Top resistors

Johnss: Which Vishay bulk foil are you referring to?

The Vishay S102C (non nude version) I tried in the signal path in a direct coupled position between amplification stages. This resistor is highly colored in that it strips music of harmonics resulting in a tonally inaccurate sound. The Vishay (TC) TX2575 is much more tonally accurate , harmonics are presented intact. The sound of a maraca sounds like a percussion instrument through a TX2575. Through a S102 (non nude) it sounds like gravel inside a soda can.

Try painting the nudes with AVM its part of my Blue Period.
Tom

Vishay VSRs.

Similar to the S104.
the biggest improvement are the shunt resistors (47K, 100K etc) where they are loading the output of one of the stages.

http://www.datasheetcatalog.org/datasheet/vishay/vsr.pdf

Also keep in mind they will let through what ever is in the signal path, so if you are using in SS gear, you likely will need to add bypass caps to the power supply if not already there.

I haven't done any experimentation myself, but, I know people, including small manufacturers of ultra high quality components, who say there is no such thing as a best or top resistor, capacitor, or any such component. I asked one why he worried about a certain "cheap" resistor becoming unavailable, and he said that he had tried many others, such as Vishay 102Cs, and for his circuit, in his opinion, they sounded dry and analytical. I heard the same from another small manufacturer.

It would be much easier if there were such a thing as a clear upgrade path, but, that is not the case. I heard an "upgraded" version of an amp I am familiar with that sounded shockingly bad compared to the original. It turned out that the upgrade consisted of just parts substitutions of Black Gate caps for the cheaper caps the manufacturer used. In this particular application, the Black Gates were NOT appropriate.

I built my Hagerman step up using basic bulk Vishays. There are only 2 resistor locations directly in the signal path. With the basic Vishays the sound was good, but not as transparent as I had hoped. I tried the (very expensive) nude Vishays in those 2 locations and things opened up dramatically. Maybe too much.

I then put a Riken Ohm into the second location, leaving the nude Vishay in the first, and it warmed things up nicely without losing that transparency.

As it turned out my cartridge loads as 220 ohms, which was the value of that second nude Vishay that I replaced with the Riken. So I replaced that loading resistor with the nude Vishay and got another leap in transparency, even though it was not directly in the signal chain.

So I have found that resistors do in fact play a role to tune the sound in a sensitive circuit. I have also found that those white paddle Caddocks are very nice, though also very expensive. Used judiciously for tuning these can be a great improvement, but they are far too expensive to use everywhere.