Tony L
Administrator
What makes a great amplifier is low distortion.
Amplifier distortion has been orders of magnitude below typical loudspeaker distortion for a lot longer than I’ve been alive. It is just not the bottleneck. A 1948 Leak TL12.1 gets its name from being able to deliver its (in most cases perfectly adequate) 12 Watts at less that 0.1% THD. Find me any loudspeaker regardless of price that can match that! Specs are only of use these days if you are trying to match speakers that are real outliers, and then you tend to be looking at power output, stability into specific loads, damping factor etc. Distortion was at inaudible levels 70+ years ago!
Basically amplifier design is a mature technology. The only real “gains” of recent decades are in cost-cutting, power efficiency, and ease of mass manufacturing. This to the point most sold in the consumer realm are now throw-away landfill tat that will be lucky to last a decade.