What kills a valve rectifier?

For the most part, that's accepted, and if a component has failed in a way that it obviously shouldn't have, then of course the reason behind the failure should be investigated and understood. But in the case of valves with an obvious internal mechanical failure, it's just that - a dud valve ...

Agreed, but that does not make it 'right' in terms of minimising the stress on the valve's internal structure. I guess that upside down is better than on their sides, but I still prefer to see power output valves and rectifiers, being run upright.

I would have said not, but who knows ?

Arfa

If the iron is able to handle it I've known it to be a preferred replacement for those who want some more sag. Especially harmonica players.

Not for those looking for more sag. I have a couple clients running variacs to get that kind of sag sound with a GZ tube.

I've installed several SS diode replacements for a valve rectifier. Most notably the RTSSR from Ruby. Some musicians like sag in their amps and you certainly won't get it from the RTSSR or a 5AR4.

It TOTALLY depends on the musician and I always cater to their ears.

"Arfa Daily"

Say the winding is rated at 5 volts and 2 amps to suit a 5AR4 and the copper wire is gauged to give about 10 % regulation factor. Then the heat loss in the 5 volt winding is 10% of the load power or about 1 watt.

If a 5U4 is subbed - the extra 1.1 amps will mean that 5.0 volts drops to

The extra heat in the winding amounts to 0.8 watts - which is trivial in a tranny designed to lose 15 to 30 watts as heat in normal operation.

..... Phil

Good to see the real Phil back for a little while.