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An argument for fuses and maybe power cables in power amplifier

There are a lot of discussion about fuse but I don't remember a thread that include

an actual circuit.

The circuit below is called a rectifier which converts AC voltage from the wall to DC voltage that feeds to audio power amplifier.  All if not most power audio amplifier uses this topology.  Some have bigger transformer, some have more capacitors, some have higher voltage output but most are more or less the same.  Audio amplifer uses a lot of current so they don't use a regular which may even degrade the supply, therefore most will just use what you see below as a rectifier circuit.

You can see from the circuit the current comes from the wall, the AC source far left, to the fuse, F1 5A upper left, go through the transformer then to the diode rectifier, D1 D2 D3 D4, then finally to the 25+/- supply source which then will feed to the power audio amplifier.  

So you can see the fuse is clearly in the signal path.

As for the power cable, it is harder to understand.  Most power cable are already  beefy enough to handle the current so having an even beefier cable will help is something that needs further reasoning.

andy2
asvjerry's avatar
asvjerry
4,556 posts
 

"DeeeKay, have it Your Way!"

Ah...ASCII Art....been awhile... I remember when we used to chisel that into the nooks 'n crannies to confuse the archaic-ologists and please the tinfoil hat crowd....

Now?  ....just type...*sigh*....

Better laughs to chisel in "Don't move this block!" on a face; on the opposite side, "See? Told you....'nuthin'."  just before it would tip over onto them....

PP.....Pyramid Pranked.
​​Y​​​eah, @rodman99999....the good old days....

"Exponentially speaking typing, you must be pretty high by now... ;) 

BTW, Dr. Whiplash was a 'proprietor' of  a "Miracule! Liniment! that will cure Everything from muscle ache and pulls, gout, headache, heartache, ..."

I've got nearly enough line power cords to nearly knit a net with pool cues (some smart*ss wrote a book on the subject....honest! )
Given all the high-level attention given to an item that spends a lot of its' time on floors for the most part.....

As noted: 

 

if it's not for such as this...for me, perhaps you, with this little ditty from the DB's....

 

                                               why?

 

...best of your days, J

 

 

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smg62
3 posts
 

As an electronic design engineer I will say that if the power cord and fuse makes a difference in the amplifiers performance then the amplifier has not been designed with the proper margin.  If designed correctly the AC to DC conversion in the amplifier should have margin for line voltage variation, energy storage (caps) and so-on.  Surge protection is another must have.  

andy2 OP
1,545 posts
 

^^^ On the other hand, on a poorly design AC-DC conversion amplifier, it will be the bottle neck therefore a power cable or fuse would not make a difference.

For example on a cheap Japanese receiver, I doubt the fuse or power cable would make a difference.

rodman99999
6,107 posts
 

@andy2 -

                                                         +1

       Very little to nothing can be done*; to improve the sound of truly inferior audio components.

        *nor: To dispel the lingering miasma of a Denyin'tologist and the severely limited 19th Century Electrical Theory, to which they cling.

                                                 Happy listening!

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