PADIS vs Furutech fuses

Well, I hate to step into the middle of an argument (which unfortunately is becoming far too common here) but the topic posted from the OP is relevant to me at this point in time. I have been considering fuse options for my gear. I am still sitting on the fence, so to speak, as to the validity of fuses making an audible sonic difference, but being as how it is a relatively low cost venture, why not give it a go? In my own instance I have a six figure system, and the outlay of a few hundred dollars to try a few fuses is miniscule in comparison, and may indeed provide an improvement. If it does not, so what? I'm not out a lot of $$

For those that do not agree with the fuse upgrade concept, please refrain from trying to dissuade me.

I have a few questions for the "fuse" community. My virtual system is listed so I won't bother being redundant (and I hate typing) I do not intend to replace through all the components at this point in time. As I said, I'm just testing the water to see if I can hear a difference. Any advise on what components that I should swap out first, and any recommended fuses for them? I am also wondering if there is an easy/safe way to "burn in" prior to installation. Please keep in mind that all of my gear is left powered up 24/7, with the exception of my pre-amp, and phono stage, which are both tube units. I'm not comfortable leaving tube gear running 24/7

Well, one piece of information is that your Bryston 28B amps do not use fuses. They use circuit breakers instead. So you don’t have to worry about those pieces.

As far as testing the waters, I would probably start with your ARC LS 27. It looks like it uses a 3A fuse and it appears (based on the pics) that it uses the large 6.3mm x 32mm size fuse. You don’t have to burn in the fuse on the ARC. You can use an alternate device, such as maybe your MAC CD player? (as long as the physical size is the same). A 3A fuse is somewhat larger that I would put in a solid-state source device, but you could run it in for 10 days before placing it in the ARC. If you liked the results, you can try in your RIAA phono stage and your CD Player or MEN220. For fuse burn-in, you do not have to play audio through the device. You just have to make sure the device is powered on.

For fuse selection, we all have our preferences. I personally do not like silver based fuses (Hi-Fi Tuning, Synergistic SR20) because they have a push in the upper mids and sound artificial to me. They very fast and detailed, though. I think the silver does not have the ultra-high frequency “air” that the Furutech fuses have (I think silver actually rolls off the very high frequencies somewhat, we are talking like above 14khz or so). I have read that ARC is very high resolution and resolving for tube gear, so Hi-Fi Tuning or SR20 may not necessarily be the right choice. It highly depends on personal preference. There are some who like Hi-Fi Tuning better than Furutech.

There was one user who put a Furutech in his tube amp and had improved sonics. When he replaced the Furutech with a BLUE fuse, he did not hear any difference. This could be limited resolution from the tube amp. Others that have upgraded from Furutech to BLUE indicate a good improvement in sonic quality. Others indicate that BLUE may tend to roll-off high frequencies in comparison to BLACK. However, this could also be that BLACK fuses are very sharp in the high frequency detail. I have not tested BLUE or BLACK personally, so I could not be sure. The BLUE/BLACK are definitely a lot more expensive than Furutech, but they have a 30-day return guarantee..

One thought I had was to ask how attached you are to the MEN220. A quote from the following link:

https://www.audioaficionado.org/showthread.php?t=5072&highlight=MEN220+Review&page=31

I thought it might be of interest to some. I scrutinized the service manual for the men220. The analog inputs are digitized by a single akm ak5394a analog to digital converter(adc). This is a 24bit/192khz delta sigma adc, sn/dr of about 123db. There is a separate adc for the microphone input(akm as well). Then the signal is processed (room correct) in 2 Texas Instruments audio dsp, there is also an altera fpga in there. As a final step, the signal is converted back to analog via 2 wolfson/cirrus logic dacs, one per channel. These are 24bit 192khz dacs with about 120db sn/dr ratio in differential mono mode.

Since it is a digital signal processor (DSP), it is required to convert the analog signal to digital before doing the equalization/crossover. Then it converts back to analog via a DAC chip. You will lose some of the original analogue sonic signature doing this. Have you ever thought about removing the MEN220 from the signal chain and see how it sounds? If you have an environment which absolutely requires room correction, maybe this isn’t a good idea. Just a thought.

I did some calculations of the resistance of various light bulbs based on their wattage ratings, which reflects their "steady state" resistance following the brief warmup that occurs at turn-on. I also measured their resistances with a good multimeter, which reflects the "cold" resistance they would very briefly have just after turn-on. The bottom line in each case was well over a 10:1 difference between those two resistances.

Which makes using a light bulb a tricky matter at best. Depending on the fuse rating and the wattage of the light bulb you would probably have either too little "steady state" current to be effective in a reasonable amount of time, or too much current during the instants following turn-on, which might blow the fuse.

I also thought about the possibility of using a resistor instead of a light bulb, since a suitably chosen resistor would provide essentially the same resistance immediately following turn-on as it would subsequently. However the problem with that approach, assuming you would be powering the setup with 120 volts AC, is that the power handling capability of the resistor would have to be very large.

So what I would suggest is that you use a Variac in conjunction with the light bulb approach. I suspect that you can find a used or possibly a new Variac inexpensively at eBay. That would allow you to bring up the AC voltage applied to the light bulb/fuse combination slowly, to avoid excessive current flow while the bulb is heating up.

The resistance of the fuse itself would be negligible compared to the resistance of the bulb. The resistance of the bulb can be calculated from its wattage rating (its actual wattage rating, not the "incandescent equivalent" rating) based on the following relation:

R (in ohms) = (120 volts squared) / (wattage rating)

So for example a 53 watt halogen bulb having a 75 watt incandescent equivalent rating would have a steady state resistance of:

R = (120 x 120)/53 = 272 ohms.

The resulting current would be:

I = E/R = 120/272 = 0.44 amps

For a bulb consuming 100 watts:

R = 144 ohms
I = 0.83 amps

For a 250 watt bulb:

R = 58 ohms
I = 2.1 amps

The burn-in current should be limited to no more than around 1/3 or at most 1/2 of the current rating of the fuse.

Variacs intended for 120 volt applications can generally be turned up to put out voltages that are somewhat higher than that, so you would probably want to use a multimeter to determine the setting corresponding to 120 volts.

... Regarding flicker bulbs, a point to keep in mind is that the only audio components whose AC power draw fluctuates significantly are power amplifiers that are not biased in class A. Or subwoofers or speakers which incorporate such amplifiers. Class A amplifiers, preamps, other line-level components, phono stages, etc., all draw essentially the same amount of AC current at all times.