Would it be possible to start the filtering chain after the rectifier bridge with a resistor (or with a choke), right before the first reservoir capacitor? My goal is less hum at the output of the B+ power supply, and perhaps also avoiding a snubber.
Hi,
Yes that is possible. You can even put resistors before and after the diode bridge. The effect is to limit the current somewhat thereby reducing peak current and ringing in the diodes. Did that quite a lot in combination with average 1n400x diodes (aka 'a slow diode bridge'). The effect depends on the circuit. On a power amp you could try 0.1R and 10-100R on pre amp circuits and such.
Using a choke gives added benefits (search choke input) if calculated correctly. The main benefit is better attenuation of ac ripple on the psu line, less humm.
regards
Joris
Yes that is possible. You can even put resistors before and after the diode bridge. The effect is to limit the current somewhat thereby reducing peak current and ringing in the diodes. Did that quite a lot in combination with average 1n400x diodes (aka 'a slow diode bridge'). The effect depends on the circuit. On a power amp you could try 0.1R and 10-100R on pre amp circuits and such.
Using a choke gives added benefits (search choke input) if calculated correctly. The main benefit is better attenuation of ac ripple on the psu line, less humm.
regards
Joris