Question about set amps and low sensitivity spkrs


Hi, In about 3 weeks I will take ownership of an 18wpc SET integrated. I currently run an Arcam SS amp with B&W 602 S2 speakers and I'm still undecided about new speakers (more sensitive, tube friendly) to mate with my new amp. My question is, can I run my current 90db sensitive B&W speakers with the SET integrated without doing damage, or shortening the life of my new tubes? I'd hate to have the amp sitting in a box waiting for me to decide on new speakers :) I frequently see that B&W speakers don't mate well with tubes...why is this?
thanks
Michael
mbleming
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Tvad, I thought that was they way SS usually works, but not tubes (but I'm no expert).I know when I owned the RM10 Roger Modjeski said I would loose power if I used the 4 ohm tap versus the 8 ohm, but there were advantages in terms of dampening and distortion. By the way Mbleming, what amp are you using?
FWIW most tube amps put out the same wattage at 4 & 8 ohms. It neither doubles nor halves. 18w at 8 ohms is going to be 18w at 4 ohms.
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Thanks again guys, very much appreciated. As far as speakers go, I have been giving serious thought to the Devore Gibbons, but I'm still not sure. Thanks again!