Tube amps and speaker ohms


In your opinion , do push pull amps work better with 8 ohms or 4 ohms. .I am under the impression the lower the ohms, the more power is demanded from the amp....Another question, are there low powered SET amps ,and high power SET amps?
I'm looking at a 40 watt 845 tube amp for my 8 ohm, 89 db speaker.. just cked the Thor has a 86 db W18 midwoofers(2 per cabinet) and a 88 db tweeter. Will an 845 amp rated 40 watts be able to drive the 86/88 db speaker? With authority, bass, mids, highs, in dynamic sound stage? Synergy? Or poor match?
bartokfan
Grant, my KT77 comments are based solely on listening to the JJ variant. I'm not sure how the Osram (didn't know they made KT77) and Mullards would sound.

In my Jadis DA60 and Dennis' (Badboss429) Quicksilver, a bunch of us (including Mechans) compared the JJ E34L blue glass, JJ KT77, vintage 1960s Mullard EL34 XF1 (EL34 Holy Grail), and JJ KT88 blue glass. The KT88 came in last. The rest of the tubes had a variety of opinions. Overall, things seemed to split between the Mullard and JJ E34L, but many of us couldn't get past the powerful, intoxicating lows of the JJ KT77.

From what I heard, the first batch of KT77 had issues with the tube pins. The octet I bought in January/February 20076 had this issue corrected. Didn't have any fail, either, but it's a complaint many have put forth with JJ power tubes in general. I have an octet of E34L Blue Glass, and one day while measuring them about three weeks ago, I found one was as dead as a doornail. That came as kind of a shock.
Hi Divad. I tried to post before, but I cannot see the post so here goes again.

First off, I am a very pro tube guy, but I would advise you very strongly against going tubes with your speakers. Your speakers are not suited for a tube amplifier.

You may get them to “work” by using a big tube amp, but it is never going to be a good match and neither your speakers nor the tube amp will be sounding their best. You’ll be much better off with a solid state amp.

If you really want to try tubes, you need to ditch the B&Ws.

Regards
Paul
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Hi Paul. Thanks for your comments. I really do want to switch to tubes and will move away from B&W's. Probably shortly after receiving my first all tube amp!

Sticking with floorstanders that have a healthy bass output and are not bright or overly forward sounding, can you suggest any manufacturers/models I should potentially be shortlisting?

Cheers
David (have to invert my name and use divad as david is always taken as a username!!)
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