You might've noticed I'm using the Dry Pass on the Finally in that picture...
In reference to the note in that previous post, I spent most of the evening last night auditioning different tubes in my Finally, trying to find one that I felt sounded best with bass, guitar, and guitar distortion. It was a fun excuse to play for a few hours, and I wanted to share my observations in case they end up helping someone else.
The Finally is being used last in the chain as a tube-flavored "sweetener", here are my anecdotal observations with different tube types:
12AU7 - In pursuit of maximum clan "headroom" this is what I started with, and true to form the Finally with a 12AU7 could only be pushed into saturation with Gain cranked and a clean boost slamming its input. It sounded good on bass with accurate reproduction and just enough tube "roundness" to be present. However, with a distorted guitar in front of it, the 12AU7 was
really rounding off the jagged sizzle of distortion pedals; I did find the rounding effect could be somewhat reduced by turning the Gain way up and the Level down on the Finally.
12AV7 - It had more output than the AU, so Level had to be turned down a bit; and it could
just be pushed into saturation if the Gain was maxed and an unboosted bass or guitar was played into it
hard. On bass it was virtually transparent sounding, very accurate sound reproduction, adding only the slightest bit of tube roundness. With distorted guitar it was still rounding off the sizzle, though probably only half as much as the AU did; again the distortion-rounding effect could be somewhat reduced by turning the Gain way up and the Level down on the Finally.
12AY7 - Generally I feel AYs are a better choice than AVs when used in the same bass/guitar amp circuits. In this instance it sounded and responded virtually identical to AV in every way, except that it had a lower noise-floor (almost dead silent even at max Gain), but since noise varies from tube to tube and isn't usually a feature of a specific tube
type, I'd chalk it up to random luck.
5751 - More output than the AV and AY, so again Level had to be turned down a bit. I only own one 5751 and unfortunately it's one of those supposed "holy grail" tubes (RCA black plate). I wish I had a GE or Sylvania to compare to because as much as I hate to admit it, this old RCA 5751 really
does just sound excellent in everything I put it in; but I don't know if it's because it's an old RCA, or if all 5751 are really good, or if this one tube just happens to be a good one... Anyways, sound reproduction is excellent with a slight extra
something that's hard to explain (and wouldn't be audible as soon as one other instrument is in the mix), saturation begins with Gain at 2:00, bass sounds great, distorted guitar retains its character and sounds great. If you're gonna use your Finally with both bass and guitar, give a 5751 a try.
Pic of the Finally with the 5751 included for reading such a long and silly post: