Tube Amp, Preamp upgrades -- what did you do that improved your units?

@grannyring With regards to Jeff selling what he carries- it’s just the opposite. He carries what customers want and expressed to me that even though he believes the KFPMs to sound better than the KPCUs, he has sold over 2,000 KPCUs and about 66 KFPMs. He keeps up with what there is demand for and is a stand up guy. I just wanted to address that point, the rest with regards to caps is opinion. All that matters is that you enjoy the music! Thank you for the kind words, and respect :-)

Agreed. My point is vs Jupiter caps and those are not being carried for other reasons beyond what we want as I understand it.


Jeff at Sonic Craft is a great guy and I have learned a great deal from him. Big plus for the industry! I will try the other Miflex caps based on your comments here. I have only tried the KPCUs based on Jeff’s suggestion.

Yes Solen Fast caps are made in France. They could very well be used by QS. They are the very definition of modest quality…at best. Dull and flat sounding compared to the better ones mentioned here. Used by many builders because they are very low cost. Some builders do have real cost constraints to contend with. 

I agree with granny again.  Miflex are really great caps but they are forward (not harsh though) in their presentation.  I've never heard an ODAM sound congested.  At the risk of sounding VCap biased, maybe the Odam was revealing something in the source component?  

I also love the British made ClarityCap.  I like them (personally) a touch more than Audyn's higher end stuff.  The good to best ClarityCaps can sound holographic and surreal while being pretty neutral.  

Auricaps are great on a budget. 

Mundorfs are overall great caps. I just like the other options for my taste. 

If you really want to experiment, you could buy the Musical Paradise preamp, which allows you to roll coupling caps as the unit uses binding posts (like speaker posts) for coupling caps!  Very cool.  I picked one up for $500 and use I to test out cap sounds.  I know, though, that the results are a skewed by the circuit too, yet this preamp has a fairly simple design. 

For clarity and to conclude my posting, my post is to offer alternative viewpoints in case the OP wanted to try something different. Considering the same issue is not there with other caps, I would rule out other variables. No intention of bumping elbows here.