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: 

https://www.cubeaudio.eu/cube-audio-nenuphar

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

https://6moons.com/audioreview_articles/cubeaudio2/

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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.
david_ten
@debjit_g If you are still looking at amps, and a 2A3 is still an option...

My Found-Music 2A3 drives the Nenuphars with ease. I top out at 90dB averages when I choose to crank the music. We have had it up over 100dB averages for a couple of audio buddies who prefer their music really loud. Above 90dB levels, my untreated room asserts itself as an unwelcome actor.

[Note: by average, I mean the average over the recording (including peaks)]

My usual (and normal) listening levels are in the low 70dB range with averaged peaks in mid to high 80 (spikes into the 90s); recording dependant, of course.

Room is 19 ft by 26 ft.

I am hoping that the 2A3 can power the Cube’s to a comfortable listening level when the listening position is 8-9ft from the speaker.

Not all 2A3s are created equal. I encourage you to reach out to @charles1dad and others qualified to address build quality.
General comment for those not active in this thread: the designers of Cube Audio's Nenuphar (and variants) have routinely shown their work paired with low watt (45 and 2A3) SET amplifiers.

Peter Breuninger, of AVShowrooms, fell under the spell of the Nenuphar Minis driven by the Tektron 45/50 SET amp. Just another recent example of the exceptional synergy of the Nenuphar(s) with low watt amps.
Speaking of the resistor solution, Stephen, could you elucidate more? Were they across the terminals? Were they at the amp or the speaker? Are they in series or parallel?

TIA,
Robert
Robert,

The resistors were connected between the positive output of the amp and positive speaker cable connector.  So I wound one end around the WBT positive terminal of the VR and the other end I wound around the banana plug of the speaker cable.  When I asked Vinnie if he suggested soldering the connection to the banana plug, which is probably not a good idea considering possible damage or visual marring of the banana plug he replied:
"It might be a good idea to make that resistor connection better.  Maybe a male banana on one end (to the L2) and female banana jack on the other end (to your speaker cable)."

As to your question about whether the resistors are in series or parallel, I am not technical enough to answer, although my guess is since there is only one resister per channel they are definitely not in series.

BTW I checked out your room.  Beautiful space and great set up.  Despite the height of your ceiling, I think you'll be surprised how the Nenuphars will fill the space.  When I went to this catty corner speaker set up I was shocked how much more height there was to the soundstage. Listening to Cohen Live In London my room took on the dimensions of that enormous hall where the concert took place.  I thought this was strange considering the ceiling height (14') hadn't changed from my previous set up with speakers 3' out from the long wall.  
@stephendunn Thanks for the additional information regarding resistor setup, much appreciated.

That would actually be a series connection. In parallel circuits, electricity is flowing through two independent circuits. If either is cut, the other circuit will be still be conducting electricity (think modern Christmas lights where breaks in the circuit, i.e. a burned out bulb, don't cut out the whole stand). Alternatively, in a series circuit, each component is an integral part of the circuit and if it breaks, no electricity flows (i.e, old Christmas light strands where every bulb needed to be tested to find the fault).

In this case your amp is producing electricity and the positive & negative wires complete that circuit and allow it to flow through the speaker. If the resistor were connected in parallel to that circuit, it would be connected to both the positive and negative terminals of the amp (or speaker). Cut one leg of the resistor and the full speaker circuit is still connected to both terminals, electricity flows, and the music continues.  Instead, you've got it connected in series with the speaker circuit. Cut one leg of the resistor and it breaks the circuit and there's no connection/electricity/music.