Choke power supply- part 2

Back in 2008 I asked why choke power supplies were not more common. At the time, the majority of opinions were that choke power supplies were more expensive and so most manufacturer's chose not to use them. Today, with mega priced gear, I still question why manufactures are not more enamored of using them in their power supplies?

I am of the opinion that a choke power supply can sound spectacular and it does seem to offer several technical why not more popular? Surely if it is still cost, that seems to make less sense as the price of top flite gear is now approaching six plus figures! Thoughts?


That fooled me for a minute, didn't realize I needed to scroll down on the pictures for Pic 5.  I'm really curious about this upcoming amp from Schiit.  They have been employing a lot of innovative circuitry(at least innovative to this guy) over the years in their headphone amps and dacs.

I'd not even heard about a choke power supply.  I passed on the Aegir amp, since it was only 20 wpc and wouldn't work with my speakers, and the Vidar has been better than my Adcom amps.

This new amp, I think they call it the "Tyr", I would really take a hard look at.  200 wpc, monoblock, they say it's the best sounding amp they've made.  I think I'd have to sell off the Adcoms...  

@daveyf ,


The first question would be do you know what a choke power supply is?

More accurately would be a choke filtered power supply, with a few different variants.


Why not?  Other than the cost and bulk, there is the question of whether they are the best implementation.

That said, most linear power supplies have some choke filtering, just for high frequencies.

Output of a bridge rectifier is DC + harmonics of twice the AC frequency. The choke in combination with the capacitor forms filter eliminating some of those harmonics, but the choke in combination with the load does as well. Hence, the output voltage can droop. So much for your high dollar, low resistance AC power cord.

To get enough inductance to be useful, you need a large inductance which means materials that are not great at high frequency. So at that point, do I really want the big inductor, or should I go for s smaller inductor and burn off a bit of power with a linear regulator? The best answer is always trade off the properties for the best overall implementation.

@cindyment  I hope you understand a linear power supply is to create a DC voltage and current out of a 60 hz AC line. One would not want it to pass high frequencies. The OP is posting about a choke input PS, which is considered to be a step above an ordinary supply using chokes and caps after rectification.

Whether you put the choke on the input or the output the effect is the same. A transformer reflects the impedance from one side to the other based on the turns ratio. Even if the inductor is on the front AC side, it still effectively forms an LC with the capacitor. Note Schiit's Description. It works, but is it is a good engineering idea? Questionable.  The "custom nickel core" sounds all impressive, but that is just common core material and custom inductor is not remotely difficult.


And pure LC—inductor-capacitor filtering from the highest to the lowest band, including 4 custom 80% nickel-core inductors as big as 1.5 Henries. 

Well apparently Schiit figured out a way to make it a "good engineering idea" without checking with cindyment.  Mike Moffat and Jason Stoddard have been designing/engineering amplifiers and dacs since the '90's, so they might know a thing or two about it.