In ss gear it’s all about bias current. my 2 mono 100watt class a amps cost about 125 bucks a month towards the power Bill Why. Cuz that’s what it takes to have such high bias . If it’s real class A they will be very heavy and get very hot. It’s a horribly inefficient . Mine are basically like having a hair dryer going 24/7. At idle.
In a Nelson pass design the A to AB kicks in once the output current goes more than double the bias current. that’s right off passlabs web page as to how they explain their rating system. ,It’s misleading to say they are class A, They are AB. Step up to Amps like Boulder which are true class A and they weigh hundreds of pounds and will set you back the price of a sports car for a small one or house for higher powered amps. It takes heavier components to maintain such high bias current in ss gear.
Which is why tube amps amps are awesome and can be low wattage and give out true class A albeit just a few watts and still be in most peoples realm of affordability.
In a Nelson pass design the A to AB kicks in once the output current goes more than double the bias current. that’s right off passlabs web page as to how they explain their rating system. ,It’s misleading to say they are class A, They are AB. Step up to Amps like Boulder which are true class A and they weigh hundreds of pounds and will set you back the price of a sports car for a small one or house for higher powered amps. It takes heavier components to maintain such high bias current in ss gear.
Which is why tube amps amps are awesome and can be low wattage and give out true class A albeit just a few watts and still be in most peoples realm of affordability.