advertisement


"A" Class amps

Arkless Repairs said:
Solid state is much more reliable, especially power amps, but valve amps are much easier to repair when they do go wrong.... swings and roundabouts.
Click to expand...

Except that most valve power amps do not seem to be a safe one-man lift - my modest SAC KT88 comes in at 30kg.
I suspect the weight aspect might also be a problem with pure class A.
 
uncl_nigel said:
Once is enough...










... to scare the s**t out of you!
Click to expand...

Fair enough, but I have never known a piece of valve euipment to explode or even make much of a bang. I have had smoke, usually from mains transformers (old Cossor scopes get a special mention here) but never any thing frightening. One or two SMPS explosions have been fun though and when the EHT contol on an Eizo monitor let the supply run up to about 40 kV with resultant flashovers all over the main board - well, that caused a colleague to throw his coffee all over the place.
 
uncl_nigel said:
Except that most valve power amps do not seem to be a safe one-man lift - my modest SAC KT88 comes in at 30kg.
I suspect the weight aspect might also be a problem with pure class A.
Click to expand...

60Kg... wus!

Many valve amps actually are class A, especially those under around 40W or so.
 
Barrymagrec said:
Fair enough, but I have never known a piece of valve euipment to explode or even make much of a bang. I have had smoke, usually from mains transformers (old Cossor scopes get a special mention here) but never any thing frightening. One or two SMPS explosions have been fun though and when the EHT contol on an Eizo monitor let the supply run up to about 40 kV with resultant flashovers all over the main board - well, that caused a colleague to throw his coffee all over the place.
Click to expand...

I'm guessing folks are using a bit of poetic license here when referring to stuff "blowing up"... maybe just meaning ceasing to work, possibly with a bit of smoke.
The worst surprises I've had, other than the odd belt from a valve amp.... are the very occasional (thank god!) time when working on a several kilowatt solid state amp and accidentally shorting the PSU with meter probe or plier tip... the bang leaves your ears ringing, the flash gives you that "green blob before the eyes" effect and then there is the molten metal which was once the end of a pair of pliers...

I have seen a loudspeaker burst into flames (around the dust cap in the woofer) when a big S/S amp has gone DC :eek:
 
Zener makes a fair point.

I have an Electrocompaniet Class A amp. Left it on once while I went on holiday. Cost a fortune.
 
You must log in or register to reply here.


advertisement


Back
Top