Class-AB amplifier
TL;DR
Class-AB is the traditional linear amplifier topology in vintage receivers and most non-Class-D integrateds. Roughly 50% efficient, warm sound, mid-range weight and dynamic drive - the "classic hi-fi sound".
Class-AB is a hybrid topology where output transistors conduct most (but not all) of the audio waveform. It combines much of Class-A’s linearity with better efficiency than pure Class-A.
Trade-offs
- ~50% efficient – noticeably cooler than Class-A, hotter than Class-D
- Slight crossover distortion at the zero-crossing point (much less than pure Class-B)
- Warm, forgiving sound signature preferred by many vintage-gear enthusiasts
Where you’ll find it
Every vintage receiver from the 70s-90s: Sony ES, Marantz, McIntosh, Adcom, Denon. Modern integrateds from Yamaha (A-S series), NAD, Cambridge Audio. Owners feeding these amps from a AIYIMA A80 as preamp get the best of both worlds.
Ready to see this in action?
Browse honest, hands-on reviews of budget hi-fi gear that puts these concepts to the test.
