When it comes to designs, say in cathode biased outputs, bypassing the power resistors
with good bypass capacitors does not alleviate the sonic effects that the power resistors
often cause.
I have found the Mills MRA resistors to be sonically exceptional. With that said, there is also an
MRB version. There is a physical difference.
1. The MRB incorporates a steel end cap where as
2. the MRA uses a "copper" end cap.
I have not compared the two for sonic differences, but that all are aware of the physical differences
normally cause sonic differences.
Hope this helps.
steve