Top resistors
I’m sure everyone would agree that assessing sonic characteristics of parts in a complex audio system is extremely challenging due to component interactions, but here’s my experience. Shinkohs and Riken Ohms are nice, but just too colored, in a nice way, to use more than just a few. Have tried the old Holcos, but despite added clarity, they were a little thin sounding in the system I had back then. The Dales are natural sounding as are the old Resistas, but neither of these are as transparent as the naked Vishays. I think the resistor of choice is the TX2575. There may be some ultimate limits even on these. After swapping in almost 80 of these in the signal path of my 2 hybrid tube amps, 60 in the crossovers, and 70 in the phono stage, I had to put 2 Resistas back in to restore a little more midbass/lower mid-range warmth (the Dales would have worked equally well). That’s all it took. Sadly, I did lose just a touch of transparency. There are always some tradeoffs. Everyone has there own preferences. It’s really amazing (maddening?) how much changing only a couple of parts can dramatically change the sound of a decent audio system. I’m hoping to be done with all this soon! |
@pbnaudio Fusible and flame-proof resistors are quite common in the electronics industry but usually in an amplifier, not a crossover. :) The idea of the former is just like you would expect. When power is exceeded they are guaranteed to open, instead of potentially shorting or catching on fire, and save the rest of the device from a complete meltdown. Duelund's are really weird. One of their selling points is that they have a high sensitivity to heat and power so will change values rapidly. The very last thing I want in a power resistor! :) For speakers I stick with Mills. VERY thermally stable, very quite, very tight specs, and really small for the wattages. Also reasonably priced, all things considered. I do want to someday work for a speaker company that will let me build with some caddock resistors and heat sink them, but so far I haven't the time / energy / funds to experiment with them. |
@erik_squires I think you must be referring to this type of fuse http://www.mouser.com/ProductDetail/Littelfuse/0251002MXL/?qs=sGAEpiMZZMsNIlwy3aAdUVxIQvxhy%252bighe... which is a fuse not a resistor, although to a layman it might look like it. That being said I find your posts enlightened and offering good advise. I believe that this thread was questioning why one speaker manufacturer use resistors as fuses, which I consider sub par engineering at best and further evident as some report that these change value over time - which of course they will as they heat up - cool down. Depending on their insertion in a crossover I use different resistor types, if in a zobel network for impedance correction of a woofer or midrange generally I use 25W cement resistors and almost always several in parallel as to get the power handling up where it needs to be. For attenuation of a tweeter, which I generally try to avoid, I’d use either the Caddock MP9100 which I heatsink or several 5W MOX resistors in parallel again to get the power handling up. I agree Mills non inductance resistors are nice too and use them on occasion too. http://pbnaudio.com/speakers/speaker-kits/scanspeak-b741 Above is a link to a kit I designed for ScanSpeak a few years back - this will give a good indication on how I propose the use of resistors in a X/O network. Good Listening Peter |
