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

Thank you David for both the warm introduction and your patient guidance in selecting and sourcing the Nenuphar V2s.

It has taken quite a bit longer than I originally planned to get the all new system in place. First was Axpona 2022 delaying the shipment of the new Nenuphars. Best laid plans and all that…

Then, my first choice for amplification, a NAT Audio Single HPS integrated amp failed to operate properly during testing at the distributor and is currently stranded with the hood up awaiting parts. Fortunately @rwpollock posted here a few days ago that he was parting with his First Watt SIT-2 and I snatched it up (thanks Bob!). Very fortuitous, except that I have no appropriate external preamp solution at present (since the NAT Audio integrated needed none), so I am temporarily limited to driving the SIT-2 directly from the single ended outputs of the Meitner MA3, also new to me, using its (reportedly excellent) VControl digital volume control.

The SIT-2 arrived this afternoon and I am now listening to the rig for the first time as I write. First thing that strikes me is the very satisfying bass performance from the Nenuphars. Next is the enormous soundstage and the sense of true depth and proportionate spatial relationship between instruments and performers.

Not all is peachy yet of course. The V2 drivers, being brand spanking new, are still way tight, lack top end airiness/open-ness and overall dynamics, especially in the treble region, sounding overly polite thus lacking essential sparkle. I am expecting some improvement in these areas as the drivers loosen up and everything settles in, but I am thinking that a true active preamp addition to drive the SIT-2 is already proving mandatory.

I have my old Ayre K-1xe preamp in storage but really wish to employ tubes this time around. Suggestions anyone?

Pass/Cube Audio room was deemed “Best of Show” by this guy. FF to 10 minutes in…

Just popped up on YT

I can’t see it either…

Hi Robert ,

Just sent you a PM

David

@rwpollock Gotcha. Later last night I found that the sound is considerably better with the polarity reversed at the SIT-2s output terminals. Nelson touches on this in the manual but I found the wording ambiguous, perhaps encouraging experimentation.

@charles1dad Re: why the drastic change in direction from my Thiel rig, great question. Part of it is the old “been there done that” idiom. Having spent over 20 years with the CS5i’s (which initially were challenging to please), I feel as though I reached somewhat of a pinnacle with that system, at least within my financial means. Newer high-power SS gear has become very pricey. Second, during 20+ years of continuous improvement with the Thiel system, I never could get the speakers to “wake up” at low (or even moderately conservative) volume. On balance, they did achieve a pretty awesome result IMO when listening at higher volume. Lastly, I have always longed to experience the wetter and more harmonically natural tube sound. The CS5i’s are 87 db efficient and dip to nearly 2 ohms in the lower frequencies. Amp killer. I never felt tube amplifiers were viable with them (although I remain convinced that they would benefit greatly from what good tubes bring sonically). I must say I never experienced reliability issues with robust SS amplifiers (Krell and early-gen Classe Audio). As an aside, I clearly recall listening (alone) in just my underwear when I had the Class A-biased Krell FPB 600c in the rig due to the incredible heat that amp generates.

Hopefully the NAT Audio integrated will soon be healthy to begin my tube journey. In the meantime, the SIT-2, being a known entity with the Nenuphars, should provide me with a baseline to ground my exploration into tubes driving the V2’s.

@johnk “After all, it's a system we listen to and synergy is the goal.” 
 

Very true.

@charles1dad i would love to know too lol

Stumbled on this mini-review of the Nenuphar and I don’t believe it has been posted here yet. I find it to be the best description of their sound character I have seen:

https://eastendhifi.com/cube-audio-nenuphar-speakers-a-desert-island-speaker/

Hi Charles, @gavin1977 statement referred specifically to the F10 Select driver which is used in the Jazzon. The Nenuphar uses the F10 Neo driver, which has a quite different magnet assembly.

Could be that he intended the comment toward both drivers. Having owned Nenuphars for over a year and experienced the break-in and associated system-optimization learning curve, I can see where someone new to these crossover-less full-range speakers could form this impression IF the drivers are not fully broken-in OR IF the accompanying system is not sorted OR IF the toe-in is incorrect.

These speakers provide little cushion for mismatched components (especially regarding amplifiers), suboptimal setup, etc, and they produce tremendous energy across the frequency spectrum (no crossover to dumb down the dynamics of the incoming signal through parasitic loss), so ancillary components with a hot upper midrange can be problematic. However, getting these things sorted delivers a sound that is so fundamentally right that, for me, it is nigh impossible to imagine returning to standard multi-driver “crossover-ed” speakers.

@gavin1977 that frequency response curve for the Nenuphars is for the V1 version. Changes in cone configuration in the V2 version largely addressed what you describe (has a fuller midbass and less upper midrange rise). Yet, IME the V2 is still sensitive to toe-in much as the multiple lines on the V1 graph indicate.

Haven’t heard the Jazzon in person, but, as you say, its graph looks to support your experience, at least at whatever toe-in was used for that single line. It would be informative to see the graph at different toe-ins for the Jazzon. My bet, based on working with the Nenuphars, is that room placement/room treatment/toe-in optimization should go a long way toward improving the peaks and valleys shown with the Jazzon.

@david_ten Welcome back David! You were missed.

@abd1 It’s good to hear that your Nenuphar Mini’s have “come on voice”. I too experienced a VERY extended break-in period with my Nenuphar V2’s and sometimes doubted my choice during that time, but once the Nenuphars settled in I could not be happier.

Re: the Atma-Sphere GaNFET as a potential “warmer months” amplifier choice with your Nenuphar Minis; based on the published output impedance spec of ~0.010 ohms, their damping factor into an 8 ohm load would be very high, making them a poor compatibility choice with your Minis. As @whitestix ​​​​@charles1dad state above, amplifier choice is very critical to achieving balanced tonality with the Cube full-range drivers, so choose an amplifier with higher output impedance (think ~ 0.8 ohms optimally) and thus a low damping factor (think 10 or so optimally). The Enleum 23R is said by many to work very well.

@larryi Cube Audio primarily pairs their speakers with Tekron 2a3 SET tube amps for shows and demos. Sometimes the US Distributor uses First Watt SIT amplifiers at shows. Very unique solid state amplifiers designed by Nelson Pass that behave electrically and sonically like SET tube amps. The SIT-1 and SIT-2 have an output impedance of 4 ohms and a damping factor of 2 while the SIT-3 has a less ideal .25 ohm/30 DF rating. This review explains in all thoroughly: https://www.6moons.com/audioreviews2/cubeaudio2/6.html