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Fuses fuses fuses

Ok, this is about fuses

1- a standard Bussman fuse is UL approved. Are any "high end" fuses UL approved?

2- do any component manufacturers supply their gear with any of the usual suspects of high end fuses as opposed to a standard Bussman?

3- let's say fuses do make a difference. Given incoming power is AC, why could fuses be directional? 

Not meaning to light any fires here- 

thanks in advance 
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geoffkait's avatar
geoffkait
14,147 posts
 
Lee J. Cobb who played Juror #10 (the last holdout) was also great of course in On the Waterfront as mob boss Johnny Friendly. Also as Willy Loman in Death of a Salesman.

georgehifi's avatar
georgehifi
4,966 posts
 
Of course engineers have measured fuses.

Not in the way you promote them, they wouldn't be stupid enough.

Cheers George
geoffkait's avatar
geoffkait
14,147 posts
 

georgehifi
Of course engineers have measured fuses.

Not in the way you promote them, they wouldn’t be stupid enough.

Cheers George

>>>>>If you’re pretending to be dense you’re doing an excellent job. ( Juror #2 from 12 Angry Men)

Who do you think measured the directionality of fuses that are shown in the HiFi Tuning data sheets? Engineers. And they measured fuses in EXACTLY the way I promote them. I.e., conductivity is better in one direction than the other. Duh! 
geoffkait's avatar
geoffkait
14,147 posts
 
Time for a fuse measurements recap. Interpretation of measurements. All aboard!

INTERPRETATION OF MEASUREMENTS (HiFi Tuning data sheets)

(verbatim)

There is a measurable difference in directivity of fuses. Mostly that will be due to the way the melting wire is manufactured. The difference is in the range of 5 % . That is in the range of variations due to the factoring process, but the difference is measurable with all types of fuses.

The resistance of the fuse itself is dependent on the length and thickness of the melting wire. At pure DC- resistance measurements, of the commercial available fuses, the solder type with leads gives the best results. Worst results gives the fuse with a glass tube and spiral shaped melting wire.

The high end fuses all give better results in conductivity, the cryogenically treated fuses from HiFi-Tuning give the best results, while the rhodium coated fuse from Padis gives the highest DC- resistance.

For DC applications it ́s recommended to use the solder type fuse or the cryogenically treated fuses from HiFi-Tuning Germany.

The drop in resistance up to the factor of 8 is clearly measurable and also could be detected in listening test.

Fuses with a glass tube and a spiral shaped melting wire are additionally by a factor of 20 more sensitive to micro phonic effects. Fuses with a glass tube and a straight wire still by a factor of 5.



bdp24's avatar
bdp24
4,908 posts
 

Modjeski tested the resistance of the Hi-Fi tuning fuses in both directions, and found a difference of 0.038 milliohms. I don't know about 5%, but 0.038 milliohms is an EXTREMELY small difference. I have no doubt that fuse directionality proponents will say the difference in sound is due to other factors. Like what? Oh yeah, wire directionality ;-).

Roger called and talked to both the Hi-Fi Tuning fuse U.S. distributor, and the fuses German designer. Neither knew what the term "high breaking capacity" means. Roger strongly advises against putting a Hi-Fi Tuning Fuse in a DC circuit (tubes run on DC), as a fuse lacking hbc will not protect an amp---by blowing, when a tube goes bad---as they all eventually do. Even a new tube with a short will blow a fuse capable of performing that function, which the HFTF in a DC circuit is not.

Roger Modjeski characterized  the Hi-Fi Tuning Fuse as "junk". But then he's delusional ;-).

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