What is a class G amp ?

Here is some reading :

http://en.wikipedia.org/wiki/Electronic_amplifier

I had a Class G Hitachi SR-804 receiver I bought in 1978 for years. It was a good but not outstanding sounding piece. Not familiar with the Arcam though.

Hadn't heard about Class G in years.

Class G enables higher peak power delivery in a smaller package compared to Class A/B is my understanding.

Newer Class D amps are the more popular amp technology it seems these days for those looking for more bang in a smaller package along with lower acquisition costs and power consumption benefits.

Often class G would be used in portable headphone amps. On rechargeable lithium battery these little ones can last upto 30 hours of continuous listening. It has advantages over A/B class almost on every aspect you can ever think of including clarity, noise floor and certainly efficiency. Call it improved class D.