People like wallowing in the bog of their own ignorance, it seems.

[cactuskeeb]

These folks should know - if one were to swap one cap with another that has a different value, in order to make any difference, sound-wise, in a circuit, the new cap's value would need to be +/- 50% of the value of the original cap; however, this difference cannot be heard by most of us unless the cap is swapped with something (at least) +/-100% of the original value.  In other words, looking below, we see caps that will, as a rule, not differ from each other in terms of our perception of how they sound when placed in the circuit design of a vintage marshall or hiwatt.

Moreover, in my experience, the .022-marked capacitors will measure .02; and the .015 rating is never the actual rating of the capacitor because in this uncommon territory (.01-.02) there is hardly any consistency between the manufacturer's listed spec (.015) and the actual spec (.017 is more likely what you pick up on these things [below] where you to measure them).  Anyway, 'food for thought' I guess.

[raisingfreen]

Cactus, thanks so much for this information.
Can you explain this advice (below) I received about reducing the mids and bass of my tweed deluxe? The amp is extremely dark sounding with humbuckers and I would love to have it be a bit less bass and mid heavy if in fact it was as simple as a few cap swaps.

---"You could try changing the 2nd stage cathode capacitor from a 25uF (stock value) to a 0.68uF (less bass, brighter overall tone).
Also, you can swap the value of the coupling cap on the bright channel from 0.1uF to 0.022uF to brighten it up a bit".----

This seems to be the standard advice for owners of a tweed deluxe who feel its too dark with humbuckers. It does sound great if I scoop the mids with an EQ however.

Thanks

[cactuskeeb]

That would do the opposite of what you want.  And you'd only do that mod (it's the marshall-ized mod -- you do it to the normal channel) with a deluxe reverb. 

It doesn't even make sense with a tweed deluxe...where's the bright channel on those things?  I'm a little confused.  I'd like to help more and talk about it, though.

Sorry it took me so long to respond, i missed this post -- send me a message next time.