need advice, mark III service

[axwielding1]

My mark is a 1988. I've been noticing a kinda ghost note very low, but noticeable. Sounds very high gain. I hear it when playing clean...
Does this mean I need a cap job?? I'm thinking of sending it to Mesa for a complete "go through".. How long should it take, and approximately how much is a cap job?
I would also have a complete re-tube. I think the EL34's are getting dull, as I use them in class A alot, and loud.
Also, my effects loop doesn't seem to work, or at least not very well. I put my DD6 through it and got almost nothing.
Any ideas on prices?
I know I gotta call Mike B. and get the full skinny, but I'm just curious.
Also, any other suggestions while it's out there????
ax. :twisted:

 

[Boogiebabies]

Could be time for a cap job, loop jack and tubes. The ghost note may be the pre or power tubes or caps. The loop may have a bad return tube and may not be passing the signal and may be the ghost note culprit as well. I had a ghost note problem when I fist started using the GT 12AX7M's. The first three I used gave me snaps, crackles, pops and octave harmonics. It drove me batty until I put a good one in and the problem went away. Yes, three bad ones in a row. The high gain may be an LDR not closing all the way as well and bleeding the lead channel. You can even remove it from the cabinet and visually look for signs. You dont even need to touch anything.
Look for burnt resistors, cold dry gray looking solder joints, loose caps etc. Try the simple stuff before you waste your money shipping it across the country.

 

[axwielding1]

Thanks boogiebabies. I will re-tube for christmas..When out of the cab, I'll give it a look through.. Last time I had it out, I didn't notice any problems, but I'm not exactly trained to see 'em either...
Maybe I'll take a few shots and see what you may be able to see from the pics... It's really quiet, no hum or anything. Just that ghost note deal..
BTW, I took out the GT pre's and installed the SPAX7's, and mesa ECC83's that were in there previously. Maybe I'll try the GT's again. I really liked them.
Thanks man....
ax. :twisted:

 

[Boogiebabies]

The GT's, when working properly are very good. I tried NOS RFT's the other day and it blew them away. More gain, smoother and more natural bottom end. I would be happy to look for any spots. Russ B. has a good eye as well and I am sure he will help. A trip to Mesa can get very expensive.

If you are doing a retube, check out www.dougstubes.com. He is out on the Island and is a serious tube afficianado with a Hickok, Maxi matcher and the VTV preamp tube tester. He also is very reasonably priced and close to you.
He has GT, Ruby, EH, Mullard and NOS.

BTW,

Does it ghost out through a different cabinet. I had a Marshall cab that was way too sympathetic to a clean low E and would shake the walls whenever it saw that low E.

 

[axwielding1]

My son has a 4-12 with 85 watt celestions. I'll try that today...
I'll check out Dougs tubestore as well.
ax. :twisted:

Thanks 8)

 

[Boogiebabies]

No problem.


Good luck.

 

[RussB]

Ghost notes are weird things, and can be caused bu many things.

I had a '67 Vibrolux here once that had a funky JJ power tube that had a "ghost" in it! Took me many hours to track that one!

Sometimes it can be a parasitic oscillation in the circuit. These are a "mutha" to track, especially in a complex circuit like a MKIII.


Ditto on Doug's Tubes. He's my "go to" guy for all my tube purchases

Double-ditto on the GT-M's. I bought 5. All 5 were returned for replacement. 3 replacements have crapped out! The other 2 have't been used yet! Jeez!

 

[axwielding1]

Moved and switched out pre-amp tubes and problems are solved...
The effects loop is now fully functioning and clear sounding. No ghost note..I think that note was from the E-loop tube.
Now I'm crystal clean, clear...
Thanks guys...
ax. :twisted: