SAD

[Hoochie Coochie Man]

Recommended settings for the best sound is to set the gain, and eq knobs to max. Next, turn up the master vol until flames are shooting out of the amp, and then back off just a little bit. They probably just neglected to do the last step.

 

[Bassmec]

This is all the spares you need right here.

 

[meatwad]

Just spray some contact cleaner in the jacks...

 

[subdude67]

so, what exactly seems to be the problem?

 

[WaldoNova]

That's what happens when you use a 115 and a 410...

 

[beans-on-toast]

I was wondering if someone plugged a power amp out from another amp into the speaker output. There's a lot of damage.

 

[danosix]

Maybe not the best amp for metal?

I dunno - I think this is the perfect amp for metal... (ie silent) .

 

[danosix]

First, let me make it clear that I'm not blaming the caps for what happened here. It doesn't look like they blew.



OK, I'm just a little surprised to hear that (though I'm not surprised that you might prefer 63V caps - if you were going to put your name on this amp, would that "might" become more definite?). I've always read that 10% over nominal operating voltage was an absolute minimum, and I'd expect GK to do more than that. Most higher-end amps that I've seen have more like 20-25% headroom in the voltage spec for the first stage filter caps, some have more.

Of course there are a lot of those amps still working fine. I didn't say it was too low, I said "cutting it close", which I still think it is.

Reid

Actually, 50 is 10% over 45.

 

[Slevage]

Maybe the owner hooked up all of the speakers in his arsenal to see how it would sound.

That's what happens in a parallel universe.

 

[Marial]

Is that a Lucas? Makers of the only vacuum that didn't suck...

 

[ZonieBass]

Looks like he was using a 10 gauge no blow fuse.

 

[29A]

First the good news: Your fuse is fine.

Hilarious!

 

[Coolhandjjl]

I love the smell of FR4 in the morning!

 

[Hoochie Coochie Man]

I see the circuit board is a through-hole design. One advantage of surface-mount technology, is that, (depending on the orientation of the board to gravity), the components that get real hot will unsolder themselves, and just fall off the board. That's why I always run my PF-500 upside-down. Just in case. Ya know?

 

[guitar ed]

Don't forget to check the Flux Capacitor.

edg

 

[BurningSkies]

Is this one of those amps they say you can hose down to clean them out...as long as you let them dry thoroughly before testing? Maybe that's an option.

 

[eukatheude]

Maybe the owner hooked up all of the speakers in his arsenal to see how it would sound.

That's what happens in a parallel universe.

If it was a series universe, instead, it wouldn't have happened.

 

[BioWeapon]

Actually, voltage rating is very closely related to power output. For a typical class AB amp (and this is not a particularly exotic design as far as I can tell), power output into 8 ohms is determined mainly by the rail voltages (current-carrying capacity of the output devices typically limits power into lower impedances). Rail voltages determine the required voltage rating of the filter caps, and a 100W amp using typical output devices (such as the TIP 36C seen here) will have rail voltages around +/-45V, as agedhorse notes above. I'll reply to his message separetely.

As for being designed by professionals, well, yeah, no kidding, but compromises get made in any product. We aren't talking about a cost-is-no-object, bulletproof mil-spec design here. You can look at almost any mainstream audio product - designed by professionals - and point to areas that aren't very tolerant of over-voltage.

Reid

It seems I'm not as informed as I had thought
It seemed more logical for me to think that the circuit could be designed to use any voltage, and that circuit topology and design along with current would determine output impedance and power. Hence why some amps run on 40v, 250v, or 12v (eg solid state, tube, and car-specific amps). But then, I have no formal education where circuitry is involved. Eventually I will, but not yet!

 

[Thomas Kievit]

If it start smoking again, throw it in a river : Smoke On The Water

 

[PullThePlug]

Good thing a fuse replacement is cheap