tube question

[yoursensesdrown]

hey guys im new here and dont know to much about internals of a mesa. Recently i noticed that one of my back tubes is out and i know i need to replace it. it is a 6l6gc mesa 430 tube i beleive. And i think i have another problem that may or may not be related to the blown tube. but when i have my amp turned on and i do not play i turn the volume up even when on a low gain and i get a horrible noise that kinda sounds like the ocean is inside of my amp!!!! its bugging the **** out of me. i also noticed that when i mute any cord and have the gain turned up to about 1:00 it starts to crackle as it fades out. does anyone know what i should do about this. should i send it to mesa???? should i jsut get new tubes???? i dunoo im lost. sorry for the noob comment but its just really getting to piss me off. let me know what you all think.

 

[domct203]

If you think you have a blown power tube STOP playing the amp. You can cause some damage to the amp if the tube shorts out. What do you mean by "recently i noticed that one of my back tubes was out"? Does the heater glow when the amp is on?

How old is the amp/tubes? The sounds you describe are typical of one or more bad pre-amp tubes (ocean sounds, crackle, etc.). You mention this happens even on low gain, but is it happening on all channels?

Be as descriptive as you can, this might just be a few bad tubes.

It would help to know what amp this is.

Dom

 

[yoursensesdrown]

first off its a triple rectifire 3 channel solo head and the tube is straight up out. i tried switching the tubes to see if the socket was blow but its just the 6l6 tube, no glow or anything its been out for about a month but i havent played it more than like 5 times. the amp is about almost 3 years old now. and yes it happens on all the channels. are the preamp tubes the el's or are they located inside the amp? sorry man ive been playing guitar for like 8 years but never learned any of the technical stuff. my brother worked in a local guitar shop and took care of things for me but now hes married and has a new job.

 

[yoursensesdrown]

oh yea and my fuse blew out the other day.

 

[domct203]

Thanks for more info.

Read your manual, it will tell you what tube goes where and what each type does.

The pre-amp tubes are the smaller tubes under the aluminum "cans" further back behind the power tubes. They are "12AX7" (or ECC83) type with nine pins. The "cans" have a spring inside that keeps the tubes seated. To remove the cans, gently turn them until they pop up, just hold them so they don't fly out of your hand. To remove a pre-amp tube gently rock the tube back and forth a little bit while pulling the tube straight up. If you take any tubes out be sure to make note of where the big space between the pins go, so you can line them back up with their sockets, and always put them back in the same position they came from. To put the cans back in, line up the bumps on the cans with the notches in the chassis around the tube, and gently press down and rotate to lock.

If you are running STR-430 6L6GC's then you should not have anything "EL" (EL34 etc.)

are the preamp tubes the el's or are they located inside the amp?

Your Triple's tubes should be 12AX7 x 5, 6L6GC x 6, and 5U4GB x 3. Is that what you have?

Your fuse blew because you have a bad tube. STOP playing the amp, your risking damaging other components.

It sounds like you have a bad power tube for sure, and possibly one or two pre-amp tubes as well.

Start with the powertubes. Call Mesa and get a replacement set. You can change the bad one and it's mate for now (they run in pairs like this, A-B-C-C-B-A), and get a couple of 12AX7's also. Even if the noise goes away with the new power tubes it's always good to have spares.

And get some fuses (more than one, the're cheap) of the exact same rating as what it says on the amp.

Dom

 

[yoursensesdrown]

dude thank you so much youve been such a huge help. im gonna order all that stuff from mesa tonight. i figured that was what the problem was. u shred man!!!!!

 

[domct203]

No Prob, I'm glad I could help.

Dom