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.

@charles1dad ditto. I was under the same impression. Inquiring minds want to know what backs up that statement.


In all candor I don’t believe there is a backing up statement. Certainly due to personal taste preference one might prefer a 45 /2A3, nothing unusual there. By the same token other listeners may prefer the 300b. Normal variance depending on numerous audio system factors.


Here's some food for thought:  I think this a question for Cube Audio with respect to the V1 and they will see it as a mute point.  Why did Cube Audio have a list of compatible amplifiers when they offered the V1s?  You don't see a recommended list for the V2s. Why did the Mono & Stereo Review state: "For tube amplifiers, Cube Audio recommends such designs based on 2A3, Px4, 45 tubes" and not 2A3, Px4, 45, and 300B tubes.  Have you ever seen Cube or Refined Audio specifically demo with 300B based amps? I remember addressing this exact question at some point in my search.  

Seems like considerable conjecture in all honesty. I can’t think of any logical reason why a 300b amplifier would not be a fine choice. Certainly no technical reason. I’d love a comment directly from Cube Audio on this topic. I would be very surprised if they said there is some reason to avoid the 300b. Again, to me it appears to be a terrific pairing.


@mikeg Mike, in addition to simple preference, perhaps the industry association for shows, etc. may have been a factor. Tektron Audio and Cube Audio in Europe. Refined Audio being a Pass Labs dealer factors for the US shows.

If Grzegorz has reasons for not recommending a 300B or for putting it lower on Cube’s recommended list...I’d love to know the reasons.

Here is a screenshot of the recommended amplifiers (I believe this was the list when the V1 was in existence) from Cube Audio.

A number of 300B amps are in the "Amplifiers that work well with Cube Audio speakers" list.

[Note: I was not able to re-format the font size, etc. below] In other words, I'm not shouting!!! 😊


Amplifiers that are working very well with all Cube Audio speakers

Up to 4’000 Euro

  • First Watt SIT-3

  • Feliks 300b Arioso

  • Fezz Audio Lybra 300B

  • Fezz Audio Mira Ceti 300B

  • Music book 250 Power

  • Naim Audio XS2

  • Naim Audio Uniti Atom

  • Sun Audio 2A3

  • Quad Artera Pre + Power

  • Tsakiridis AEOLOS PLUS EL34

  • Tsakiridis Hermes EL84

  • Tsakiridis ORPHEUS 211

4’000 - 10’000 Euro

  • Aesthetix Mimas

  • Bakoon amp13r

  • FANTINI 2 GM-70

  • First Watt SIT-1

  • Manley Stingray II

  • Quad II Classic

  • Sun Audio 300B

  • Tektron TK211SI REF

  • Tektron TK2A3/300BPSE-I-REF

  • Tektron TK300BS-I-ECY

  • Verdier 300B

  • Viva Solistino integrated

Over 10’000 Euro

  • Absolare Intergrated SE

  • Aesthetix Calypso Eclipse + Quad II80 Monos

  • Aesthetix Janus Eclipse Pre + Line Magnetic 503 Monos

  • Aries Cerat GENUS integrated

  • Aries Cerat Incito-S + Concero 25Aries Cerat GENUS integrated

  • EAR 509

  • Grandinote Genesi + Demone

  • Grandinote Shinai integrated

  • Shindo Cortese 300B

  • Wyred4Sound Pre + Quad II 80 Monos

  • Tektron TK211MPSE REF Mono Pair