Preamp Output Capacitor: Mundorf Supreme vs. Supreme Silver Oil

You're right!  That should teach me to do math in my head.  I dropped a digit.  

Of course that makes the issue of the value of the cap even less significant sonically.  With tube gear where the input impedance is typically 100K or more, a 0.68uf coupling cap is fine.  

My experience matches that of  @salectric 

With tube gear where the input impedance is typically 100K or more, a 0.68uf coupling cap is fine.

The smaller value you can get away with, the better the cap itself will sound (and no need for a bypass). That is why we have a direct-coupled output in our preamps, so that the significant cap in the circuit is only 0.1uf.

Could someone explain why adding a 0.01uF capacitor in parallel/bypass with a 2.2uF capacitor improves sound quality? 
If this is way off topic and I’ll delete the post and ask elsewhere.
Thanks.

Not everyone agrees that a small bypass cap improves sound quality.  I have tried bypass caps in all sorts of applications going back literally 40 years and I haven’t found a single instance where the bypass improved sound quality.  The bypass certainly changes the sound; usually the bypass makes the sound brighter, leaner and less coherent.  I much prefer the sound of a single quality cap like a Copper V-Cap over any combination of caps with a bypass.

You may reach a different conclusion so by all means try it yourself, but don’t be surprised if you tire of the sound with bypass caps.