Amplifier Specification questions


I understand the differences between different classes of amplifiers. Most common amplifiers are Class A/B. Does this mean that all class A/B amplifiers operate in Class A to some point then switch over to Class B when they hit a predefined threshold by the design of the manufacturer. Do some so-called Class A/B amps only operate in Class B? My power amp is designed to operate up to 18 watts Class A before changing class of operation. I assume this number is in 8 ohms. My amp is rated at 150 watts into 8 ohms and 300 into 4 ohms. Does this mean that Class A rating will double to 36 watts in 4 ohms or will it stay at 18 watts regardless. What's funny is I was thinking I needed more power because my meters were always pretty well deflected but after looking closer, I realized the meters were on the 5-WATT scale instead of the 150-WATT scale. I can't believe I never noticed that before.

willywonka

@willywonka Wrote:

 Most common amplifiers are Class A/B. Does this mean that all class A/B amplifiers operate in Class A to some point then switch over to Class B when they hit a predefined threshold by the design of the manufacturer.

Yes! See article below:

Mike

https://www.sound-au.com/class-a.htm

And companies rate things differently. A for instance, I have a Hegel, class A/B amp. I’ve tried three times asking the company how many watts are class A and never got an answer!  The third time I asked, I was told that because of their design, it all sounds like class A!

I actually sent an EMAIL to my amp manufacturer earlier today and they already replied back. They claim my Coda #8 V1 does 18 watts class A into 8 ohms and around 12 watts Class A into 4 ohms. This corresponds to what @swede58 said with his Pass amp. Thanks for everyone's help on understanding this.

@curiousjim - well their answer is completely BS.  Sounds like Class A.  I have to laugh at what manufacturers actually say to their customers.

Happy Listening.