Power amp current source reserve requirements
When you try to understand how commercial amps work from reputable Japanese designs, and see the purpose of each component, you may learn how to improve quality.



Of course there are many details in thermal matching and hFE binning needed as well.  Here TR110 acts as the Vbe multiplier which must be thermally attached to the output stages.  Tuning is performed with Pot VR101.

There is also OCP output protection with TR113,114 with 0.47R sense and OVP input protection with diodes and 47pF and an input RC complex network for spectral coupling and noise rejection.

Each component here is carefully selected for many reasons with careful selection of caps for transient input and load response.

Next is a similar one from the same company, slightly newer.