VACUUM TUBE AMPLIFIERS LX-380 ,any comment?

never saw or heard it, just looked on their site

feature set looks great, until I got to this

Rated output: 20W + 20W (6Ω), 18W + 18W (8Ω), 14W + 14W (4Ω)

That demands very efficient speakers, which I am in favor of, but by experience/instinct I like having 30/35 wpc minimum.

Highly efficient speakers, often horns, need/have large efficient woofers to keep up with the horns, so large enclosures, exactly what I have used with 4 different tube amps over the years, 30/35/35/45 wpc.

so limited to rooms that can handle large speakers properly away from walls/corners. Now, trying to fill that space with 18 wpc at 8 ohms?

wpc usually increases i.e. 20 wpc 8 ohm/40 wpc 4 ohm, this design is only 14 wpc 4 ohm.

option: efficient smaller mains, and a pair of self powered subs, directional adjacent to mains for stereo bass.

I would want 2 phono inputs, both MM, let MC be boosted via SUT or separate MC Phono. Keep phono more versatile.

Remote volume? Remote Balance?

Thank you for your very clear answer, your explanation in my case would be to drive a Bowers 805 D3, another option that I am seeing is MC 275 from Mcintosh.

I do not like your idea of Bowers 805 D3, certainly not with the luxman amp.

bowers specs below: only 88db 1w 1m, that's low efficiency needing more power.

yes those speakers with McIntosh MC275
yes those speakers with Carver Crimson 275

but, 

 they will need a pair of powered subs, they are bass limited,

42Hz to 28kHz (+/-3dB from reference axis)

and, I don't like ports.

       

Description

2-way vented-box system    

Drive units
1x ø25mm (1 in) Diamond dome high-frequency    
1x ø165mm (6.5 in) Continuum™ cone bass midrange        

Frequency range
34Hz to 35kHz        

Frequency response (+/-3dB from reference axis)
42Hz to 28kHz            

Sensitivity (1m on axis at 2.83Vrms)
88dB

Harmonic distortion
2nd and 3rd harmonics (90dB, 1m on axis)    
<1 % 70Hz - 20kHz    
<0.6% 120Hz - 20kHz            

Nominal impedance (min)
8Ω (minimum 4.6Ω)        

Recommended amplifier power
50W - 120W into 8Ω on unclipped programme    

....................................

I would find full range non-ported speakers to use with a tube amp, efficiency 90db or above, then look for tube amp 35-45-75 wpc.

or, for smaller speakers, non-ported mains, still 90db efficiency, with less bass, combined with a pair of self-powered subs.

thank you very much again
It can also be an integrated like MA 8900 or Luxman L-509X, what do you think?