Hi cal, However you made a valid point. Negative feedback (NFB) level manipulation does affect these amplifier parameters. 1 Gain output decreases as NFB is increased.. 2 Output impedance decreases as NFB increases. 3 Damping Factor increases as NFB increases. Output impedance and Damping Factor have an inverse relationship. Charles' |
Hello,
Looking at the level of the stated distortion and accompanying output impedance and damping factor of >10 (Does this mean But <20?) is consistent with a zero NFB (Or very low level of NFB). So based on these measurements they suggest that (on paper) this amplifier should be a pretty decent match with the Nenuphar. Only an educated guess as other aspects of the amplifier aren’t known. Speaker impedance =8 ohm ÷ output impedance of roughly 0.8=10 which is the DF (At least for 8 ohms).
Charles |
David,
Thanks for the link posting. Srajan Ebaen really loves the Elrog 300b and as a former owner I understand why. It’s interesting that an upstart 2A3 impressed Srajan to such a degree. This Lanlai 2A3 is roughly 1/3 The price of the esteemed Elrog..
Charles |
A very key aspect regarding the Nenuphar is it was designed 'specifically ' to be driven by SET amplifiers with high output impedance/ very low damping factor (DF). I could imagine a perceived "dryness" to the sound of this speaker if the amplifier DF is more than required for this unique speaker. It would effectively damp the life and "soul" of an already very damped/controlled driver with its exceptionally powerful magnet /motor unit. I suspect one wouldn't want or need a DF > 10 or so.
Charles |
Hi exlibris,
I get your point and understand the subjectivity we all experience with listening. No doubt that both the Nenuphar and Odeon horns are excellent sounding speakers but presenting their own individual sound/sonic character.
Charles |
David,
I’m aware of how much you have enjoyed listening to the Tekton D,I. SEs and your genuine admiration of them. I’ve heard the SEs and can vouch for their excellent sound quality. With the Nenuphar you’ve moved into a very different direction /realm of speaker design. From multi driver with crossover design to a single driver crossoverless design.
The SE has really good coherency,openness and transparency for a multi driver speaker. These parameters are the purported areas of strength of a single driver speaker. Within this genre (single driver) there is a hierarchy of quality and implementation. By reliable sources the Nenuphar is in the uppermost tier for single driver speakers. They may offer a level of sheer purify that few or any multi driver speaker would be able to match.
Reportedly the Nenuphar has simply stunning good midrange purity/tone/transparency (speaker just disappears) without sacrificing exceptional performance in the bass and upper frequencies. Quite an accomplishment that many other single driver speakers fall short of achieving. Having become accustomed to this premium level of single driver execution/sound quality I could imagine that even a ’very’ good multi driver (with its necessary crossover components) may in direct comparison sound veiled and flatter/less alive.
The 10" driver used in the Nenuphar is said to be unique and superb with its very powerful magnet/motor assembly. I do not consider your comments of comparison a knock on the Tekton SE at all. It is competing against the very strengths of what highly executed single driver speakers are all about. Also factor in you are using the type of amplifier this speaker was designed to be driven with. Your Found Music 2A3 SET is an ideal choice.
Charles |
You wouldn’t want your preamp output impedance to be more than 1/10 (preferably 1/20th) of the amplifier’s input impedance. Al’s correctly points out that some tube preamps have output impedances that can exceed that level (particularly at certain frequencies). Good warning from Al. Not an issue with nearly all solid state preamps. To be clear divide the amp input impedance by the preamp output impedance. Charles |
I wouldn’t make the assumption that the Cube Audio Nenuphar suffers from some "common" whizzer limitation. Based on all accounts I’ve have been exposed to the Nenuphar is in a completely different category of performance/design success. Generalizations don’t apply here.
Charles |
Hi deepfield,
Thanks for posting your listening impressions of the Cube Audio speakers. I do not doubt a word you have written. If I were to ever change my speakers the Nenuphar would be my choice. This Polish company in my opinion has raised the bar for premium tier single driver speakers. I'm also curious to know what amplifier you used to drive these Cube Audio speakers.
Charles |
Deepfield,
Thanks for your reply. You have a very nice collection of amplifiers.
Charles |
Steakster,
I also believe that David's audio system sounds "absolutely stunning ". A first rate signal chain (Denafrips, Grandinote Genesi and Found Music 2A3 SET) and the purity of the Nenuphar. My gut feeling is that the level of naturalness, tactile realism and subsequently deep emotionally involving/connecting music listening experience is simply sublime. No doubt in my mind that this system pulls you into the music and keeps you there. IMHO this is more difficult to accomplish and is more satisfying than Hifi spectacular objectives.
Charles |
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
|
Yes I wondered the same in terms of the exponential (10x) change in the DF value with just a simple resistor addition. I'm surprised that its of such magnitude. But in practical terms the sound quality did improve.
Charles |
Hi bebruatigan, You experienced a very dramatic form of the 'break-in' process. I am glad you had the patience to give the Nenuphars a chance. Some listeners would have come to a premature conclusion and given up on them. I have no doubt that your are hearing superb sound with your new system. Congratulations and enjoy this for many years. Charles |
Hi sale84,
Your situation is totally expected and predictable.
The designer/builder has clearly stated the Cube Audio Nenuphar is specifically meant to be used with amplifiers possessing
1 little or no NFB
2 Relatively high output impedance
3 low damping factor (DF)
The special single driver has a very powerful magnet/motor assembly and is very well damped and controlled. An amplifier that utilizes high levels of NFB which results in very low output impedance and high damping factor is exactly what you need to avoid.
It is no surprise the superb Nenuphar speaker sounds magnificent with a high quality SET amplifier (Most often zero NFB) such as your Line Magnetic 845 or David_ten’s teriffic 2A3 SET mono blocks. High NFB amplifiers (which yields very low output impedance) are detrimental. IMO the Nenuphar is worth every penny based on feedback I’ve received. BTW solid state amplification are fine as long as they adhere to the designer’s recommendation/ guidelines.
Charles |
Saleh84,
Your Gryphon is an excellent amplifier "with the right speaker". Some speakers demand amplifiers with high current delivery with lower output impedance due to low and difficult to drive load characteristics and often steep phase angles. The Nenuphar is the antithesis of this type of speaker. Your LM 845 wouldn’t be a good choice with these current hungry speakers. I much prefer your LM /Nenuphar approach.
Charles |
David, I'm not surprised that stepping up to a higher quality better engineered brass spike would be noticeable. Better vibration/resonance management is a worthwhile pursuit. Particularly a speaker the high caliber of the Nenuphar will easily reveal the differences. Charles |
Hi toetapaudio,
Other than presumably lower frequency region differences, have you heard other sonic distinctions between the 8" and 10" Cube Audio drivers in your showroom system?
Charles |
Toetapaudio,
Thanks for your thorough characterization of these two what I believe are spectacular speakers. I really think that these Cube Audio speakers are cut from a different cloth compared to other single driver wide band speakers. I don't doubt that they sound splendid with transistor amplifiers that avoid over use of NFB and unnecessary damping factor levels. Srajan and Cube Audio have clearly emphasize this point.
Charles |
Stephendunn, With the stated output impedance of your OTL amplifier I suspect you're going to have a very fine match with the Nenuphars. Congratulations and I look forward to your upcoming listening impressions. I believe you'll be quite pleased with what you hear. Charles |
Hi Steve, Congratulations! I believe you have made a wonderful decision in choosing the Nenuphar. Based on what I've been able to learn about this speaker from owners and reviews I feel it sets a new upper tier standard among single driver speakers. Given your current components and power amplifiers, IMHO you will have superb sound quality and beautiful music reproduction. If I were constructing a new audio system today I'd begin with the Nenuphar. Charles |
Steve, I believe at a lower price point the Tekton Perfect SET and the Canadian Coherent Audio speakers may have come close to your wish list. However when many factors are taken into consideration the Nenuphar remains very formidable. I just get the sense this speaker personifies 'naturalness' which is a quality many speakers fail to achieve. Charles |
On paper I don't see what would make the Gryphon Diablo a particularly good match with the Nenuphar given the specific design objective of this speaker. However as has been shown before there's no substitute for actually listening and judging. I don't know why granite would necessarily be superior to the original Nenuphar cabinet. This is a very well thought out cabinet to match the superb driver and no doubt is a major factor in the overall sound quality. Charles |
Stephen, Thanks for sharing your initial listening impressions, you obviously had quite an enjoyable and insightful experience. It will only improve from its excellent debut. I have no doubt the Nenuphar sounds fantastic with either of your amplifiers. It’s great to read that you are presented with such realism and ’completeness’. You must be thrilled with your decision to purchase these superb speakers. "a feeling of encountering the real thing" That sums it up beautifully. Charles |
I’m curious to know how the Schitt Aegir pairs with Nenuphar. On paper it seems an undesirable match given its low output impedance and very low THD figures which suggest generous use of NFB and very likely high damping factor (DF). Cube Audio intentionally designed the Nenuphar driver to be compatible with amplifiers the opposite of this. 6 Moons reviewer Srajan Ebaen confirmed this with his multiple amplifier comparison driving the Nenuphar. The higher the output impedance the better the sound/match. The ’highly controlled (very powerful magnet/motor assembly) driver needs very little DF to function at its optimal performance.
However the proof is in the ’listening’ and there are always exceptions to measurement predicted outcomes. khragon’s listening impressions will be insightful and I look forward to reading them. |
David both reviewers basically just confirm what the Cube Audio owner/designer so openly shares with everyone willing to listen to him. That extraordinary driver he painstakingly developed simply doesn’t need a NFB amplifier with gratuitous DF levels (low output impedance) to control it as many other speakers do benefit from. Frankly I am surprised that the PS Audio BHK amplifier has such a high DF (>350) that’s a lot of NFB being utilized in that circuit design.
Nevertheless wouldn’t it be something if both of khragon’s amplifiers sound terrific driving the Nenuphar? This speaker fascinates me. David I can easily understand why it sounds superb with your 2A3 mono blocks or the LTA Ultralinear amplifier mentioned earlier above.
Charles |
The Klipsch is a high sensitivity speaker yet may possibly benefit from more power due to crossover design and big woofer control. The crossoverless, very easy to drive load Nenuphar is a different animal. S.I.T. 3 amplifier and Nenuphar is considered to be a splendid pairing. As they say, "horses for coures".
Charles |
cal,
I suspect that the F4s would quite likely work out well with the Nenuphar. I'm somewhat surprised you preferred them over the Atma-sphere M60s and the Pass Labs XA 25 with your speakers. I get that the Frankenstein's 8 watts isn't enough for your PRE. The Frankenstein would very likely be an excellent match with the Nenuphar.
Charles |
In regard to cables. silver vs copper there are so many variables involved as cal alluded to. Either material can sound smooth and warm or cold and sterile. Quality of the wire, geometry, dielectric material chosen, connector selection, on and on. .I've had wonderful results with silver I.C.s and speaker cable in my system over the years and the Ocellia has been superb for me. Without question many could say the same about their copper wire experiences. Charles |
Cal,
You did it the right way by actually listening to various amplifiers in your own audio system. At that point you just have to trust your ears and 'know' what type of sound presentation you prefer. This stuff is so personal and that is what makes it fun and so interesting. Stephen you have two excellent amplifiers for your Nenuphars and listening impressions can and do change over time (particularly if burn-in is a factor). The First Watt S.I.T.3 is a formidable component. I just believe that the Nenuphar has remarkable purity and transparency (without being analytical) and reveals what's fed into it within the system. Charles |
David, The T+A’s reasonable DF level and its negligible NFB no doubt contribute to its perception/reputation of being a very organic sounding transistor amplifier compared to many other solid state brands. Also explains why it pairs so well with your Nenuphars. I guess it comes down to what someone desires as some amplifiers are touted for their DF greater than 1000!!! This is viewed as a + attribute. Charles |
khragon,
Nice ! It will be quite interesting to read how these very different amplifiers sound paired with your Nenuphars. I believe this will be a very enjoyable endeavor.
Charles |
@vinpic
it does not lose anything (the mid-range magic is fully there), sound is thicker across the entire spectrum (more presence / more meat around all bones) which increases the sense of naturalness & flow. I did not have to tweak my system in any way (MU1-Tambaqui-Icon4se-Amp23r or SIT3, LessLoss cabling), the V2s are here to stay!
I have to say that listening assessment is quite informative. Actually more encouraging than what I inferred from Srajan Ebaen. Of course two different audio systems heard by different pair of ears. But is this not always the case when subjectivity trying to communicate to another sonic/music listening impressions?
To know that it retains the "Midrange magic" with added meat on the bone is an accomplishment. Of course depending on one’s current audio system voicing the additional meat on the bone may not be required. So as always the final judgment is individually determined by targeted sonic needs and goal.
Charles
|
@vinpic
Btw, when prompted, Srajan preferred the V2 (scroll down few letters till you find the one on Nenuphars V2)
https://6moons.com/lettersandfeedback
Yes he did and I’m not disputing that at all. If my reading of his review was accurate, he seemed to imply changing to the v2 drivers might very well necessitate changing current components in one’s audio system to match properly the v2 signature/character.
Your comments suggest that this may not be required in all v2 driver swaps. It is rather system dependant. Some v1 owners ’may not experience the brightness that you occasionally heard. Those with different source, preamplifier, amplifiers may feel that they have sufficient "meat on the bone " fullness already. That is my only point.
Charles
|
YOu see its things like this that leave me in doubts about **Cube Audio**. Something just aint smelling right about this company. Here they are blabbing their **all new cone is , so much better..**, yet give no details on how to go about taking old drivers out, shipping drivers to who knows where,,, who will pay ship cost both ways.. which carrier to use. Pre paid label?? How long turn around time, give or take 1-2 days..etc etc. Cube is leaving their fans in *The Lurch**, ,,canoe up s**t creek, w/o a paddle. IMHO I wouldn/t go for it. Its too risky,
What is risky? You can either use the distributor, dealer and probably deal with Cube Audio directly. I am pretty certain once initial contact is made all of the details are explained. I see absolutely nothing here to be suspicious of.
Charles
|
@jollytinker
Also, the magnets are so powerful that they can easily pull a hex wrench from your fingers when you loosen your grip even just a bit. The wrench will fly directly on to the edges of your whizzer cones with quite a bit of force. The simple answer is a non-magnetic hex wrench (believe its 4mm). I found one for 12 bucks on line and thought it was a small price to pay for the peace of mind.
This is wise and worthy advice for sure. That is some magnet!!!
Charles
|
Cal,
I’ve used various silver IC and speaker cable over the past 20 years. I’m currently using Ocellia silver cables the past 7 or 8 years. As with you I just haven’t heard the thin,bright or edgy sound supposedly attributable to silver. In fact the Ocellia is very refined, smooth, and organic yet quite open and nuanced. Exceptionally transparent/clear. Warmth rather than cool and sterile/clinical.
Interesting the improvement in your Coincident speakers as I know they use high quality 6N copper wire. Israel Blume (Coincident founder/owner) once told me he doesn’t care for silver. I respect his opinion but I’ve never had a problem with silver wiring.
IMO silver actually has a natural warmth (But not gratuitous).I’ve always been curious as to how my Coincident Frankenstein 300b and their Statement Line Stage would sound with silver internal wiring. But I’m very happy with both and left well enough alone.
Charles |
Cal,
That referral to 6 Moons is a good idea. Srajan Ebaen has been an admirer and user of Zu speakers for quite some time. He has reviewed a number of their models very favorably thorough the years.
He was very taken and struck by the Cube Audio Nenuphar and seems to place them in their own singular uppermost tier category for single driver speakers . He is astonished by their sound quality and presentation. Although Zu utilizes full range drivers I realize that it isn’t a single driver speaker as is the Nenuphar.
Charles |
Yet another example of why nothing substitutes for direct listening in your system (When possible). Some have had unimpressive results with high DF amplifiers and some excellent results. The Nenuphar designer and builder favors low DF amplifiers for these speakers. So while DF is a factor to be aware of there are obviously other variables that are impactful as well. This is what makes high end audio interesting, fun and sometimes mysterious. Listening trumps all.
Charles |
Excellent suggestion David. This would yield 4 different signal pathway options and no doubt that each would be distinct.
Charles |
Hi Cal and David,
It’s so easy for us to lay out things for Stephen’s audio system 😊.
Charles |
Stephen
Your findings closely mirrors the listening impression/ findings of Srajan Ebaen in regard to the bass performance as it relates to the DF. It does make sense when considering the design objective of the driver as stated by Cube Audio. I expect that the DHT Rossi preamp section will be beautifully matched with the S.I,T.-1 amplifier
BTW I'm very familiar with the Elrog 300b, a superb sounding tube.
Charles |
Hi Cal,
This respectful and helpful type of decorum and behavior was pretty much the norm in an earlier era on Audiogon. There have always been differences of viewpoint amongst posters on this forum. However the way in which they were managed was more mature and reasonable.
I really began to notice a change in interactions and increased trolling about 5 or 6 years ago. Not sure what's responsible for the evolution of this behavior but I'm glad it hasn't infiltrated this enjoyable and informative thread.
Charles |
Onhwy61,
Well, david_ten who has owned the Nenuphars for a couple of years could certainly chime in with some informed insight. Based on what I’ve read and heard about this speaker I’d say that probably 70% is attributed to the remarkable driver’s exquisite design parameters and its successful execution/implementation. Many hours and tedious effort along with extensive trial and error were required.
The speaker cabinet dimensions/geometry/physics and chosen material and construction technique probably account for the remaining 30%. If you carefully read the original 6 Moons review you will appreciate there was major effort needed to get the cabinet right. I believe that the cabinet plays a large role in the final sound quality that is not given suitable credit for.
The driver and motor/magnet assembly is an outstanding end result and would work beautifully in other DIY cabinets ( If well thought out ). But without question the special Nenuphar cabinet is a crucial aspect for this speaker’s resounding success. A ton of talent, effort, knowledge and patience went in to getting the Nenuphar right.
Charles |
debjit_g
Tektron offers quite a range. Besides 2A3 and 300b they have a 211 tube integrated amplifier. This is pretty unique. Of course they have a plethora of non DHT pentode type el 34, KT 88,KT 150,6550 models. etc.
Charles |
Stephen,
Congratulations!
It’s interesting that this simple step reduces the DF by a factor of 10 and improves what was already a very high level of sound quality. This was an excellent suggestion from the knowledgeable Vinnie Rossi. It certainly does stimulate the curiosity of what happens if DF is reduced to 8. Fun stuff.
Cal,
Since an amplifier’s DF and output impedance have an inverse relationship I wonder if this output impedance is ’effectively’ increased with use of the resistors or is the nominal speaker impedance as seen by the amplifier decreased?
Charles |
Hi debjit_g,
DF=Speaker impedance (In ohms) ÷amplifier output impedance.
So to lower the DF either the amp output impedance must increase (Denominator) or the nominal speaker impedance is decreased (Numerator). Unless there's something I'm missing. With amplifier specifications the lower the output impedance the higher the amp's DF. This usually reflects the amount of NFB employed in the circuit.
Charles |
V1 or V2? Still a great speaker either way.
Agreed, and I strongly believe that preference is dictated by associated audio system components and the signature or voicing sought by the listener. A First Watt F5 amplifier owner may prefer one, and a Shindo amplifier owner may prefer the other.
Charles
|
Agree that if the power amplifier was encountering a speaker impedance of less than 1 ohm (0,89 ohm) this is an enormous challenge for 'any' amplifier to manage. In fact most amplifiers would be incapatible of delivering the vast amount of current demanded by this low of a speaker impedance. There has to be an alternative explanation.it just doesn't seem as though this usually low speaker impedance if seen by the Vinnie Rossi amplifier would result in improved sound quality as reported by Stephen. Al (R.I.P.) we miss you.
Charles |
Keith,
I don’t believe that anyone is going overboard in regard to the damping factor (DF) variable . The Nenuphar manufacturer himself has clearly and often discussed the inherent damping of the unique driver. He has explicitly stated the driver is purposefully designed to be used preferably with high output impedance amplifiers with little or no NFB and thus a low DF. Stephen unequivocally hears an improved sound quality with the substantial lowering of the DF of his Vinnie Rossi hybrid amplifier.
No here is disputing that low output impedance amplifiers with higher DF can sound quite well driving the Nenuphar. In fact this point has been stated in this thread on more than a few occasions . Gryphon, Bakoon and Mola Mola as a few cited examples. I believe that folks on this thread recognize that Df is just ’one’ aspect but nonetheless a relevant one.
Stephen’s recent positive experience of lowering the DF did naturally raise curiosity as to how one simple resistor could achieve this. Thanks to Stephen’s email response from Vinnie Rossi explains it for us. I and I believe most of the participants on this thread seek further education on technical matters that so obviously impact sound quality.
I don’t find Srajan Ebaen’s listening levels to be an impediment to providing meaningful reviews. BTW I’ve had limited exposure to the Swiss Boenicke and I think they sound exceptionally good.
Charles |
