[Amarok]

Abstract: Blew a fuse and can't tell if it's a fast or slow blow.
I can see that it's 1,6A 250V and ceramic.
Does anyone know fast vs slow?

The amp worked fine the night before. I turned it off right after listening,
so I know it was good then. But nada next time I tried. But there were no
signs of anything amiss when I powered it up. Other than no power LED.

I found the fuse holder and pulled the fuse. Hmmm... ceramic. On the opaque
side. Hard to tell if it's blown. There probably is an easy way to check it,
but I hauled out the DVM and sure enough, infinite resistance. Using my
handy STM, I read 1,6A 250V. But couldn't tell the blow-ed-ness. But given
the two soup can sized caps on the MPX3, I figured slow blow. And my Cary
has slow-blows, too.
I got some fuses at Radio Shack, but all they had were fast blow. So I tried
'em and poof! The wire was vaporized.
So, hopefully that was because the amp needs slow-blows and not a sign of a
larger problem.

 

[daggerlee]

The fuse blew too in my vintage SP MPX3, and mine was a fast blow. It was because the power switch had gotten shot during shipment, I replaced it and the fuse and everything work.

It's best to figure out what exactly caused the blow before you start replacing fuses...it's not a matter of whether or not the MPX3 will work with fast blow fuses or not, but a matter of what's causing the short...at least that's how it worked out for me.

 

[sacd lover]

I would call SP. That fuse size seems to low. I think my MPX3 has a 2.5 amp slow blow.

 

[Rob N]

The fuses in the 230v models are 2A

 

[Amarok]

I called Singlepower and they're gonna send me out a few.
We also had a nice discussion about how (other than the fuse thing the
amp's working out for me, how it sounds with the other equipment I have,
etc. It is a very nice company to work with.

The fuse was rated too low, which we're assuming is the reason for the
blowage. For the record, the MPX3 fuse, for US amps is:
2.15A, 250V slow-blow.

The best sounding ones are the unglazed peruvian ceramic, braided nano-tube
element and dual YBCO end caps.

Radio Shack ones are rumored to sound just as good.

-=A=-