The first watts

After transition from class A (both transistors conducting) to class B (only one transistor conducting at given moment) it is already linear and class name doesn't make any difference. Actually, increasing bias point to keep it longer in class A would increase distortion (overbias) since it increases area of double gain (gm doubling) caused by the fact two transistors operate instead of one.

I used to have a full class a amp that one could cook a steak on. I didn't feel the marginal benefits were worth the price, weight, and excessive heat.

for the record I'm using Thiel CS 2.4's

11-21-14: Jmcgrogan2
Power works on a logarithmic scale, meaning that 100 wpc will sound twice as loud as 10 wpc (+3dB).

Whoops, that should read +10 dB. 10 times the power gives you twice the volume, or +10 dB. Sorry about that confusion.

So 10 watts is twice as loud as 1 watt. So your speakers, rated at 87 dB @ 1 watt, should be able to get up to 97 dB in an amp that switches over to Class AB at 10 wpc. Probably most of your listening would be in Class A, unless you are a headbanger.

So your speakers, rated at 87 dB @ 1 watt, should be able to get up to 97 dB in an amp that switches over to Class AB at 10 wpc. Probably most of your listening would be in Class A, unless you are a headbanger.

Sorry, that's not exactly right. The speakers are rated at 87dB/2.83V/m and since the speaker is 4 ohm, that will be 2 watts. Then there is a gain for 2 speakers, and a loss for listening distance greater than 1 meter. So a rough estimate for a distance of 2.5 meters using 10 watts would be ~92dB. Also, even if the average SPL is 75dB, some music can have dynamic peaks of 95dB and higher. If you really want to know, get a sound level meter, and measure the peak SPL when you listen.