Speakers and Tube Amps

Mike, as Swampwalker suggests, you can ask. Or if you want to do some legwork (or keyboardwork), you can see whose amplifiers they have shown with at audio shows.

When I first became a SoundLab dealer, I was quite frustrated that the factory wouldn't tell me what amplifiers work well with their speakers. They gave me generic answers that were of no help. So I tried a different approach: "What manufacturers have you shown with at audio shows?" Well immediately their tongues loosened and soon I had a list of amplifier manufacturers to look at.

So, you might try asking that question if the more straightforward one doesn't work.

Duke

Duke said it better than I can. FWIW Wilson has shown with Audio Research a good deal in the past and ARC has Wilson speakers in house. So despite the dips in impedance, Wilson's are 'tube friendly'.

The Wilson Watt has long been an example of the phenomena that Duke presented above. The speaker had a reputation some years back for being bright- around 2KHz. There was a tweeter resonance at that frequency, which anyone with a transistor amp would tell you was uncontrolled. The tweeter did in fact have a resonance, but Wilson controlled it with a 'band reject' filter, tuned to 2KHz, which caused the speaker to have a 2 ohm impedance at that frequency. The rest of the speaker was about 8 ohms; transistor amps would dump power into that filter, and tube amps would not make any power due to the filter. As a result the speaker sounded great with good tube amps, bright with transistor amps.

Atmasphere
does the type of cross overs being implemented in the loudspeaker design play much of a part in whether or not a particular speaker is seen as Tube or SS friendly-er?

Such as 1st & 2nd order, vs. say 4th order types?

I would second the horn recommendation in general, and the Klipsch Cornwall recommendation in particular, unless you have a small room, then maybe something smaller in the Klipsch Heritage line. I have Cornwall II's that have 101dB efficiency. The very high efficiency is especially important if you want to experiment with SET amps. If you get speakers with this high efficiency, it almost won't matter what you drive them with, though, and the Cornwall's sound fantastic.

Audiokinesis, that was well put and great info. above. In the past I did exactly what you described and the manufacture said well this tube amp works great with our product etc.