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Hi all, I swopped my Rotel 200W power amp for a Cambridge Audio 200W power amp and at the same relative volume on the preamp, the volume was considerably louder on the Cambridge.

From this, I deduced that the 200W is a lot more powerful than the 200W on the Rotel, which to me doesn't make any sense. So now my questions :

Can the same wattage amp but with a different gain really have such a large impact on loudness?

But if the gain results in a much louder sound from the same relative position along the volume pot (according to amp gain calculation formula from https://www.kynix.com/Blog/Introduction-to-Amplifier-Gain-in-dB-and-Calculation.html), and both amps have similar power output, then wouldn't the amp with higher gain reach full output sooner than the other?

I guess I'm just trying to understand what's going on here. I always assumed that two power amps of equal power output would have equal loudness as the volume was turned up, but I guess my assumptions are inaccurate or incomplete.

Thanks for your time. Best regards

You have just experimentally verified that power and gain are two different things!

Can the same wattage amp but with a different gain really have such a large impact on loudness?

YES.

wouldn't the amp with higher gain reach full output sooner than the other?

YES.

Do you have the gain specifications for both amplifiers? With that, you could devise a test method to produce the same power output from each amplifier and compare loudness.