Resistor types in Express

[ODwan]

Happy New Year to All!

One question: what are your experiences with different resistor types in the Express Style amp. Being an inherently rather noisy design I think the type of resistor used makes a great difference in noise performance.
I know from other builds that carbon-comps do sound somewhat sweeter than the average metal-film, but they are also very noisy. Any comments?

Greetings,
Timo

[martins3325]

Im not an expert on this but:
Ken used mostly Carbon Film resistors in his wrecks
Basically as I understand it there are 4 major types to consider
1) Carbon Comp - Supposedly warmest sounding but noisiest of the 3
2) Metal Film - Least noisy but it is said least warm
3) Carbon Film - What Ken used mostly and a nice medium
4) Tantalum - Very expensive, and i dont know much about em..but have heard they are great

[Robert]

One of the all time great sites for technical amp info, Aiken Amplification www.aikenamps.com, look in the Technical papers/Advanced section "Resistor types does it matter" and Geo Effects page www.geofex.com, search for carbon comp, about the 8th returned page deals with carbon comp resistors and where to use them. Try these papers, as well as the others, there is alot to learn. In short, I tried switching carbon film plate resistors with carbon comp resistors and can't say I could tell a difference. That is just part of the fun, experiment and find out what your ear reveals. Resistors are cheap anyway. Capacitor type seems to have a much greater impact on tone than resistors.