Gain calculations, two different amps

I noticed an interesting topic in Audio Asylum concerning bi-amping and input sensitivity. I copy here part of the answer, full text here. Topic issue is bi-amping with Art Audio Carissa and Cary Audio SLM200, input sensitivity 0.6V and 0.7V, respectively.

"You want the gains of the two amps to be the same into the same load. To convert sensitivity to gain, you have to calculate the output voltage into the load at the rated power of the amp.

P=I*E and I=E/R so P=E^2/R.

Solving for E gives you E=Sqrt(P*R). Gain equals 20*log(Eout/Ein). For the Carissa rated at 16 watts (I assume into 8 ohms) with a sensitivity of 0.6 the gain can be calculated as follows.

E= sqrt(16*8)=11.3v and the gain is 20*log(11.3/0.6)=25.5.

Similarly for the Cary rated a 130 watts into 8 ohms

V=sqrt(130*8)=32.2 so the gain is 20*log(32.2/0.7)=33.2. Thus your amps have a 8db difference in gain which is not so good. "