An Early LSES Experiment

Triad C40X LSES Power Supply Filter Experiment

This SE 6AQ5 amplifier was one of my first experiments with LSES power supply filtering.

The time line must have been around the of Fall 2008.

Jeff Medwin aka Drlowmu encouraged me to try some Triad C40X filter chokes in an LSES power supply filter for my amplifier. 

I don't think JM ever used these parts before, not did his mentor Dennis Fraker.  

The recommendation was based on having experience with a Stancor choke that had similar specifications.  That seemed reasonable advice at the time.

My circuit featured 6AQ5 triode connected finals driven by a resistor loaded 6SL7 twin triode. The two stages were cap coupled. The tube rectifier is a 5U4G. Power output at onset of clipping was probably 3/4W.

Unfortunately, the Triad C40X did not function properly as an L1 choke in an LSES filter.

The chokes developed a mechanical buzzing sound even with the modest current requirements  of my humble circuit.  I doubt that I was running 60-70mADC, probably it was less than that.

I must say that the Triad C40X chokes can function well in low DCR filter circuits if they are not used as an input choke. 

DT 667