Do old signal caps sound like "Fudge" or sticky in preamp ?

[petemoore]

  I have this cool old RTR amp I've put an IEC into, stripped a buncha stuff outta.
  Works !
  Sounds fine up to a point, then sounds blatty, wondering if the caps would do that.
  Otherwise no noise floor on this one.
  I know this should be at ampage, but since I found the negative end of my xicon polarized capacitor the thread would have been a waste.

[Ripthorn]

Is this an axial capacitor?  If so, the little indentation around the can marks negative.

[petemoore]

  Black side seems logical, the Mouser tech said he'd bet on it being the black side.
  I hooked up the black side, no smoke, bumped gain up...
  So that cathode bypass capacitor is in there..
  The thing I'm trying to do now is figure out why the second of two 12ax7 preamp stages has a plate voltage of 80v when the other plate is at ~250.
  210k plate resistor and 1k5 cathode resistor, everything else being equal, I tend to suspect maybe a capacitor is leaking, pulling down the plate voltage.
  It gets nice and loud for a 6v6, but has the 'needs pushed through' type sound, some kind of gating it seems, V1a's plate looks funny voltage.

[alanlan]

Check all the carbon comps.

I'm currently renovating an original 1964 Vox AC30.  All the R's are up in value and a few (including a plate resistor or two) have gone hi-Z (not open cct but 5X what they should be).

[petemoore]

  I started with the IEC and getting the traces of reel to reel out last night, nice solid ground bolt.
  Had to do some stuff to get the amp working...blazed on very loud and rough...no volume control !
  Added VC this morning and the really cleaned it up nice [some new caps, BF preamp TC's and volume, tamed it down and AC bypassed a cathode etc. etc.
  This is one super charmer !
  It's really good sounding, 5y3, 12ax7 and 6v6 works great, smooth sound to bright...beautiful !
  Lightweight aluminum chassis bolts right back into the retro RTR cabinet/case, lid is removable, hinges and clasp in A1 shape, cleaned up really nice !