Sensitivity 86 v 90

Thanks for the explanations!

My integrated amp (Rogers EHF 200 Mk 2) has 40 db of gain.  The volume control is turned up much less with signal from the dac, than while using the phono preamp, which I presume  means the dac has higher output; but (as I understand it) the gain from the phono preamp can be increased by switching the driver 12AU7 tubes for 12AX7's, if necessary.  Which, maybe I should do anyway, as @Soix and @tomcarr imply.

To answer the questions, I have been using PMC Fb1i Signature speakers. 2-way, 90 db sensitivity.  Went ahead and bought PMC Twenty5.26, 3-way at 86 db sensitivity.  Based on the cogent responses here, I am optimistic this will work out ok. 
phono preamp is a Rogers PA-2.  Cartridge is Lyra Kleos, .5 mv output version. I agree with the suggestions that the phono output is probably too low.   I can increase it by changing the driver tubes from 12au7 to 12av7 or 12ax7; I will try that. 

thanks again for all the responses, this had been interesting and very informative.  I will have to read it all again several times.

I went ahead and bought the less sensitive speakers (PMC 25.26 @ 87db, replacing PMC FB1i Signature @ 90db sensitivity) and if anything, they seem to produce more volume at a given setting.  I can only speculate as to why, but now I’m certain that speaker sensitivity has very little predictive value, given my level of (mis)understanding of these things. I suppose there are just too many variables involved.

@ atmasphere

Roger says the circuit is designed to use any 12a_7 in that spot.  I don’t know how he does it.  Apparently the 12au7 is the quietist (and lowest gain) and perhaps, the best sounding, but 12au7, 12ax7, and 12at7 all work fine in that spot.