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RE: How do you represent your tubes in PSUD2?

Posted by Tre' on May 29, 2017 at 20:50:44:

"The amount of voltage sag remains the same, so regulation is the same."
We might be talking about two different things but I don't think the above is true. I am talking about a supply that Dennis Fraker would use.
A supply filter built to take longer to "stabilize" after a current draw change will be less regulated if the current draw increase (or decrease) is sustained. The chokes will be bigger with more DCR and the caps would be bigger.
If the supply is operating a Class A circuit then the only thing that will cause the current to increase or decrease from the idle current is the music.
BTW the current will never increase (or decrease) instantaneously as it does with the "stepped response" feature in PSUD2. It will, instead, follow the music and it will take time for the current to increase and decrease.
The longest duration the current will increase (or decrease) due to the music is 12.5ms ( 1/4 of a 20Hz wave cycle) before it heads the other way.
If you look real close to a supply designed to stabilize quickly vs a traditional power supply I think you will find that in the first 12.5ms the traditional (slow) supply dips (or soars) less.
Looking a sims of each, the "fast" supply dips 2 volts in the first 12.5ms and the traditional (slow) supply dips only .27 volts in the first 12.5ms
(I admit the two supplies are different, one is a 464 volt supply and the other is 530 volts but I think my conclusion is valid)
Now if the current increase were sustained the traditional supply dips 4.5 volts and the fast supply dips only 2.75 volts for a current increase from 60ma to 70ma. but Class A amplifiers playing music don't do that.
As I said, we might be talking about two different things.
Tre'