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?
+++ the only way to achieve constant voltage drive with a changing load impedance is by having very low amplifier impedance+++

This statement is not totally accurate.

Constant voltage can be achieved when the amplifier has a relatively low output impedance compared to the speaker impedance AND when the speaker has a benign impedance curve across the frequency range.

In the same manner that some carts require very careful matching with a specific tonearm to perform their best, vacuum tube amplifiers require the same careful attention in matching them to the appropriate speakers.

But then I am not telling you something you do not know already Raul? ;-)

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>>They seem to be disgusted with my cheering the Seas labs creation<<

Not really. It's your inability to grasp the technology and related issues that's disgusting. Your cheering is simply an extension of that.
Tvad, I should have posted about driver in house design vs mass market poly cones, on the topic Harbeth vs Tyler. i goofed up, and mixed comments. Back to topic of tube amps transformers and the resistance from the motor and crossovers in speaker designs. A low volt tube amp, or lets say one that has trouble maintaining proper volt current when demand gets high, will not bring out the FULL potential of certain demanding speakers. Go to Jadis' web page, look inside the DA88. Designed to meet any demand from any speaker. Quality doesn't come cheap. Although certain chinese labs are comming along quite nicely. We can talk theoy here all we want. We are more interested in which labs are actually producing a tube amp to meet demanding power hungry speakers. I'll leave the tech stuff to their engineers. I am only interested in the end result. Does the setup produce a high fidelity musical image? Thats all, nothing more.
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