"Is this all mean that for audio use, classical simple current mirror like Subwo1 use , consisting only 2 transistor, with bases attached to each other and attached to one of collector is good enough?"
I've fiddled with improved current mirrors and while many show some improvement in simulation, the improvement ocurrs so many decimal places to the right that I doubt all bur the most expensive test hear could measure it. Like improving distrotion fro .005 to .00495. And if you don't care for measurement I report that subjectively I could hear no difference. The key masy be that I can generally go through a bad of 2n5551's or MPSA42's and find either exact matches or at least within 2%. Hence circuitry to compensate for a poor match doesn't have much to compensate.
I think there are probably special cases where the enhancements are important - but not usually.
I've fiddled with improved current mirrors and while many show some improvement in simulation, the improvement ocurrs so many decimal places to the right that I doubt all bur the most expensive test hear could measure it. Like improving distrotion fro .005 to .00495. And if you don't care for measurement I report that subjectively I could hear no difference. The key masy be that I can generally go through a bad of 2n5551's or MPSA42's and find either exact matches or at least within 2%. Hence circuitry to compensate for a poor match doesn't have much to compensate.
I think there are probably special cases where the enhancements are important - but not usually.