Tube rectifier effect...

[EFK]

This may sound stupid and if so please tell me! Does a tube rectifier impart any tonal effect other than voltage sag? In other words, does the power being run through the tube itself effect the tone of the amp?

I'm familiar with mounting diodes on the tube rec as a safety or backup feature, but is it possible to somehow create a diode rectifier that runs the power through the tube regardless of whether the tube is actually functioning? For example, an amp with no 5V filament winding in the PT. I realize you could just internally jumper the diodes to pin 8 on a rec socket and run it with no tube at all, but what happens if there is a tube in the socket as well with no functioning heaters? Is it just window dressing? Or does it short something out? Does it create any *noticeable* difference in sound? Just thinking out loud.

[tubeswell]

This may sound stupid and if so please tell me! Does a tube rectifier impart any tonal effect other than voltage sag? In other words, does the power being run through the tube itself effect the tone of the amp?

I'm familiar with mounting diodes on the tube rec as a safety or backup feature, but is it possible to somehow create a diode rectifier that runs the power through the tube regardless of whether the tube is actually functioning? For example, an amp with no 5V filament winding in the PT. I realize you could just internally jumper the diodes to pin 8 on a rec socket and run it with no tube at all, but what happens if there is a tube in the socket as well with no functioning heaters? Is it just window dressing? Or does it short something out? Does it create any *noticeable* difference in sound? Just thinking out loud.

If the tubes heaters aren't functioning, the tube won't work.

Also, the diodes cathodes have to be connected eventually in order for diodes to provide 'continuous' rectified voltage to the filter. So unless there was something in the tube shorting both pins 4 and 6 to pin 8, then those 'back-up' diodes (i.e.; the ones between the HT winding and the tubes anodes/pins 4 & 6) won't do the job either.

[Diablo]

Think of a tube rectifier as a pair of diodes with a resistor in series and a switch. The switch is the cloud of electrons that conduct across the vacuum inside the tube between the anode and cathode. The heater filaments create the cloud of electrons. If you don't put juice through the heaters, they don't get hot enough to emit electrons and no current can flow between the cathode and anode.

[EFK]

Gotcha! That makes sense.