Anyone experienced the Luxman MQ-300 or/and The Air Tight ATM-300R?

The MQ-300 is one sweet performer.

:)

Both of these 300b SET amplifiers are very highly regarded and receive universal praise. It does seem though that the Luxman MQ 300 gets exceptionally high compliments and admiration. It is a top tier effort from Luxman who seem to have gone all out to make it a state of the art SET. People who have actually heard it say it’s outstanding. I have no reason to question this and I suspect it is truly special. Good luck to you in your search.

Is the Devore Super 9 sensitive and efficient enough for these 8 watt SET amplifiers to fully demostrate their considerable capabilities?
Charles 

Charles is on the right path and the answer is no. 

Keithr,
I looked up the speaker’s specifications and sensitivity is 91db and impedance load is 8 ohms with a minimum of 6 ohms. So sensitivity is really  on the fringe  borderline. The speaker load is a relatively easy one. Room is 14 x 16ft .

If the OP is really interested in using a SET amplifier I’d suggest considering a good quality 845 ,805 or 211 output tube based amplifier. In the Dagogo review by the "Beatnik" he used four amplifiers and said that the best sound was achieved with his First Watt S.I.T. 3 which is an 18 watt solid state amplifier.

The above mentioned/recommended tubes will provide typically 20 to 30 watts (845 And 211). The 805 tube will yield 40 to 45 watts as an SET. Of course with these SETs the quality of the output transformer and power supply are major factors to recognize.

Back to the OP’s question, I believe he’d need to hear the two esteemed 300b SETs with his speaker (Or one with very similar specifications ) to determine if the pairing is feasible. I'm a 300b aficianodo but in this circumstance the bigger higher power  transmission output tubes may be more suitable. 
Charles

Thanks ! I think it would probably be worth the try as I am using a MQ 88 U se right now and I rarely push my pre pass 9 o’clock .