Fuses that matter.

Rodman99999, Power supply is in the output stage to some degree. When power supply has no load regulation and amplifier has zero feedback then performance of the power supply (including inductance and ESR of big caps, resistance of the fuses etc.) plays part. Amp's negative feedback of 40dB would reduce this effect 100 times while regulated power supply would make it at least another 100 times better, and that's what is inside of my amp - at least 10,000 times reduction of power supply effects. As Al stated - don't look for any scientific explanation of the fuses. It is sort of "audio magic" thing. We don't even know if 3A Hi-Fi fuse is not really 3.5 or 4A standard fuse since AFAIK there is no test or approval of any agency. I wonder if datasheet, showing performance curves is available. I doubt that silver has lowest resistance times melting temperature factor since fuse companies developed special alloys (often lead&tin sometimes with cadmium and small amounts of bismuth and silver). I also don't know how gold plating improves things, since gold is relatively poor conductor. Another thing is directionality of resistance. Somebody suggested that direction that wire was drawn is causing it. I conducted test, a while ago, on spool of about 4000' of wire and resistance was identical, as far as I could measure with 6 digit Multimeter.

Has anyone here observed a clear difference in sound by reversing fuse directions back and forth immediately after initial installation?? It seems possible that after being conditioned by a load in one direction for a while and then reversing so the load is now going against the ‘conditioning’ or ‘break-in’ - the resulting effect sounds better to many. This matches my experience with the Supreme fuses since I didn’t hear any directional difference on day one, but did after reversing the preamp fuse a couple weeks later.

Kijanki,

I hope for the benefit of the custom fuse owners that the makers of these care as much about making sure the fuses serve their primary function properly as a prerequisite to whatever specific they might do to make them "sound better", but there is little or nothing to indicate they do. That alone disqualifies fancy fuses to me. I'll seek to invest my money in power tweaks elsewhere thanks.

I would not use a fuse marketed exclusively under the premise of better sound for this reason even if someone gave them to me for free and I actually thought they might sound better.

05-31-12: Kijanki
We don't even know if 3A Hi-Fi fuse is not really 3.5 or 4A standard fuse since AFAIK there is no test or approval of any agency.

Furutech fuses have the following approvals: PSE, CE, UL

Isoclean fuses have the following approvals: UL, PSE, SA, and CE

bc

Hi Al (Rodman),

I think that your points are generally well taken, and I realize that they are backed up by a great deal of relevant experience.

The one point I would make in response, though, is along the lines of Kijanki's comment. It is often said that the power supply and the power source are in the signal path, and that is certainly true in a sense. However, as I'm sure you realize but others may not, the effects of power anomalies on what ultimately goes into the speakers (or at least those effects that are explainable based on generally recognized science) will be greatly reduced by filtering and smoothing that is provided in the power supply, by filtering that is (or at least should be) provided at or near all circuit points where the outputs of the power supply are used, by the power supply rejection ratio of the circuit stages that directly process the signal, and in many components by voltage regulator devices and circuits.

I think that a good indicator of the significance of the distinction between being directly in the signal path, and being indirectly/in a sense/sort of in the signal path, is that if this thread were about fuses that are in speakers, or fuses that are in amplifiers in series with their outputs, I suspect that it would have ended about 300 posts ago, with little or no controversy. I, and I suspect most technically-oriented fuse skeptics, would consider it highly surprising if there were NOT significant sonic differences between fuses in those applications.

Best regards,
-- Al