#1
My 6505+ head has a rediculous humming at all times, the clean channel is super quiet, and the tubes don't glow too bright...is it time to replace the tubes?
**GEAR**

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#2
tubes do not always glow too bright

try your amp on a different outlet/building power

try swapping the V1 preamp tube with the V2 preamp tube.

try a brand new preamp tube in several places.

do the pencil test on the preamp tubes.

use your warranty?
#3
You should always have a spare preamp tube. Go buy a JJ 12AX7 (get the ECC83S version and get a balanced one if you can). Always have one. In such situations, you just try it in each position until you fix the problem - then go out and buy another spare.
The reason you buy a balanced one is because the PI is usually the first to go and it should be balanced. So off to the shop. That's a JJ 12AX7S. The short plate Telefunken copies. The other JJ is long plate - not good for you. You want the ECC83S.

Edit: Actually, no. Wait. You have the head not the combo. The long plate one is the one you want. That's the ECC803. That's the low noise old Tesla version. Ever slightly less gain but will help tame some of the 6505 noise.

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Last edited by Cathbard at Aug 3, 2011,
#4
Well 1 of the power tubes is brigter than the other 3...is that a problem?
**GEAR**

Epiphone G-400 Tony Iommi Left Handed
Custom Epiphone Les Paul 100 Left Handed w/ EMG 81/85
Johnson Acoustic Left Handed
Line 6 Spider Valve 112 w/ FBV Pedal
BOSS DS-1 and AC-3