- Jan 18, 2021
- Reaction score
- Staffordshire UK
Why not?I have also never looked at transient/instantaneous peak voltage/current during high demand playing situations.
When you’ve next got an amp on the bench with 1ohm cathode resistors, it’s quicker to do it than to write the above.
Even more illuminating is to scope the waveform, eg blue trace is the VAC across an 8ohm dummy load at the onset of clipping of a Marshall type amp, red trace is the voltage across the 1ohm cathode resistor,
It’s fine until the valve shorts.the low power rating for these should be enough but in reality it aint so
No, they’re fine until the valve shorts.even 1W resistors burn up sooner or later
If there’s a suitably rated fast acting HT fuse in place, then 1/2W should be fine.
If there’s a diode in parallel, then their max dissipation can’t ever get to 1W, so even without a HT fuse, 1W with a diode will be fine when a valve shorts. And in that scenario, that arrangement will dissipate less heat than 5W 1ohm resistors.
As per the Super Reverb RI, see my previous post.
That inrush current flows around the HT winding, rectifier and caps, not via the valve cathodes.Flipping a switch like the STANDBY allows inrush