Cube Audio Nenuphar Single Driver Speaker (10 inch) TQWT Enclosure

Cube Audio (Poland) designs single drivers and single driver speakers. 

Principals are Grzegorz Rulka and Marek Kostrzyński.

Link to the Cube Audio Nenuphar (with F10 Neo driver) speaker page:

Link to 6Moons review by Srajan Ebaen (August 2018):


Parameters (from Cube Audio):

Power: 40 W

Efficiency: 92 dB

Frequency response: 30Hz - 18kHz ( 6db)*

Dimensions: 30 x 50 x 105 cm

Weight: 40 Kg

* Frequency response may vary and depends on room size and accompanying electronic equipment.
They’re labeled as radiotron but that’s all I know. 
I'm impressed with the use of Tamura power and output transformers.  This builder was serious about pursuing very high quality sound. I bet this amplifier sounds beautiful driving your Nenuphars. 
@abd1 looks like RCA 45, and RCA 6sn7.  I have not heard RCA 45, yet, but my experience with RCA 6sn7 is that they are very dull sounding and not as musical as other 6sn7 out there.  I really like Brimar cv1988 6sn7 but they are pretty much unobtainium now a day.  Other NOS tubes I like is the Tungsol black glass, get the cheaper 6f8g with adapter, they sound the same as their 6sn7 counter parts.  I also like the new production tubes like the black treasure.  

I have the Brimar, Tungsol and JJ will report back when I get I get the chance to try them.  Alan mentioned it will take him 2 weeks to build.
I have an Alan Eaton 45 albeit with Omega Speakers. It's a wonderfully musical amp. Those transformers are magical. The SRPP stage is great as it has lots of low impedance "grunt" to drive triode finals. A very dynamic 1.5 watts! I like the RCA 6sn7. They are certainly more chill sounding than VT-231. Hitachi 6sn7gtb are really good too. I use shoulder, globes, and EML - I like them all. I can see why a lot of people would gravitate to the EML as it sounds like a more powerful amp. Down the road consider swapping the coupling caps, volume pots, and removing the little .1 caps coming off the RCA. They aren't necessary unless you have noisy sources. It sounds very nice in stock form but the mods bump the fidelity up a notch or two.