With experiments with volume controls go back as far as the 1970's, this is what has bought about the ldr Lightspeed Attenuator.
Almost all rotary switches have a stiff disc wiper made out of a different material to the springier metal that the leaf/leaves are made out of.The two contact points in relays are at least made out of the same material.
It is comon knowledge that two different metals that are a touch contact with current/voltage passing through them will creat a "diode effect" electrolosis or glavaic.
Herve Delartz of DartZeel backs this up as well, this is why he does not use contact volume controls either in his $25k NHB-18NS preamp but uses ldr's which have no contact.
http://www.6moons.com/audioreviews/dartzeel2/preamp.html
Quote interview with Herve:
Q: What is wrong with conventional volume controls?
A: You lose something. I use a system that varies resistance with light. However, until all the patents are in place, I would prefer not to specify the details.
Cheers George
Almost all rotary switches have a stiff disc wiper made out of a different material to the springier metal that the leaf/leaves are made out of.The two contact points in relays are at least made out of the same material.
It is comon knowledge that two different metals that are a touch contact with current/voltage passing through them will creat a "diode effect" electrolosis or glavaic.
Herve Delartz of DartZeel backs this up as well, this is why he does not use contact volume controls either in his $25k NHB-18NS preamp but uses ldr's which have no contact.
http://www.6moons.com/audioreviews/dartzeel2/preamp.html
Quote interview with Herve:
Q: What is wrong with conventional volume controls?
A: You lose something. I use a system that varies resistance with light. However, until all the patents are in place, I would prefer not to specify the details.
Cheers George