Jexrexpro,
I have experiented a little on bypassing, the 1% or 10% rule of thumb did not apply when using exotic caps as bypass.
A 0.001% and 0.0001% made very noticeable changes which follows the sonic characteristic of the high quality bypass cap. When i mean exotic, they are duelund cast, vcap tftf, vcap cutf, mundorf silver oils and silver golds.
The bypass values were 1uf for duelund cast copper, vcap tftf.
0.1uf for mundorf silver oil and silver gold oil. 0.22uf for vcap cutf. 0.01 for vcap tftf and noe duelund pure silver foil.
For what i found, even a 0.01uf on a 10,000uf cap gave a very strong sonic character of these exotic caps which i have used in the signal path of my preamp prior to using them in the power supply as i have gone passive and had all these caps sitting around. I would never have spent such money for osu bypassing using these caps, maybe a 0.01uf as cost can go to a fair bit.
Interestingly, these exotic caps which have a very strong flavour on it's own exhibited the same characteristics in the psu section as a bypass.
There are caps which i have used a main signal and bypassing which never stayed in place for more than a few song selections such as auricap, hovland, mundorf supremes, siderealcap, almost all of the multicap range with the exception of the RTX.
I would say a 0.1uf would be enough to gain a large amount of the bypasscap sonics for a 22uf main cap presuming that is the cap in the circuit that is critical which youbwould have found by swapping of lower quality caps.
It is most important to know what you want from the sound and have a good idea of the reference quality and characterics of good sound as opposed to just ore sparkling highs , warmer and more natural mids and the favourite, better bass as one can easily get carried away.
The duelund copper cast for example at 1uf bypassimg a 10k uf reseviour in digital gave in 2 different systems a superb analogue sound reminiscent for vinyl playback.
It was exceeding beautiful, pleasing and enjoyable. If i had not swapped in a vcap tftf lying around o the same value, i would never have know what i was missing.
The vcap alone did not work as vocal became bone bare and lacked a the presence of the duelind or a mundorf silver oil. Bass, depth, highs and blackness was to die for with the vcap bypass and would fair better playing new age or some instrumental music.
The choice of bypass would be best selected having a strong reference of what you want and how your system sound currently.
Each a every different system will have a different selection. However, over the years tweaking my system and also a friends system, i found that when the improvement made by equipment, room acoustics etc and it gets to a point where the selection of these finishing touches are large and become almost identicle, meaning that the sonic traits such as bypassing with impact 2 different systems very similarly.
Different systems meaning a back a few years ago, 1 system was warm with full bass and the other clean, tight, leaner and tilter towards the shrill side. What worked for 1 didnt work for the other, now 2 systems have converged to react very similarly to tweaks such as cap bypassing.
My presonal recommendation would be to bypass using a 0.1uf to 0.47uf cap, duelund cast cu, vcap tftf and cuft, mundorf silver, gold and oil series. These have probably have very strong traits but not over extreme and still rather balanced sounding.
Interestingly, the Jupiter copper foil is a very balanced and fine sound cap when using on its own in the signal path. Being extrement well rounded in all sonic parameters dont seem to impart much as a bypass.
The new duelund 0.01uf falls also in that category, adding clarity,,mtexture as a bypass, but does excel in any one area as a bypasscap.
