SMSL SAP-1 Class A headphone amp for 90$?

[MazeFrame]

@BluJay614

Is there a difference between A and AB?

Yes, there is a difference.
Details outlined here:

Amplifier classes

This thread seeks to explain the different amplifier classes in a fashion so you can make a qualified decision about what your application requires. Contents Overview of the amp classes Detailed explanation Bi-Amping, Bridged- & Parallel Amplifier TL;DR Classes overview: Class Construction Advantages Disadvantages Class A Single transistor, full-cycle operation - Very high gain possible - low distortion - low efficency - Requires clean power supply Class B Double transistor pus…