Help! Did my power cable blow his tube amp?

[sdifox]

I got an infraction here for "Posting in the wrong forum" when I posted in FS/FT with a perfectly good, perfectly serious product that I actually sold on Craigslist for more money later that same day. I did take a crack at overly-paranoid people who may want it (my own potential customers), but the product itself was not a joke. A moderator thought it was a joke and, therefore, thought it belonged in OT. That mod is no longer a moderator but the infraction remains front and center on my profile page. 🙁

err, wrong thread?

 

[CZroe]

err, wrong thread?

Wut? Huh? Yes.

http://forums.anandtech.com/showthread.php?t=2272318

 

[C1]

What makes more sense out of all of this is that the amp owner had (has?) a short circuit on the output side of the amplifyer. This could be anywhere along the output line including the driven sound source (presumably a speaker).

If his amp doesnt have "fast shut down" circuit protection "built in" the output side (and we're talking milliseconds) then that amp could fry its circuit including tubes and fuses out in an instant (hence the need for fast blow in-circuit fusing). (Remember that audio amps are capable of outputting incredible amounts of peak watts.)

I would think that a $10K amp would employ output circuit protection, but that can be sophisticated and might have not been included because it was felt to be detrimental to the purity of the audio as the sensing circuitry has to be involved with sensing in the audio output section.

 

[Railgun]

...perhaps you had a much larger gauge conductors vs. stock cord and amp saw a sudden surge of current it was not designed to withstand?

Definitely not. The unit will use as much current as it wants to the limit of the wiring or the breaker/fuse, it doesn`t get "pushed" to the device. So long as the voltage and polarity, if sensitive to that, are the same, then OK.

Being a tube amp, it is possible that it is sensitive to polarity? I would think yes. But I don`t know how the internals are setup.

 

[AudioTruth]

I wouldn't think so, the cord may feel warm depending on the current though.

According to Wikipedia 14awg can carry 20/20/25 amps at 60/75/90 degrees C rated insulation respectively. They don't show 15awg current ratings, but 16awg was rated at 18a @ 90 degrees C

Ah, so my cable is not too thin then.

If his tube amp is pulling 18 amps then it would nearly have to have its own circuit in his home. Most typical household circuit breakers are 15 or 20 amps.

And if the tube amp would draw more than 15 amp, it would have a different IEC input made for 20 amp plugs?
Today I'm receiving cables with 20 amp plug, I will check.

 

[MagickMan]

That's a scam, ignore him.

 

[AudioTruth]

Ah, so my cable is not too thin then.


And if the tube amp would draw more than 15 amp, it would have a different IEC input made for 20 amp plugs?
Today I'm receiving cables with 20 amp plug, I will check.

Ok, I just received the 20 amp cables, they have a different IEC plug and won't plug into my gear. The 20 amp cables are also quite thin.

 

[SyndromeOCZ]

If your only running a few feet then you don't need much even for 20 amps. Though I like to stick to 12 gauge for all of my personal stuff, I have used smaller many and many times without any issues.