"Nazar`s regulator", variants

A couple of variants of this ideal regulator for audio applications.

Ideal because:

• Stable and small output impedance in the 20-20kHz area and above (for 2x trans. version ~ 0.05ohm and ~0.005ohm for 3x trans. version).

• Load current flows locally through the regulator`s output transistor only.

• Excellent step response.

• Little capacity electrolytic cap on regulator output or no electrolytic capacitor at all.

Also

• High PSRR (for 2x trans. version 100db and 120db for 3x trans. version).

• Low noise < 1uV (20-20000hz).

• Simple and reliable.

• No global negative feedback.

In addition to the classical 2x transistor "nazar`s regulator" also described 3x transistor version characterized by much better output impedance and PSRR.

Also described a filter/voltage follower that makes better use of supply voltage (Uout = Uin-0.7V) and have a higher efficiency. This is possible thanks to the fact that the majority of audio circuits don't need stable voltage psu.

Simulation results of the output impedance, PSRR and step response for LM317, 2x transistor "nazar`s regulator", 3x transistor "nazar`s regulator", filter/voltage follower and LT1761 are attached below.

Green graphs are for LM317, red for 2x transistor "nazar`s regulator", cyan for 3x transistor "nazar`s regulator", blue for filter/voltage follower, magenta for LT1761.

LTspice simulations files

"Directly or indirectly, all questions connected with this subject must come for decision to the ear, as the organ of hearing; and from it there can be no appeal" J.W.S. Rayleigh