Question about tube friendly speakers...

you should understand that there are several different issues on selecting a tube-friendly speaker:
for me it means that the tube can drive this speaker with no transformer on the output i.e. OTL.
such speaker should have relatively high impedance 10...60Ohm like Coincident to get the tube's best performance.
if a tube or even ss amp has an output transformer than you should select a "transformer-friendly" speaker that basically has relatively flat curve of impedance.
there are also wide-band transformers that have relatively flat and stable responce from 2 upto 16 Ohms(actually used in Macs, VTLs and ARC). i believe that performance of such transformers far superior and safer than any direct-coupling whether tube or ss.
as to efficiency with tube amps you can drive your low efficiency speakers with under-powered tube amp since tube clipping is not destructive to the speaker if it satisfies your room and volume levels.
specifications for the nominal load isn't a factor and for real matching to the amp rather than having impedance curves plotted in front of you. many speakers have a nominal impedance and even minimum impedance specified without specifying the maximum that can also present a tough load and certainly losses of the amp's output power.

Marakanetz is absolutely correct IMO. I ditto everything he says. I have done a ton of research lately about this (qualitative as well as quantitative) since deciding to get a tube setup and your question requires more infomation about the amp to answer correctly. Arthur

Audiogoners, hypothetically, based on specs alone, are the specs I provided on the speakers enough to make a theory-based choice on speakers? If not, what more is needed? Say this info will be used to build a short list of speakers to be auditioned at a later time(it would take a lifetime to audtion EVERYTHING).

Next, what kind of info is then required to know about the amp you will be using if wattage and ohm tap is not enough?

I believe that in your case you should select the speaker with no less than 6 Ohm minimal impedace(usually rated for lowest freequencies)

Audio Note Type J speakers operate between 6 and 8 ohms is what I've been advised by Audio Note. They work great with transformer tube amps. I use a P2SE with 18 watts and the SPL is way more than I can handle; plenty of power.