.

Takers?
#12
Quote by 311ZOSOVHJH
what do you mean, you only have the problem on clean or can here your pencil tapping only on clean or what?

was your amp new or used?
3 preamp tubes right?

they are real easy to swap, you can always run to GC or the like and buy 1 and then swap it thru until you find problem. That is if it even is a preamp tube problem, but it's a cheap way to check if unsure.


bought it new.
I can hear a buzz when the amp is on the clean channel (without doing anything)
but when I switch to the OD channel it's 100% quiet