Fuses do affect sound, the question is how much

[Cbdb2]

Yes fuses affect sound. Blown fuse, no sound. Thats about it. One of the first few posts stated N Pass measured the distortion a fuse adds to a speaker at .0033% worst case, probably at high power. In a power supply 0%, ( I dont need to measure I know how a power supply works) your service AC variation will swamp anything your fuse might do. Never ceases to amaze me what people will waste there time and money on when theres elephants in/is the ROOM.

 

[Alice of Old Vincennes]

Although, to the best of my knowledge, this was never covered by

Duke,
View attachment 60840

The Duke, (*)
View attachment 60845

or the Thin White Duke.

View attachment 60844
_________________
* Note the sly deployment of the Oxford comma, just to stay on topic.

I am going to send my next monthly

Although, to the best of my knowledge, this was never covered by

Duke,
View attachment 60840

The Duke, (*)
View attachment 60845

or the Thin White Duke.

View attachment 60844
_________________
* Note the sly deployment of the Oxford comma, just to stay on topic.

Although, to the best of my knowledge, this was never covered by

Duke,
View attachment 60840

The Duke, (*)
View attachment 60845

or the Thin White Duke.

View attachment 60844
_________________
* Note the sly deployment of the Oxford comma, just to stay on topic.

Although, to the best of my knowledge, this was never covered by

Duke,
View attachment 60840

The Duke, (*)
View attachment 60845

or the Thin White Duke.

View attachment 60844
_________________
* Note the sly deployment of the Oxford comma, just to stay on topic.

I am going to send my next payment divisible by three to your suggestions. I may need a generator if Duke disconnects.

 

[A800]

Yes fuses affect sound. Blown fuse, no sound. Thats about it. One of the first few posts stated N Pass measured the distortion a fuse adds to a speaker at .0033% worst case, probably at high power. In a power supply 0%, ( I dont need to measure I know how a power supply works) your service AC variation will swamp anything your fuse might do. Never ceases to amaze me what people will waste there time and money on when theres elephants in/is the ROOM.

Overpriced fuses will affect the sound even more.
Less money for better speakers.

 

[Blumlein 88]

The Duke, (*)
View attachment 60845

Even on a Honda he rides tall in the saddle.

 

[Alice of Old Vincennes]

Even on a Honda he rides tall in the saddle.

View attachment 60930

I rode that bike in 1970!

 

[Doodski]

Even on a Honda he rides tall in the saddle.

View attachment 60930

The Duke was 193 cm (6 ft 4 in). I just love the, "Send'em to hell." movie quote.

 

[Alice of Old Vincennes]

The Duke was 193 cm (6 ft 4 in). I just love the, "Send'em to hell." movie quote.

Thank God I am only 6' 1" At that time I though I looked cool.

 

[Doodski]

Thank God I am only 6' 1" At that time I though I looked cool.

I've had 3 Hondas and they where all cool!

 

[3dbinCanada]

OK, so about forty years ago I watched a fuse pulsate to the bass beats in an amplifier. It was a fuse in line with the speaker, and for speaker protection.

Fuses react to current flow and they heat up when it happens. Now, I don't think I heard the affects of this fuse whose impedance was increasing on each surge of bass current to the speaker, but it is a varying resistance and so it will also affect lower energy but higher frequency pulses going through it (that is a higher impedance (impedance resists current flow or restricts it)would therefore encounter more impedance than if the fuse impedance was not changing. What I mean is lower energy signals will be impeded more by this higher impedance state of the fuse on those bass notes that "pulsate" the fuse.

So, yes, anything in line with the signal can affect the signal or sound. This pulsation is also not linear, so that also can affect the sound.

That's pretty much a short summings up on fuses in the audio path.

I do not say that any so called audiophile fuses are any better, I will say that if the fuse is not used directly in the audio circuit path, (ie it is used in the incoming mains ac power) it is highly unlikely to have any audible improvement for even the most golden of golden ears and I would place some money on those bets any day of the week.

What is the magnitude of this resistance change once the fuse is warm? The fuse itself is not pulsing but the current source through it is pulsing.

 

[Doodski]

What is the magnitude of this resistance change once the fuse is warm? The fuse itself is not pulsing but the current source through it is pulsing.

However you dice and slice it... the power is enough to make light and pulsate while doing that. >@^_*@<

 

[mansr]

What is the magnitude of this resistance change once the fuse is warm? The fuse itself is not pulsing but the current source through it is pulsing.

Fuse datasheets typically specify cold resistance and maximum voltage drop at the rated current. A Bussman S500 series 10 A fuse (a popular choice at Farnell) has a cold resistance of 8 mΩ and max voltage drop of 120 mV. Ohm's law gives the maximum resistance as 12 mΩ. Lower current ratings have higher resistance, the 1 A variant going from 125 mΩ to 200 mΩ.

If we're talking about mains fuses, the resistance is immaterial. When the rectified input charges the filter capacitors, current is drawn in pulses at the peaks of the voltage waveform. A fuse has enough thermal mass that it doesn't cool off (much) between these pulses. In fact, it typically takes several hundred milliseconds or even several seconds at the rated current for the fuse to blow. Even if there is some variation in fuse resistance over longer time intervals, this does not affect the operation of a reasonable power supply which has to cope with fluctuating mains voltage anyway.

Fuses in the signal path are obviously better positioned to affect the sound. Suppose the fuse is placed at the output of an amplifier intended to deliver 100 W into 8 Ω. A fuse rating of 10 A would be reasonable here. As we have seen, such fuses have a resistance of 10 mΩ or so with a variation of a few mΩ between cold and rated current. Remember that the voice coil of the speaker also heats up with use, thus changing its resistance, probably orders of magnitude more than the fuse, and this too pales in comparison with the distortion inherent in the speaker anyway. In light of this, I do not think fuse-induced distortion is anything to be worried about.

 

[3dbinCanada]

Fuse datasheets typically specify cold resistance and maximum voltage drop at the rated current. A Bussman S500 series 10 A fuse (a popular choice at Farnell) has a cold resistance of 8 mΩ and max voltage drop of 120 mV. Ohm's law gives the maximum resistance as 12 mΩ. Lower current ratings have higher resistance, the 1 A variant going from 125 mΩ to 200 mΩ.

If we're talking about mains fuses, the resistance is immaterial. When the rectified input charges the filter capacitors, current is drawn in pulses at the peaks of the voltage waveform. A fuse has enough thermal mass that it doesn't cool off (much) between these pulses. In fact, it typically takes several hundred milliseconds or even several seconds at the rated current for the fuse to blow. Even if there is some variation in fuse resistance over longer time intervals, this does not affect the operation of a reasonable power supply which has to cope with fluctuating mains voltage anyway.

Fuses in the signal path are obviously better positioned to affect the sound. Suppose the fuse is placed at the output of an amplifier intended to deliver 100 W into 8 Ω. A fuse rating of 10 A would be reasonable here. As we have seen, such fuses have a resistance of 10 mΩ or so with a variation of a few mΩ between cold and rated current. Remember that the voice coil of the speaker also heats up with use, thus changing its resistance, probably orders of magnitude more than the fuse, and this too pales in comparison with the distortion inherent in the speaker anyway. In light of this, I do not think fuse-induced distortion is anything to be worried about.

Thanks for that because post 29 incorrectly asserts that at low frequencies, the fuse will get heated and cooled down by the wave . There is no mention of thermal resistance in that post and current flowing either direction has no cool down affect.

A 10milliohm resistance is so low a resistance that the voltage across the fuse is negligble. Most people cannot discern a .5db increase in loudness. Assuming an amp can crank out 10 amps, the voltage drop across the fuse is 100mv compared to 80 volts across the (assuming 8 ohm purely resistive) the speaker terminals. Thats -58db down . No one is going to hear that.

 

[3dbinCanada]

However you dice and slice it... the power is enough to make light and pulsate while doing that. >@^_*@<

I dont read hieroglyphics ...

 

[Cbdb2]

Thanks for that because post 29 incorrectly asserts that at low frequencies, the fuse will get heated and cooled down by the wave . There is no mention of thermal resistance in that post and current flowing either direction has no cool down affect.

A 10milliohm resistance is so low a resistance that the voltage across the fuse is negligble. Most people cannot discern a .5db increase in loudness. Assuming an amp can crank out 10 amps, the voltage drop across the fuse is 100mv compared to 80 volts across the (assuming 8 ohm purely resistive) the speaker terminals. Thats -58db down . No one is going to hear that.

Its the change in fuse resistance with temp. that causes distortion not the resistance. The relatively long thermal constant ( temp changes slowly compared to the signal ) of the fuse means the temp chages with a music signal ( fairly constant power) will be very small, so will the distortion. Your speaker wire probably has more resistance than the fuse.

 

[Cbdb2]

Thanks for that because post 29 incorrectly asserts that at low frequencies, the fuse will get heated and cooled down by the wave . There is no mention of thermal resistance in that post and current flowing either direction has no cool down affect.

A 10milliohm resistance is so low a resistance that the voltage across the fuse is negligble. Most people cannot discern a .5db increase in loudness. Assuming an amp can crank out 10 amps, the voltage drop across the fuse is 100mv compared to 80 volts across the (assuming 8 ohm purely resistive) the speaker terminals. Thats -58db down . No one is going to hear that.

Its the change in fuse resistance with temp. that causes distortion not the resistance. The relatively long thermal constant ( temp changes slowly compared to the signal ) of the fuse means the temp chages with a music signal ( fairly constant power) will be very small, so will the distortion. Your speaker wire probably has more resistance than the fuse.

 

[Pjetrof]

Ok ok ok, I finally found peace, that amplifiers are inaudible, after 30 years of unrest, unsecured of myself, I never heard diffrence between amps, between CD players, between cables, only when they changed the speaker I heard a diffrence, and only when speaker changed from box to planar speaker for example, or when the way how speaker is build for example Harbeth vs no resonant box, I hope I explained myself right, maybe I am exaggerating a bit, but the difrence between speakers from same type was for my hearing even not night and day, but little diffrence. But all the other stuff amps cables etc etc etc no diffrence, and I agreed with all the salesman said and everything I read on forum uf course the golden amp from 40 kg over 10k euros or dollars sounded much better, uf course the cable thick as my car sounded much better. uf course the electric wire as thick as my fist made diffrence, even that the electric for thousand of km or mile is running through wires much much smaller. Now fuses for f..k S..ke why should they sound differen. When I drink a bottle of wine my system sound different! Not when I change fuse cable Dac amp only when I change speaker the room carpet painting etc etc Now I know lots of BS! Be happy instead of buying a fuse. Take a beer and donate the rest of the money to people who really need it. There are kids today dying from hunger! I made the same mistake spend lots of money just to say I have this or that only cause other people and magazines and forum say it sound better! It doesn’t !!! I m ashamed throwing so much money away. People can spend money on cars etc on art etc but there it’s obvious and measurements show that one car is better than an other one painting I like better. But if the goal is good sound, that is the only reason why people buy music systems to hear music. It’s ridiculous to spend all that money and then justify by saying it sound so much better! I did it myself 30 years god thx I found ASR.

 

[3dbinCanada]

Its the change in fuse resistance with temp. that causes distortion not the resistance. The relatively long thermal constant ( temp changes slowly compared to the signal ) of the fuse means the temp chages with a music signal ( fairly constant power) will be very small, so will the distortion. Your speaker wire probably has more resistance than the fuse.

This resistance range of change will show up as -58db to -58.1 or -58.3 etc.. What I'm pointing out is that voltage amplitude change is soooo very small across the fuse compared to the amplitude of the signal that its impossible for human ears to pick it up. Its analogous to me talking to you in a normal voice 100ft away during a "Who" concert in full bore.

 

[mansr]

Its the change in fuse resistance with temp. that causes distortion not the resistance. The relatively long thermal constant ( temp changes slowly compared to the signal ) of the fuse means the temp chages with a music signal ( fairly constant power) will be very small, so will the distortion. Your speaker wire probably has more resistance than the fuse.

The speaker wire likely has higher resistance, but since it doesn't heat up, its resistance is constant. The fuse does warm up, but not quickly enough to track each peak of the waveform. Rather, it follows the short-term average loudness. If the music goes from a quiet to a loud part, the fuse will indeed warm up a little, and as a result increase its resistance by a few mΩ. Compared to the total resistance in the speaker circuit, this is negligible. Any effect it does have will be a very, very slight dynamic range compression. Nothing to worry about.

 

[Speedskater]

to repeat from my post #8:

Moving on, Bob Cordell is his great book "Designing Audio Power Amplifies" did measure fuse THD in an audio output stage.
It's section '13.11 Fuse, Relay and Connector Distortion' page 268.
Conclusion:
"At 20 Hz, amplifier distortion due to the fuse is calculated to be 0.0033 %."

Note that at frequencies above 20 Hz, there will be less THD. Even at 20 Hz, it was not easy to measure.

 

[Bob-23]

Sorry, calculation was wrong - it's too late for maths... Nontheless I think it's inaudible.