30-11-2016, 11:47 AM
(This post was last modified: 30-11-2016, 11:49 AM by Valvebloke.)
Superconductors for use in hi-fi are still in the realm of speculation AFAIK (although people are speculating about it). In areas with enough money, and hi-fi can be one of these, technology does penetrate though. The use of graphene in loudspeaker cones/diaphragms has been a hot topic for a little while.
Getting back to(wards) the original topic, Mark's wirewound resistors have an L/R current risetime of 0.73us, so a 10%-90% risetime of a little under a couple of microseconds. This is insignificant for audio signals, but not by a huge amount given the ludicrously small imperfections that some hi-fi folks worry about. It is actually within an order of magnitude of being an issue. If the current risetime was 20us rather than 2us then that would significantly round the leading edge of a 10kHz square wave.
Of course while having a perfect resistor might be useful for checking the performance of an amp into a well-defined load, it will matter relatively little when it comes to actual use in service. Practical loudspeakers are a very, very long way from being perfect resistors.
VB
Getting back to(wards) the original topic, Mark's wirewound resistors have an L/R current risetime of 0.73us, so a 10%-90% risetime of a little under a couple of microseconds. This is insignificant for audio signals, but not by a huge amount given the ludicrously small imperfections that some hi-fi folks worry about. It is actually within an order of magnitude of being an issue. If the current risetime was 20us rather than 2us then that would significantly round the leading edge of a 10kHz square wave.
Of course while having a perfect resistor might be useful for checking the performance of an amp into a well-defined load, it will matter relatively little when it comes to actual use in service. Practical loudspeakers are a very, very long way from being perfect resistors.
VB
Ampregen Ltd http://www.ampregen.com
