Ok I was going to save the King/Cello tape preamp for the Audio Review section. But I'll give a few impressions here since I'm the only one so far that had the opportunity to directly compare the "stock" version with the new Au/Ag "Mundorf" oil capacitor equipped version (both in SE form) in my own system thanks to the generosity of Charlie King! For the record, the Mudorfs will add about $320 or so (4 x 1 uF @$80 or so if on sale at partsconexxion.com) bring the cost of K/C tape pre to around $4170 . That said, one also get for the money a high quality phono section with 40, 50 and 60 db of gain; Charlie has been pushing me to listen to the K/C as phono but haven't had the chance yet.
I'm not sure how many have ever seen clinical trials closed way before the target date because the results were so statistically significant that it didn't make any sense to continue it.
That was what the Mundorfs were in comparison to the stock caps. Now I'm not one prone to hyperbole and unbridled enthusiasm but I have to say the Mundorf totally wiped out the stock caps (and the caps had about 150 hrs of playing on them-so they were well on their way to being burned in). Bass extension, lower noise floor, cymbal weight, midrange presence and harmonic content, imaging: all were siginificantly better with the Mundorfs (now how would it have sounded with Duelands? I sure would like to know but there cost was a little prohibitive to try for an experiment). Three 15 ips/2 track tapes, Roy Haynes Out on the Afternoon, Bill Evans Waltz for Debby and Hindemith VC, were all it took to hear the differences between the two units (done with the same ICs, power cords and left powered on for the whole comparison). Much of that murkiness I has associated with the TP project tapes in my system was reduced. One example of the increased transparency was the Jacqui Naylor recording, one that naysayers said was the weakest of the first TP lot; thru the K/C, she sounded like totally different singer and closer to what I heard when she performed at the Blue Note in NYC this winter. Her voice was lighter-yet it had a body that I don't normally associate with female vocalists.
That said, I wasn't getting the lowest octave and midrange harmonic content that I had previously heard with the K/C in my system (I had the opportunity to hear the K/C on several occasions before purchasing). Yes the Mundorf caps were better, but there was something missing with the newest modded unit. I tried many things including isolation of the power supply, different IC cables, etc. but the bass say on the Arnold Overtures wasn't as room rattling as before.
Then it dawned on me, and this is an interesting finding on long term memory of familiar items in one's system, that one of the two ESP Reference AC cords that I was using in the comparison, hadn't been treated with the audiodharma cable cooker. In fact, this was the section used as a control in the audiodharma review for Positive Feedback. And this the cooked ESP AC cord was being used with the stock K/C; so I hooked the cooked AC cord up to the Mundorf version and voila, the bass was back and pianos for instance were better fleshed out.
So that's a little sneak preview.