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

Sounds great David. Would love to hear them, especially with the Nenuphars. As Charles said, I'm sure it'll be an amazing pairing.

For Cal; and others who may be interested...

Here are some of the general differences between the custom 2A3 build by Scott and his former, my current, Found-Music 2A3 amps:


* 4 chassis design, heavier construction vs. a 2 chassis design

* DC regulated filament/heaters vs. AC heated

* driver circuitry and theory is different, now actively loaded

* driver tubes are mirrored vs. a single tube

* active regulation in PS

* amps will be prioritized for signal purity and performance...amps I have were designed to prioritize output power

* high purity silver cabling throughout vs. copper cabling

* Different and ’superior’ output transformers


I’ll update as the build progresses.

Given that the Nenuphar is precisely designed to optimize the bass response utilizing a bottom front cabinet port and interaction with the floor, has anyone had to contend with any degradation caused by think cut-pile carpet?

david_ten Congrats on your new amps.  Can't wait to hear your report.

BTW I ended up with the Sigma NR V2 power cable instead of the Omega.  When attached to the VR L2i-SE it had 85% of the benefits of the Omega at 50% of the price.  Still truly remarkable. 

Next up, I'm auditioning some Shunyata Alpha NR V2 speaker cables. 

David,
That link you posted brought back pleasant memories . Mike Lavigne bringing the Found Music 2A3 SET mono blocks to my and other audiophiles attention. State of the art design and built quality to implement by all accounts an exquisite sounding amplifier.

Now this will be taken to the next level as an all out assault 4 chassis amplifier with even better output transformers, separate power supply chassis  per channel. The Nenuphars will extract every bit of performance these amplifiers have to offer. Very exciting times ahead. This will be fun!
Charles

Great, thanks. I've been following Mike's speaker journey recently, so this is great context.

Thank you, Charles.

@cal3713   Thanks! I'll put together a proper summary of differences, etc. and get back to you.

Some high level differences: 2 chassis vs. 4 chassis. Copper vs. Silver wiring. Different output transformers. AC heating vs. DC heating. Etc.

Here is some information on my current 2A3 amp, courtesy of What's Best Forum:

https://www.whatsbestforum.com/threads/found-music-2a3-amplifier.4279/

Sounds awesome David. Congrats!

Can you remind me what your current 2a3 model is and how the new build differs?

Congratulations David,
I know how much thought,  research and time you've devoted to this search and decision. In my humble opinion the end result for you will be extraordinary sound quality and music reproduction in your home.
Charles 

For the past nine months, I’ve been thinking through and processing possible amplifier pairings for the Nenuphars. Came close to acquiring: Audion Golden Dreams, the New Audio Frontiers 211 SET, Ayon Crossfire/Vulcan EVOs, EM/IA 50/300b, etc.

I made a choice of designer/builder a couple of weeks ago and committed to the specific build today. After one heck of a journey across brands, a variety of power output tubes, SET vs. Parallel vs. Push-Pull builds, etc., etc. I ended up very close to home, in amplifier speak.

I’m moving forward with a custom 2A3 build by Scott Sheaffer (Found-Music). This build will ’make less power in the zone’ than my current Found-Music 2A3s (2 to 3 watts vs. 3.5 to 4 watts).

Second finalist was the Thomas Mayer 300B multi-chassis build.

The amps should be in system by February / March.

A number of members helped with this. THANKS to all. You know who you are!!!

Bring out all the superlatives in the audiophile handbook (including where the bottom part of your face hits the floor) and add in something uncanny that had to do with speed and pace that focused my interest with a life like quality I’d never heard before.

@stephendunn  Congratulations on achieving what you are with your system, and thanks for sharing your findings and results with the Omega pc feeding your VR integrated.

@stephendunn, I agree with the newer Shunyata V2 being excellent. I am using Alpha NR v2 couple of months back on all components, except one. The Omega is far from reach at this point.

The Z10 works fine with my Nens. However, I do prefer the SIT-3 combo; it has more life and dynamics.

Thanks @rwpollock yes, the SIT-3 sounds wonderful. I was trying to see if I can simplify the setup with an integrated. What preamp do you use with the SIT-3 ?

@stephendunn Thanks for the reply. I'm like you where I've felt cables make a difference but also agree with the diminishing returns. Interesting to hear your experience, but for my wallet's sake I wish it weren't true.

"Did anyone try LTA Z10 with the Cubes? Anyone have compared the Z10 to a SIT-3?"

The Z10 works fine with my Nens. However, I do prefer the SIT-3 combo; it has more life and dynamics.

abd1...The Shunyata Omega replaced an Audience AU24 power chord, a David and Goliath match up.  This all came about because my audiophile friend insisted my old Audience cable wasn't good enough  for the VR.  I insisted that there was technology in the VR that made the power cord less important.  But I will say when my friend replaced another Audience AU24 cable with another very high end Shunyata pc (I think it was a Sigma NR V2) on my Totaldac, we could clearly hear improvements by degree but not the quantum leap the Omega gave us on the VR.

I have been a cable believer up to a point, thinking they were the classic example of diminishing returns in hi end audio.  But sometimes $7.5 grand really buys you that much of "better", especially if you're replacing an older technology.  I would have to sell another chunk of my Blue Note collection to afford it, so the jury's still out.

How did my old cable sound when I put it back in?  I don't know, I told my buddy I needed another week with the Omega to make sure I wasn't hearing things. (<:  

@stephendunn... I'm a cable believer however I've noticed the least difference with power cables. I am using a PS Audio P5 regenerator so I think they might have less an impact in my system since the power is regenerated. I love the P5 and did notice a big difference once I put it in my system. Anyway, I'm wondering what cable you replaced and what happened when you put your original cable back in? Did you notice a drop off in performance?

Well guys, I heard the Boenicke W13 and it wasn’t my cup of tea. I’m now looking to hear the Nenuphar and Fyne Audio - anyone hear both? I heard the big Tannoy Westminster recently which stoked my interest in the latter.

Hi Stephen,
Thanks as always for providing your listening impressions and observations.  I've been involved in enough cable comparisons over the years and know without question the positive impact high quality cables can impart in an audio system. 

I acknowledge there are those who would write off what you've heard and refuse to believe that cables/conditioners  are capable of providing this degree of sonic impact. That's their problem, not yours. I have no doubt that your system is sounding simply marvelous. You continue to discover how exceptional the Nenuphars truly are.
Charles 

At the risk of straying too far afield from the subject of this thread-- although really isn’t the subject the Nenuphar speakers and how to optimize them?--I want to report on an optimizer that’s a little further down the chain of the typical pairing of amps and/or pre amps. Just to remind folks I drive my N’s with the Vinnie Rossi L2i-SE (which bested by a surprising margin the LTA Ultralinear and First Watt SIT-3 and SIT-1 amps) and remain impressed if not overwhelmed by the synergy. (I see some folks here considering pre and amp combo’s that are about the price of the VR and would just say to put it on your radar.) In fact I was in that happy state of "it can’t get better than this" (a state where you should drop all your audiophile acquaintances and vendor relationships if you want to preserve it), when a friend brought over a power cable he said I had to hear. It was a Shunyata Omega QR 15 amp power cord as thick as a summer sausage. And it retails for $7.5K! This thing which is both a power conditioner and cable incorporating a bunch of technologies I thoroughly don’t understand, immediately raised the optimization bar of the Nenuphar’s by--I don’t know how to put it, a component, a mile, by more than anything except adding the VR? Even then I’m not sure, it was like adding another VR, just made everything BETTER BY A BUNCH. Bring out all the superlatives in the audiophile handbook (including where the bottom part of your face hits the floor) and add in something uncanny that had to do with speed and pace that focused my interest with a life like quality I’d never heard before. How good are the Nenuphar speakers? So good that changing that 6 feet of wire between your wall outlet and your amp could make them sound even bigger, more alive and life-like than you had heretofore thought possible. So far the Nenuphars have followed my dream and my pocket book as far as the two might take them.

Bon, thanks!  Cool. Say Hi to Jon from me. Looking forward to hearing your take on the Magus and Nenuphar Mini speakers. Your amps will be a nice pairing!

David I will start on Magus then the Mini floor standing.Yes I will let you know.Happy Thanksgiving belated and your family, my friend.

@jayctoy  Bon, share your impressions once you audition. Which models?

I just spoke to Jon very very nice person to talk to, Iam interested to audition 2 of his Speaker, maybe next week , since we are both busy at this time.I live maybe 45 minutes from Him.

Larry,
The damping factor and amplifier output impedance considerations were discussed in ample detail in the original Nenuphar review in 6 Moons several years ago. The driver designer and builder explains why this approach was chosen. Probably explained on their website as well. 
Charles 

Thanks David, will do.

@doni  Don, if you haven't done so, I suggest reaching out to Jon Ver Halen, the US importer for Cube Audio. He may be able to connect you with a client in your area should the client be willing, given the current situation.

Refined Audio contact link:

https://refinedaudio.com/pages/contact

Why is a low damping factor (high output impedance) desirable for these speakers?  Is the frequency response  change from the high output impedance and the impedance curve of the speaker a favorable interaction?

As a fan of low output tube amps, many of which have typically high output impedance (low damping factor), I generally don't find low damping factor to be a big deal, but, I never thought of it as a positive attribute.  

Did anyone try LTA Z10 with the Cubes ? I hope it has enough to power the Nenuphars. The spec doesn't list much details but folks at LTA said they use low -ive feedback and low DF. 
Anyone have compared the Z10 to a SIT-3 ?

@david_ten The speakers are supposed to arrive early-mid December. At least to the distributor. So I'm hoping to have them mid-late December. I'm very excited. So far I'm using the amp with my 85db standmounts and it has zero issues driving them. It's a push pull 300b creating 26wpc/8ohm. It does help that I'm using a pair of REL T5i's for the bass, but this amp is far from wimpy. I was lucky that the unit I purchased came with some nice tubes already. Vocals are so lifelike with this amp. Midrange is gorgeous as well. Its pretty dead quiet and effortless. My wife said this combo I'm using sounds so good why do I need new speakers. It does sound really good, but can't wait for her to hear the Nenuphar Minis. I'm planning on starting out w/o the subs. I don't think I'll need them with the Minis, but I've been really impressed with these subs and I generally don't use subs with 2-channel.

Any Nenuphar owners in NC, Virginia, SC or Georgia?  I’m really interested, but need to hear them in person before making a decision.  Of course I’ll wear a mask.  Thanks,

Don Ivey

@abd1 Congratulations on acquiring your Canary M90 amp. How soon will you receive your Nenuphar Minis?

The OP of this thread david_ten uses the Found Music 2A3 SET mono blocks with stellar performance results. No doubt room size and ultimate listening levels are variables.  Cube Audio pairs the Nenuphar with 45 and 2A3 SET amplifiers (Usually Tektron brand) at audio shows throughout Europe.  These pairings consistently receive high praise.
Charles 

At many audio shows, the Zu Audio room features their models playing hard rock and metal music playing at extremely high volume.  The speakers are quite capable at delivering at high volume levels.

Full range single driver systems cannot deliver that kind of volume level (the Nenuphars delivered plenty volume for my particular taste) and actually excel at delivering a vibrant sound at quite low volume levels.  Although they are not particularly efficient, they are probably efficient enough for use with some SET amplifiers if one does not demand extreme volume output or use in a very large room.  

Use with a single-ended 300B amp?  I don't know, I never heard them used with that kind of amplifier.  But, I guess they are not well suited for smaller single-ended amps, like those running 45s, given my experience with a 99 db/w 8ohm speaker (I've run this speaker with pushpull 45s, parallel SET 2a3s and pushpull 349s; single ended 45s were okay, but marginal with certain kinds of music).

Hi keithr, 
If I'm correct your experience with high sensitivity and efficient speakers has been predominantly Zu Audio.i am not questioning your encounters with them and various amplifiers.  I believe that the Cube Audio Nenuphar though not as sensitive as the Zu are an easier load to drive in real life/actual use. 

People seem to have more success with  low power SET driving Nenuphars compared to these same amplifiers paired with some Zu models. I believe that Srajan Ebaen alluded to this observation in his 6 Moons review of the Nenuphar. I understand that its 92 db sensitivity may lead some to question compatibility with low power SET amplifiers.  Numerous reviews and owners feedback say otherwise. 
Charles 

Charles, in my high efficiency speaker experience I consider 845s or push/pull triode to be more ideal for this efficiency level. Running low watt SET at high levels yields more distortion. Ymmv.

I acquired a Canary M90 push pull 300b amp that I’m going to try. It sounds great so far with some 85db 8ohm stand mounts that I have and that’s not an optimal pairing. Looking forward to how it sounds with the Nenuphar Mini’s. 

Hi keithr, 
 Why would that be the case? This contrary to what the Nenuphar designer and builder Grzegorz Ruika has stated publicly on several occasions. Low power SET with zero or low NFB were the intended type of amplifier to pair with. Is your concern the 300b or that it's an integrated amplifier?
Charles 

I would pass on a 300b integrated with these speakers. It might “work” but won’t be optimal. 

A possible / potential amplifier pairing for the Nenuphars, for interested parties:

http://www.myemia.com/50%20amp.html

There is a listing for the EM/IA Permalloy 50/300B monoblock amps and power supply at USAudiomart. The Listing Title is: "Jeffrey Jackson (Experience Music) 300b Type 50 Switchable amp"

Jon Ver Halen, the Cube Audio Importer, used the Type 50 version to drive and showcase the Nenuphar Minis at Capital Audiofest 2019.

[AVShowrooms Video]: https://www.youtube.com/watch?v=m0XFsF6RPfY

[Note: I do not know the seller personally; simply bringing it up as an option]

Agree, I think the Allnics could be a good match. If/when ready we have both the 10 inch and 8 inch Nenuphar’s you can try at home. Let me know.

Thanks @toetapaudio and thanks for your previous comments and input, maybe after the lockdown ends.

@david_ten and @charles1dad

Thanks for your replies, very much appreciated.

@david_ten - Not decided yet, still trying to make my mind up and and save up some money OR more accurately have the confidence to spend the money in these uncertain times.

And also the confidence to spend a large amount of money on a speaker I haven’t actually heard/demo.

Agree, I think the Allnics could be a good match. If/when ready we have both the 10 inch and 8 inch Nenuphar’s you can try at home. Let me know.

Based on the provided specifications (Modest level of NFB =6 and relatively low damping factor=10 and probably less into the 6 ohm Nenuphar) suggest a favorable match with the Nenuphars. 
Charles 

@yorkshireman Based on gut feel, I believe it will be a great pairing.

You will have to compare with another amp to determine how the negative feedback of -6dB and the -80dB S/N ratio play out for you.

Have you made a choice between the Nenuphar and Nenuphar Mini?

Coincidently, I recently considered a permalloy ’based’ amp. : )

Would the Allnic T1500 integrated 300b SET Amp work well?

Key Features:

• 10 watts per channel of pure class A high power output. The T-1500 MK2 is a single ended, stereo integrated amplifier. Almost all other 300B amplifiers are under, and distortion, driven. This is a result of the use of conventional “Resister-Capacitor” circuits, which give only up to around a 70V swing voltage, with high distortion. This means that an already distorted signal of a lower than optimum swing voltage is directed to the deep biased 300B grid. Allnic’s powerful “Inductor Drive” circuit gives up to a 150V swing voltage, with very low distortion (about 0.3%). It is this drive delivered to the T-1500 MK2 that allows for a higher output (10w) with much less distortion than can be expected from standard 300B circuits.

• Real power drive. The drive tube, 6SN7 is a moderate-mu (about 20) twin triode. We use this to drive the 300B’s via a choke plate inductor. Our choke inductor (100% nickel permalloy PC core) has very low power loss and infinitely high load impedance. This configuration is an ideal drive stage for 300B SET. And as the first tube, a twin triode 6SL7, has a very high-mu (about 70), the T-1500 MK2 has a total gain of +35dB.

• Nickel alloy output transformer. Allnic uses sophisticated ratio mixed nickel permalloy PB cored output transformers. Because of their extremely high initial permeability, it is possible to use fewer turns on the primary winding while retaining very high ‘open circuit inductance”. That means a resulting very wide frequency range and low distortion bass response. This is another reason why the T-1500 MK2 excels over other 300B integrated amplifiers. Allnic also uses a very big nickel core, so as not to be magnetically saturated at a high current level of 100mA.

• Long life and trouble-free operation. Allnic employs a “soft start circuit” to protect the tubes and other parts. It applies the high B+ voltage only after tubes are fully warmed-up.

• Self-bias control grid.

• Analog Power Tube Current Monitors. Allnic uses analog current meters to display the condition of each channel’s power tube. The meters make it exceptionally easy to see the status of each tube at any time and offer a simple, unambiguous indication of each tube’s status compared to conventional LED bias monitors.

• Natural negative feedback. The T-1500 MK2 applies about -6dB of negative feedback. This is a very complimentary amount of negative feedback that differentiates the Allnic 300B single ended amplifier from the standard, which has a very coloured and weak speaker driving force. With this natural feedback, the T-1500 MK2 has a relatively high “damping factor’, very low distortion, and a higher S/N ratio, without losing the signature single ended natural sound quality.

• We use a NEW remote controlled high quality 41 step silver contact attenuator Ver.2 (all resistors non-inductive) instead of a carbon filmed slide potentiometer.

• Beautiful 20KHz square wave response.

Technical Specifications:

• Output Power: 10w + 10w (4, 8 or 16Ω load, at 1KHz)
• Distortion: 0.3% at 1KHz, 2.83V
• Frequency Response: 20Hz – 20KHz Flat
• S/N Ratio: -80dB (CCIR, 1KHz)
• Damping Factor: 10 at 8Ω load at 1KHz
• Voltage gain: +35dB
• Input Impedance: 10KΩ (single-ended, unbalanced)
• Input Sensitivity: 230mV for rated power
• Tubes: 300B X 2 (power triode), 6SL7(6N9P) x 1 (First tube), 6SN7 x 1 (Second tube)
• Fuses:   AC Mains – 3A / 250V (110W) (two supplied – one is a spare). Tubes -0.5A, 250V, 20mm glass type
• Dimensions: (W x D x H) 430mm x 380mm x 240mm (17 x 15 x 9.5 in)
• Weight: 22kg net. 26kg shipping weight.

 https://www.hammertoneaudio.com/product/t-1500-mk2http://

Came across this video explaining damping factor while researching amplifiers. Coincidence(?) or is Google / YouTube keeping track... : )

A primer on damping factor from Hans Beekhuyzen:

https://www.youtube.com/watch?v=idxT7VVYyxo

[Note: if someone previously posted this, my apologies. Let me know?]