amp power rail fuse

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I use car fuses with the push in blades, as they are rated to break DC currents.
One use of output fuse is to protect crowbar (triac) protection circuits. The theory is that DC on output would cause the crowbar to trip the mains breaker on the amp. Actually my purchased amp would melt the protection triac off the board, burning lands, and produce DC on speaker for as long as the power switch was on. Output fuse ahead of triac should prevent that.
 
If you want to experiment with sound of fuses for cheap, try building your own with strands of your favorite wire. Glass fuses are easy to modify. The quickest way I found is to drill 1mm holes into the cap centers, remove the existing wire, put your new wire through the holes and solder on both ends.

But it's a must to test strands for current capability before building.
 
Car fuses sounds good. What's this ceramic body silica sand filled fuse ?
Btw do you hear sound differences when compared to normal glass fuse.

Thanks guys
The purpose of the silica sand is to prevent metal vapor depositing as a conductive layer on the inside of the tube.
I find that the silica sand filled fuses sound different to, and to me preferable to standard glass fuses....cleaner, clearer and more pleasant 'tone' IMO/IME.
Also, use T (Time Delay...NOT Slow Blow) type fuses....these are intermediate speed and allow intermittent higher currents than standard Fast type fuses.

Dan.
 
The output transistor is likely to blow faster than the fuse, so it is actually the transistor that protects the fuse.
And, as said, once blown at one rail, DC from the other rail is likely to blow the speaker too.
IMO fuses are useless, speaker protection does make sense when using expensive speakers.

I like this here...
Fuse the primaries and kill mains on DC sensing.
Skip the rail fuses
 
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