Resistor-Input vs. Choke-Input vs. Cap.Multip.

[gnomus]

Choke inputs do a lot of good things.

If the choke is big enough than you can expect.( No particular order here just what pops into my head)

Perfect for class A constant current draw. This reduces the size of the choke needed when compared to AB types.

Inrush current reducton. Yank out those skinny wired themisters.

Big reduction in ripple. You actually get a sinwave (100 or 120HzUS) and not the usual saw-tooth tiger. Which is actual noise when you think about it.

You will not know your amp is turned. That's how quite it can get.

Lower capacitor input ripple. Which may increase capacitor life due to lower ripple current across it. Can you hear your caps say thank you?

Reduction of peak diode and transformer current. They will thank you too. Lowered current also results in lowered transformer losses.

You loose voltage, but current is near the full theoretical limit of the AC/VA rating of the power transformer.

Cooler diode and transformer temperatures. Thanks again!

Acts like a regulator. Helping to keep the voltage constant.

Acts as an energy storage device.

Finally it just sounds better. Smooth and musical would be the effect you get. Your basic capacitor input sounds nervous and hyper.

The reason it is not used is increased cost and size. But that is no deterrent for nutty DIY types.

If I missed any please chime in.

[gnomus]

Oh ja, I do not believe inductor wear out like your caps, mosfets, tubes, diodes and ears. They just keep on passing current.

[gnomus]

Also, you may be able to use a smaller transformer and less caps and still get the performance your looking for. This is because of the superior, voltage regulation, ripple filtering and energy storage of the choke. The expense of a choke input power supply can come down. But, we are still stuck with the large size to get all the benefits.

[Blitz]

Paul, I totally agree. I started this threat though to discuss the experiences whcih may or may not be out there to play with resistor-input instead of choke-input and what this gives us. I gues one clear difference is that resistor don't store energy, but destroy engergy, but what does this mean soundwise ?