@noble100
Thanks ! Appreciate the response.. I have the pass XA25 which gets really warm, but it’s not a room heater like the higher output XA amps can be. I’m in NC too, which is why I eventually let my BAT VK75SE monos go. I was using various class D amps during the summer months. Those were driving my Vonschweikert VR7’s. Have since moved on to some Daedalus Speakers which are 95db sensitive, but need current to come alive. The Lil pass does a good job and sounds SET like without melting the surroundings. Been a great hobby during all the home time.. |
Hello bluorion,
It seems like you'd like thread posters to focus their attention and advice to your original OP subject. Which I believe is that you're curious about whether your overall system sound quality and performance would improve by utilizing a good quality and high powered class D amp, or pair of monoblocks while using your Luxman integrated's preamp section. Here's my take:
In my experience and in general, high quality class D amps have a very neutral and detailed presentation, like the audio ideal of a 'straight wire with gain'. I believe this is mainly due to their inherent very low distortion levels, very low noise floors and voicing decisions made by the amp's designers, for example Bruno Putzeys, I think other high quality class D amp module desingners have followed Putzeys lead in prioritizing accuracy in their designs.
Some prefer this very neutral and accurate quality while others prefer a bit or more of coloration in their overall system sound. Audio enthusiasts have various terms for these preferred colorations, such as 'warmth' or bloom', but they all typically require the amp design to emphasize even ordered harmonics, which humans perceive as euphonic, and attenuate odd ordered harmonics, which humans perceive as not euphonic, in their designs It's also important to note that music itself can have varying degrees of euphonic qualities that we perceive. And that the accuracy or quality of the music recording/mixing process can also either enhance or detract from the music's inherent euphonic qualities we perceive.
Personally, I've discovered it's best to view overall system sound as a continuum from very accurate and neutral to not accurate and colored. I believe it's important to actually audition and experience different systems along this continuum to gain a better understanding of the differences in overall system sound qualities possible and which you prefer.
I apologize for the length of this post but I know, from a lifetime of personal experience, that finding and creating an overall system sound quality that you really enjoy is complex and full of subtle shades of gray in practice. I make no claims of simplicity in my journey or your possible journey.
Nevertheless, I do have a few suggestions that are likely to shorten and simplify your pursuit:
It's an asset to be adventurous and to not be overly hesitant to try new or different technologies, ideas or things in general.
I know I learn and understand best through personal experience, perhaps you do, too. Trying new and different things are a good way to not only discover what you like and enjoy, but also what you don't like and enjoy. A good example is your idea of combining the high quality preamp section of your Luxman integrated with a high powered and high quality class D stereo amp or pair of monoblocks.
From your earlier posted list, I would recommend you begin your journey by trying either a D-Sonic stereo amp (starting at $1,475) or pair of monoblocks (starting at $2,250/pair). I suggest you call the owner, Dennis Deacon, describe your idea and ask for his advice. He's a good guy, very knowledgeable and honest. I know his M3 amps are very good, with very detailed but smooth midrange and treble performance, because I own the M3-600-M monoblocks. He told me the newer M3a amps are even better but I appreciated his honesty in also stating the improvement over mine were subtle and probably not worth the expense of upgrading.
He offers a 30 day free-in home audition period with a no questions asked return policy, so there's literally no financial risk. I have no association with D-Sonic, I'm just a big fan.
Lastly, I want to mention that the quality and audible sonic characteristics of the preamp utilized with good quality class D amps is extremely important because these qualities are the major determinants of the overall sound quality perceived, since the D-Sonic amps are just going to faithfully amplify the inputted signals without adding or subtracting anything perceptible.
I can relate the very different overall sound quality presentations resulting from the different preamps I've utilized in my system with the D-Sonic monoblocks, ranging from a VTL 2.5L with NOS Mullard tubes swapped out to a few other solid state preamps, if you'd like.
Best wishes,
Tim |
many many good points made by noble100 in his lengthy post below
-- know that utter transparency is often not the path to musicality of presentation in a hifi system -- sympathetic coloration is frequently the magic ingredient
-- preamp/linestage feeding class d amp is key to sq (corollary is driver stage of the class d module affects the amp’s sound greatly)
-- hear enough of what’s possible and learn about yourself and what you like and value in terms of sq
-- pleasing others, seeking measured accuracy, pursuing ’straight wire w gain’ is often missing the point - which is to assemble a system that plays music so beautifully it moves us makes us smile and feel great
|
@noble100 @jjss49 Thanks for the advice and you made a lot of great points. Yes, I'm still learning and experimenting on my audiophile journey. I've never been an impulse buyer and try to do as much research as I can without over doing it. Funny you mentioned D-Sonic, That's at the top of my list and I may try the monos since that's something I've never done before. If times were different, I'd be going to brick and mortar stores to audition all day (like I used to back in the day). Well, the town I live in has 1 store and the customer service is questionable at best. So having a 30-day trial period is nice. W4S offers a 45 day trial---that was another one on my list. The ICs I'll be using with the amp will be Audioquest Big Surs. Do you recommend any particular brand with the D-Sonics? Again, thanks for the thoughtful posts. |
jjss49:
"
know that utter transparency is often not the path to musicality of presentation in a hifi system -- sympathetic coloration is frequently the magic ingredient."
"
pleasing others, seeking measured accuracy, pursuing ’straight wire w gain’ is often missing the point - which is to assemble a system that plays music so beautifully it moves us makes us smile and feel great."
Hello jjss49,
Very good clarifying comments, too. Thank you. I think we're in complete agreement that the enjoyment of listening to music on an audio system is based on it sounding pleasurable. I think we're in disagreement, however, on whether some sort of system coloration is required, described as euphonic coloration by myself and sympathetic coloration by yourself, to perceiving the overall sound of the reproduced music as sounding pleasurable or if it can also be achieved through the accurate and neutral reproduction of well recorded music that is inherently euphonic or pleasurable.
A fine distinction for certain but also one that I think is very important to make and understand. I was actually referring to this distinction in my last post when I stated:
"I can relate the very different overall sound quality presentations resulting from the different preamps I've utilized in my system with the D-Sonic monoblocks, ranging from a VTL 2.5L with NOS Mullard tubes swapped out to a few other solid state preamps, if you'd like."
Let me explain more thoroughly by relating my experiences with 3 very different preamps I've used with the same pair of D-Sonic M3-600-M class D monoblocks that I can best describe as being powerful, 600 watts each into 8 ohms/1,200 watts each into 4 ohms, very low distortion, with a very low noise floor that have a subjectively and objectively very neutral overall sonic presentation. The other consistent factor in my system is the digital source recordings and equipment, consisting of a combination of ripped Redbook cd APE and hi-res, 24 bit 96 KHz FLAC files stored on a NAS (network area server) hard drive, an Oppo 105 universal disc player serving as a dac and a laptop running JRiver software as the controller/graphic user interface, with all components communicating via wi-fi:
Preamp #1- A VTL 2.5L line stage only preamp with a fairly expensive set of 4 NOS(new old stock) Mullard tubes swapped out for the originally supplied set of 4 Russian or Chinese tubes. This was my initial preamp on my class D audio amp journey that I intentionally employed to impart more warmth, bloom and and dimensionality to the overall system sound quality in order to perceive music as more euphonic and pleasurable.
This worked well, as expected and I enjoyed the overall sound quality effects, of a combination of the euphonic or sympathetic coloring qualities of a tubed preamp with the very neutral qualities of class D amps, successfully for 2-3 years.
Preamp #2- A solid state Oppo 105 universal disc player utilized as a preamp. This was mainly done due to my desire to streamline my system and only after carefully comparing my system's overall sq with and without my VTL preamp being utilized. To my great surprise, I discovered that I perceived my music and overall system sounded as just as sweet, warm and dimensional without the VTL tube preamp inserted in the signal chain as it did with it in the chain. I never imagined this would be the result, thought the VTL would be a permanent part of my system and was more than a bit perplexed. But I had to trust my ears and extensively compared results. So, I removed the VTL from my system and sold it to a good friend who was, and still is, very pleased with its performance in his system.
This streamlining was only possible because I only had a single digital music source and the NAS hard drive was already connected to my Oppo 105 via its USB input. I was also still able to use the Oppo to play cds, sacds and dvd-A audio discs as well as BluRay HD video discs. I believe the audio performed so well through the Oppo because of its exceptionally high quality, low distortion, low noise. highly isolated and very neutral preamp section.
The overall system sound quality effects of my streamlined solid state system creation, combining the very neutral, high quality, low distortion and low noise attributes of the Oppo 105's ss preamp section with the very neutral, high quality, low distortion and low noise attributes of the D-Sonic class D ss monoblock amps, also worked very well but the results were completely unexpected, at least by myself, since this combination still managed to convey the sweetness, bloom and warmth of the music if these qualities existed on the original music and the recordings quality level was sufficient to capture these qualities.
Preamp #3-A Mark Levinson 326S line stage only ss preamp. This is my current preamp, the 3rd I've used with my class D monoblocks, my favorite thus far and the one that has the most interesting pre-Covid story for its use in my system.
I was visiting my favorite local hi-end audio shop here in Indy, Audio Solutions, on a Saturday afternoon as I like to do every few weeks to chat with the owner, Graham, and see and hear what's new and interesting. He was demonstrating a pair of Magico A3 and Sonus Faber Stradivari speakers to a good customer from Montana who was trying to decide which pair performed best and which to purchase. The customer saw me and asked if I cared to join him in the audition and help him decide and I quickly agreed.
Graham was using a large class AB Mark Levinson amp with a ML 326S preamp and hi-res 24/96 and DSD music files fed through a Lumin D2 dac/streamer for the demos, in order to match Montana's actual system electronics. After Montana and I listened to each pair of speakers for about 30 minutes, I couldn't stop being impressed by and praising the truly amazing stereo soundstage illusions both pair of speakers were able to create with admittedly very well recorded and hi-res source material. The soundstage I perceived from the sweet spot position was of normal width, but was especially deep, detailed and layered. Images were solid, stable, very realistic and amazingly palpable. At first I thought it was the high quality and precisely positioned speakers in a well treated room that was responsible for this astounding stereo soundstage illusion.
But Montana said he was shopping for better looking speakers, that also performed very well, to replace his beloved pair of Avantgarde Acoustics large horn speakers that his new bride insisted must depart her new living room. He also seemed less impressed by both the Magico and Sonus Faber ultra-realistic stereo soundstage imaging abilities than I was. I finally asked him about this and he said he achieves even better sound staging results with his Avantgarde horns in his well treated living room.
He said he thinks he's become accustomed to the great stereo sound stage imaging but that, while he thought that high quality and precisely positioned speakers along with a well acoustically treated room were also very important, he attributed the addition of the ML 326S preamp, the Lumin D2 dac/streamer and better quality and higher resolution recordings as the main factors in achieving such stunning stereo imaging results in his system. Really, and Graham agrees? Well, what do you know?, I just happen to have a pair of high quality Magnepan 3.7i speakers in a well treated room and half a hard drive's worth of very good and higher resolution recordings. An idea's forming but do I really want to spend $10K on a preamp, un-streamline my system by reinstalling a regular preamp, spend another $2K on a Lumin D2 and hope I can achieve the same excellent stereo imaging results in my room and system?
Anyway, we both agreed that the Sonus Faber had more bass but the Magicos had higher quality bass, he said he already had a pair of REL subs that he used in the room, we both agreed once again that the midrange, treble and imaging performance were very good on both speakers, he bought the Magicos and Graham told him he'd ship them to Montana on Monday.
After Montana left, Graham broke the good news; he just took in a ML 326S preamp in very good condition on trade that he'd sell to me for half price. So, I bought the preamp and a new Lumin D2 at a small discount.
Well, that was easy!
So, jjss49, what you ask is my long winded point?
Remember your quotes that I requoted at the beginning of this post, that you probably read about a week ago when you began reading this post? Long term memory abilities vary, so here they are again:
"
know that utter transparency is often not the path to musicality of presentation in a hifi system -- sympathetic coloration is frequently the magic ingredient."
"
pleasing others, seeking measured accuracy, pursuing ’straight wire w gain’ is often missing the point - which is to assemble a system that plays music so beautifully it moves us makes us smile and feel great."
After recalling my personal preamp and class D amp journey in more detail, my main point is that I still agree with your first comment, but I've now changed my mind about disagreeing with your second comment and only partially agree.
I agree that the main point of assembling an audio system is that it "plays music so beautifully it moves us makes us smile and feel great." But I believe my current ML preamp performs so well because it does generally sound very neutral, like a 'straight with gain', but it also somehow seems to round off the strident highs and add a touch of sympathetic coloration at the proper times and to the proper notes.
Of course, I know this partial coloration and timing is not logical. I think a more accurate description of the dynamics at work is likely that the preamp is constantly adding a touch of sympathetic coloration or euphony and the music inherently possesses, creates and/or conveys its own perceptions of sympathetic coloration or euphony at specific moments.
And at times they probably must occur simultaneously and we perceive the music as exceptionally euphonic and pleasurable at these moments. It would be interesting to know if this can be measured to determine how often they actually do coincide.
Sorry I wrote a book.
Later,
Tim |
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@noble100 - I'm wondering if part of your improved satisfaction having inserted the ML preamp in the chain is a lower impedance, stronger drive capability of the preamp compared to the Oppo.
I've found that even a very neutral preamp with a fairly high current, low impedance output stage can sound much smoother and more natural, while still sounding very detailed, than when it is out of the system. |
Probably already mentioned but how about Lyngdorf? |
@jaytor @noble100
i agree that a huge benefit of an active preamp/linestage is impedance matching -- this has a real impact on the sound we hear - the impedance matching and compatibility between 2 devices in a signal chain is something that is often underappreciated, is difficult to measure and gauge without careful listening
noble, i also agree that your levinson unit is doing what it is doing all time, it doesn’t know what is passing through it... that been said, signal rise time, slew rate, power supply stiffness and speed are all attributes that affect transient response and clarity in any amplification device/buffer -- and the way a good linestage does this can be so helpful in a mild ’rounding out’ of the sound (esp. at higher volume levels) that in turn pleases our ears a great deal... |
Missing from the calss D story is, of course, the linear A/B amp is what allows for such a great stereo image. Note the story stops at having purchased the preamp. I trialed a dual-mono stereo D-Sonic; didn't like it so sent it back. I recall being happy with the strong dynamics and powerful grip, but if I recall correctly they had bad imaging as with most class D I've tried and a messed up / unconvincing midrange, again as with most class D -- dry and thin. They also had a really weird unstable soundstage while they were burning in. And finally, the Achille's heel of class D, the deadly lack of musicality / engagement.
Unlike the D-Sonics (Pascal modules I believe), the VTV Purifi I'm trialing now has mediocre dynamics -- something I'm sure would be improved with a monoblock or dual-mono system. Unlike other class Ds I've heard, the Purifi seems to have taken steps to return richness to the sound, and this is somewhat successful IMO. The midrange is unconvincing / sloppy / blurry. Imaging is...present but not wonderful. Possibly better input buffers would improve this. There is some depth and height, but width isn't that great, doesn't extend past the outside edge of the speakers. Imagine solidity is okay. I fear that the lack of musicality is still a problem; all today I didn't feel like listening, that's a bad sign. When I have sat down to listen, I don't feel like I'm being engaged / drawn in. Up until now I've been willing to overlook that for the sake of burn-in but it's getting to the point where I'll have to accept that burn-in isn't the issue.
I'm bringing in another Odyssey, this time a Kismet that's 3 years old. It's used so there shouldn't be any burn-in required. I suspect it's going to crush to VTV, but we'll see. It's coming tomorrow. I'll be sure to update everyone on my findings.
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Hello madavid0,
I have the D-Sonic M3-600-M monoblocks, their previous model that I bought about 6 years ago and that utilizes Anaview/Abletec class D power modules. D-Sonic's current model are the M3A-600-M monoblocks, that utilizes Pascal Pro2 power modules. These are the same modules that Jeff Rowland chose for his very expensive, but also very positively reviewed, Rowland Continuum 2 integrated amp.
The owner of D-Sonic, Dennis Deacon, told me years ago that he determined that neither of these modules requires an input buffer and that performance and sound quality didn't improve when he used one, so neither of these models use an input buffer. He also stated he was forced to source newer class D power modules in the M3 monos model because the prior Anaview/Abletec modules were discontinued. He said he chose to utilize the newer Pascal Pro2 modules because he thought they offered slightly better sq performance but, overall, they sounded very similar to the older Anaview/Abletec modules.
I'd suggest you consider either a used pair of M3 monos, if you can find a pair for sale, or a new pair of theM3A monos. I can state with certainty that neither of these amps have any of the deficiencies you described. In fact, I consider their exceptionally smooth and detailed midrange and treble performance, along with presenting a 3-D stereo sound stage illusion with very solid, stable and palpable images, as two of their main attributes.
While it's true that these are only two of the numerous positive attributes these amps possess, they're also two of my favorite and must have attributes in both a peamp and an amp. I definitely enjoy these qualities far too much in a home audio system to even consider buying any preamp or amp that lacked them.
Hopefully, your used Odyssey Kismet amp will also possess these qualities in spades.
Merry Xmas,
Tim
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I didn't feel like listening I think you hit the nail on the head. Some 35 years ago I purchased from a gentleman who after our 1st 2 transactions became a friend who shared what was valuable and I've found to be true, that any gear we have should make us *want* play music more. Everything else (soundstaging, detail, bass, etc etc) is just icing. We freely lent each other gear to try out for a while to see longer term what gave us the *feeling* of "I almost can't wait" to turn on the gear. I've found that *sensing* so to speak, to be the "magic" and can get lost when swapping pieces in search of improvements in resolution, soundstage, bass, etc. After all these years, I still miss the higher noise/hiss Infinity FET preamp I bought from him and traded to someone else that brought a Bedini over. FWIW, They had a well used grand piano that his wife played and how I discovered Maggie Tympanis and ARC gear, I carried in amps too heavy for him lol. |
bluorion: "So having a 30-day trial period is nice. W4S offers a 45 day trial---that was another one on my list. The ICs I'll be using with the amp will be Audioquest Big Surs. Do you recommend any particular brand with he D-Sonics? Again, thanks for the thoughtful posts."
Hello bluorion,
I've read good reviews on the W4S class D amps but have never personally listened to them. I'm much more comfortable recommending the D-Sonic M3 monos mainly because I've been using them for over 6 years now with 2 different pairs of main speakers, originally with Magnepan 2.7QRs and currently 3.7is, and they've performed exceptionally well on both. As far as I know, a comparable pair of W4S monoblock amps could perform just as well or even better than the D-Sonics. You'd probably need to home audition both with your Luxman to find out for certain.
If you'd like more than 30 days to audition the D-Sonic amps, I know if you call or email the owner, Dennis Deacon, and request a longer free in-home trial period, he typically extend the time period upon request.
Your Audioquest Big Surs are high quality cables and should perform very well as ics. I use custom balanced xlr cables as ics but I believe you'll need to use unbalanced rca cables due to the pre-out connections utilized on your Luxman. The D-Sonic amps offer a choice of inputs, balanced or unbalanced. with a switch also required to be set appropriately on the back of each amp.
Later,
Tim |
I purchased a Rotel class D five channel amp (RMB-1575) just for curiosity. It’s a very honest 250 wpc @ eight ohm and 500 wpc @ four ohm. I have it connected to my RBH Reference system, a pair of SV-T2, a SV-6200c and two 770 mounted rear wall. Their all four ohm.
It sounds incredible and can it ever shake the house. It’s a beautiful sounding amp and I’ve enjoyed it also in two channel mode.
.........however, I replaced it with a Crestron CNAMPX-7x200.....a 100lb block of AB power. This amp is incredible sounding at 350 wpc x seven channels. It’s suprised me that the Rotel was not totally spanked. It’s just so light and cool to touch it seems wrong. |
Class D is the future. Boomers stop bashing it, its a maturing product now. PS Stellar 1200 is sweet, Red Cherry, Merrill at a lot more money would give any amp made today regardless of cost a run. Now a pure tube system and I mean pure tube, with tube rectifiers will have its own unique sound, and many enjoy that. But solid state vs. Class D well it’s a toss up when you here a well made class D. As I age class D will be for me, no more trying to lift 100 lb. plus amps, in fact if buying today I look more at class D amps then the big solid state Amps or tube amps in the 30-60 lb. range tops. |
Hello phillyb,
I've shared, and continue to share, your enthusiasm for high end class D amplification for over 6 years now. Class D, in my experience, not only has the clear advantage over more traditional amp types in size, weight, operating temperature, relative cost and electrical efficiency, it also provides excellent overall sound quality results that are already very competitive with the other amps regardless of type or price. I also agree with you that this amp technology is still in its ascendancy.
My only hesitation in universally and fully recommending class D amplification to everyone, is the concern that not everyone seems to share our enthusiasm in its sound quality performance.
Many individuals have claimed for years that they perceive deficiencies in the sound quality performance of class D amps and some have even developed and promoted their own theories as to why, such as georgehifi's consistent proclamations that the class D carrier signal switching frequency is too low and needs to be north of 1 MHz to avoid sonic artifacts in the audible range.
The main issue has been the reality that I, and apparently many other class D amp lovers/users, have completely failed to notice any of these supposed sq deficiencies in their own varied and preferred class D amps. This has naturally resulted in users doubting the sincerity of the class D amp naysayers' claims of sq deficiencies.
Yes, virtually all agree that there were sq deficiencies in much earlier examples of class D amps but not on the numerous better examples produced within the last decade or so. The truth is that if class D amp users perceive none of these claimed sq deficiencies in their own amp's performance then, by definition, none exist since our perceptions literally are each of our realities.
I still believe it's important to keep an open mind, however, especially in this hobby. So, even though there remains a complete lack of legitimate scientific evidence supporting these supposed claims of deficiencies in the sq performance of class D amps, I still don't think it's wise to dismiss the remote possibility that these sq deficiencies actually do exist and that some individuals may be sincerely perceiving them.
After all, it's well known that there are gaps in scientific knowledge and that there's a high probability that important future discoveries will be made about the dynamic and technical forces involved in class D audio reproduction and perception. Perhaps, it will be discovered that some individuals are just more sensitive to certain yet to be identified and measured characteristic(s) of class D amplification.
Because of the above, I strongly suggest that anyone interested in the high quality sq performance and other benefits provided by a high end class D amp, should audition one prior to purchase to guarantee complete satisfaction.
Enjoy,
Tim |
@phillyb @noble100 Such interesting dialogue. I admit I don't quite understand a lot of the specific acoustic specs, etc....but I enjoy reading others' opinions about them. It makes me wonder about brands such as Mola Mola, Merrill and JR that always get such rave reviews about their sonic qualities. Do they meet or succeed these sonic measurements that you mentioned---and do more reasonable class D brands (D-Sonic, W4S...) not meet these measurements? |
I liken Class D amps to streaming digital music. Both are new technologies, and both are maturing super fast.
Remember when cameras had under 10megapixels at the turn of the century? -Now you can get a 100mp back for medium format.
Not bad for less than 20 years.
B |
Following this thread and it's very enlightening. Too many good, thought -provoking entries to comment on. Curious if anyone has heard or compared a new gen Rogue Audio amp using their unique topology that deploys a tube "within" the Hypex module circuit (TubeD, tm)? Only the Dragon and Hydra amp have this. As D is quickly evolving, does this have merit, is it audible? |
@akgwhiz, PS Audio makes a Stellar M1200 using a tube driver and IceEdge 1200AS module. VTV offers a Purifi module with a tube buffer. |
Klh007, thanks. Will look at those too. Just wondering if the tube adds a real (warmth, harmonics) difference or not. In any of these designs. The notion of rolling to tune to a preference is alluring. I use an tube buffered R2R DAC and its a real handle to tweak with. |
Hello akgwhiz and klh007,
In looking back on my audio/video systems over the past almost 50 years and participating on this forum for the past 8 years, I realize I've learned a lot from reading but I believe I've learned just as much, if not more, from just being a bit adventurous and gaining more useful and relevant knowledge by seeking out audio and video experiences as much as I could.
As the hip and woke kids say today according to my addled, old man imagination:
"Get yer caboose off dat cushion and go for a good audition."
What does all this hipness have to do with the topic of tubes and class D amps on the previous 2 posts? Well, if you're curious, the best way to learn and experience the overall sound quality combination is to go for an audition, or take advantage of a free in-home trial period in your own system and room.
You be the sonic adventurer, learner and discoverer. There will be no need for verbal descriptions or using our less than accurate imaginations. You'll be able to very thoroughly know the actual sound quality results and make a very informed decision about whether or not you prefer a touch of coloration with your main dish character of very neutral typically delivered from a class D amp.
Best wishes,
Tim |
I THINK the tubes in PSA M1200s are specific. Not sure what the availability of other brands would be for rolling.
I have owned many different class D amps for over a decade. A few I would say would have benefited from a romantic tube somewhere in the system, BUT, D has gotten much better, especially in the high freqs, to where, IMHO, changing cables would be the better option. The Cable Company would be a good source to try a variety of cables
I have a Tweakaudio EVS 1200, which uses the same IcePower AS1200 modules as PS Audio M1200, but are highly tweaked by
Tweakaudio. No tubes anywhere in my system, and it's very detailed without being edgy
hth
|
@akgwhiz, I own a Rogue Medusa and rolling tubes makes a moderate but noticeable difference in tone, and extension at the extremes, I have a pair of Mazda 12AU7s in mine. |
They’re just 12AU7’s.
AVM use unique tubes in their integrated and power amps. |
Thanks for adding your experiences with D amps, specifically hybrids which hold my interest. I have a Sphinx integrated now and have 2 sets of tubes on the way to roll (including the Mazdas...). One thing I failed to mention, concerning auditions, is that I live in Anchorage AK. There is ONE store in town that has ONE Primaluna amp on the floor. Seattle is over 2000 mi away. Unless Best Buy counts! Sure, some shipping back and forth possible but likely a few hundred $ per pop in the returned case as many vendors treat us as NOT continental USA. Trying real hard to wittle down to a few lines/implementations. So far as I can tell, every line mentioned using tubes is using them as input buffers. Only Rogue is doing (apparently) it different in their TubeD models by putting them "within" the Hypex module. No EE here, but was wondering if thats potentially a sonic step change from their previous buffer input style models like the Sphynx/Paroah. OK, back to the thread. |
Based on the photos of the inside of the Rogue “tubeD” amp, the amp uses a standard class D module with a proprietary tube input stage and a linear power supply. |
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As I've said, I'm no EE but the board's "wiring" or circuit path into the Sphynx's modules seems infinitely less complex than what's going on in the Dragon board's circuits going into the Dragon's modules. Rogue clearly describes inserting the tubes somewhere within the module path, both in their product descriptions online and in several interviews and reviews online with designer Mark Obrien (one is at Dagogo site, another is at Positive Feedback issue 60). Just sayin. |
tweak1:
"
I have owned many different class D amps for over a decade. A few I would say would have benefited from a romantic tube somewhere in the system, BUT, D has gotten much better, especially in the high freqs, to where, IMHO, changing cables would be the better option. The Cable Company would be a good source to try a variety of cables
I have a Tweakaudio EVS 1200, which uses the same IcePower AS1200 modules as PS Audio M1200, but are highly tweaked by Tweakaudio. No tubes anywhere in my system, and it's very detailed without being edgy"
Hello tweak1,
You made a couple of excellent points I can tell came from personal experience:
1. Class D, in my experience, is so accurate and neutral that it facilitates the perceptions of how changes upstream in the system effects the overall system sound quality. This applies not only to more significant system changes, like the source components and the quality of the recordings themselves, but also down to smaller changes like in the ics and power cords utilized. In my opinion, this qualifies as very high quality transparency.
2. I've come full circle about my thoughts and perceptions of combining tubes with class D amps. I began by using a VTL 2.5L preamp with an expensive set of 4 NOS Mullard tubes swapped in for the standard Russian or Chinese ones. I used this for several years with my class D amps and liked it so much I thought I'd never take it out of my system.
But I happened to hear a Mark Levinson 326S ss preamp at a local hi-end shop. I was so impressed with its performance, especially the amazingly real stereo sound stage image it presented, that I bought a used one and tried it out in my system.
Well, the midrange and treble sounds just as sweet and euphonic as the VTL with NOS tubes and the palpably realistic stereo sound stage illusion the ML presents was just too good to resist. So, I sold the VTL to a friend and I haven't regretted it since.
So I've come full circle from thinking I had to have tubes somewhere in my system to discovering that my system without tubes can sound even better. The only qualifier is that it took a very good and expensive preamp to top the tubed VTL.
My current opinion is that tubes combined with a class D amp usually results in very good overall sound quality. But I also agree that the quality of the midrange and treble performance, on good quality class D amps, has generally improved to such a degree that tubes may no longer be needed. As usual, it'll probably come down to the specific and unique amp/preamp combination utilized.
Thanks,
Tim
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I'm no EE but the board's "wiring" or circuit path into the Sphynx's modules seems infinitely less complex than what's going on in the Dragon board's circuits going into the Dragon's modules. If you look at the photos of the Dragon the hypex module plugs into the board the same as any other input buffer board. The tubes are not inserted into the hypex board and the input buffer board doesn't look anymore complex, that's not to say something in the buffer board could be different but the tubes in no way are inserted into the hypex, it's marketing speak for look we added distortion to a perfectly good amp. |
djones51: I don't think that "insert" has to be literal! There is a myriad of pins on those modules that likely allow for other configs. Did you read any of the interviews provided or any others out there? I don't have a dog in this hunt, I'm just asking if anyone has any experience in comparing Rogue's basic tube buffered input style to their TubeD designs. As I've said, I live in an audio desert and shipping amps around gets kind of expensive quickly.
From Dagogo - MO: What is really exciting to me is that these amplifiers are much more than just a tube circuit in front of a class D circuit. We use only the modulator and mosfet output stage, and bypass all of the other circuitry on the amplifier modules we are using. We actually combine the tube and buffer stages with the output section, using proprietary circuitry that makes the output section perform like a tube stage rather than solid state. What is quite gratifying is that we have had numerous class D naysayers wind up purchasing them.
From Positive Feedback -
So I built what is a basic Hypex-type amplifier, as that was the baseline on one side; and then I guess our top-of-the-line Apollo mono-blocks were the design goal on the other side. I never started off to make a pure digital circuit; I just built one without the tubes in it—though I knew that wasn't what I ultimately wanted. But I wanted that as base line: like, okay, here's what the Hypex Modules sound like used as they were designed to be used, to build the same kind of digital amps that a half dozen other companies out there are building with the Hypex Modules, the big difference being that we only deploy the switching MOS-FETs on the output section of the modules and otherwise we bypass everything on the modules that Hypex supply that everyone else uses—we are not using the Hypex Modules' driver stages or their input stages.
Seems pretty evident to me that unless a respected and accomplished guy like M O'Brien is really being evasive, exaggerating or such, there is a decidedly different implementation of the tube portion and use of the Hypex modules, in those amps.
Lastly, I really don't care about the details and as it's been stated, likely correctly numerous times in this thread, it's all about the implementation details. This would seem to be a different implementation. Just asking about experiences of any audible differences within the lineup, due to this implementation.
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@grk, Tommy's Cherry amps are Class D. |
I'm not saying anyone is being deceptive all I'm saying is the signal manipulation is occurring in the Rogue buffer board not the Hypex modules. There are no wires attached to the hypex in either the Sphinx or Dragan which is supposed to be TubeD or something. |
I don't have access to the documentation for the Hypex modules used on these amps, but the connector is the same (except for one status line) as the Purifi module. There is no provision on the Purifi connector to bypass the driver circuitry. I suppose it could be possible to have jumpers on the card which would do this, but it seems unlikely since this circuitry (on the Hypex board) is an integral part of the feedback design that makes the Hypex module function.
The Hypex and Purifi modules do expose the outer-most feedback loop, which is designed to provide a feedback connection from the speaker connections (or as close to the speaker connections as is practical). This is generally connected to the speaker output connections on the buffer board. It could be possible that Rogue is adding circuitry to this path to alter the Hypex module's transfer function, or someone integrating their front end buffer inside this feedback loop.
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Operation is based on a non-hysteresis 5th order self-oscillating control loop taking feedback only at the speaker output. Furthermore, the NC500 OEM is an unbuffered amplifier leaving the implementation of an input buffer up to the manufacturer. The NC500 is practically devoid of any sonic signature so this external buffer is a good way of tuning in a “house sound”.
It looks like in the Dragon they use the NC500. I assume they’re doing what every other manufacturer that uses this module they’re adding their sound with theirs or a third party external buffer. IMO it’s preferable to leave the signal as transparent as possible and not muck it up with distortion but to each his own. |
It looks like in the Dragon they use the NC500. I assume they’re doing what every other manufacturer that uses this module they’re adding their sound with theirs or a third party external buffer. Or even better if your source has balanced output and enough gain, feed it direct into the NC500 amp modules with no buffers at all, like I did, with my NC500 monoblocks. This is the least distortion and most transparent/dynamic you’ll get Cheers George |
Ok so A) Sphynx is the regular tube buffered input upstream of the D module implementation and the Dragon is the TubeD, just to be clear. B) if by looking at a picture one can determine that bypassing select functions within the D module is not happening, then maybe so. If not, then having those differences is indeed a novel approach. And "We use only the modulator and mosfet output stage, and bypass all of the other circuitry on the amplifier modules" would seem to merit a listen or curiosity. After all, isnt it desirable distortions that make pure tube amps what they are anyway? |
Tidal Audio, unquestionably a leader in high end amplifier design, has announced their new amplifier. It appears to be Class D.
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Your source better have low output impedance as well. The NC500 modules are fairly low impedance on the input. georgehifi8,196 posts01-03-2021 9:17pmOr
even better if your source has balanced output and enough gain, feed it
direct into the NC500 amp modules with no buffers at all, like I did,
with my NC500 monoblocks. This is the least distortion and most
transparent/dynamic you’ll get |
I hope they are connecting the hot and cold feedback ,speakers, clip indicator, overcurrent and power as well. We use only the modulator and mosfet output stage, and bypass all of the other circuitry on the amplifier modules" |
Your source better have low output impedance as well. The NC500 modules are fairly low impedance on the input.
Any one don’t be scared off doing this if your source is up to the task, 2k input impedance for the NC500 is not so bad, many retail class-D amps are that anyway. Even a 50ohm source impedance is fine into that, most high gain good dacs are contenders for this hook up. And the best buffer is no buffer. My dac is 1ohm output with 200mA short circuit current, nowhere near full volume,
absolutely no problem
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@ kh007: Oops I stand corrected. Thanks!
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@grk, Tommy uses an in-house designed Class D solution instead of adding a custom buffer to off the shelf modules, and they sound terrific. |
bluorion:
You wondered about Mola Mola. Of this I can speak from experience. A pair came up locally for sale and I went to audition them. I was blown away by the dynamics at the seller's home, but unsure since the system and setting were very different. So the gentleman was kind enough to travel with me to audition the Kalugas in my system. Again, I was blown away.
They made my Revel Salon 2's sing and explode like nothing I had heard prior. They easily bested my current Classe Audio CA-2300, as well as the former PS Audio Stellar 300's. I put them in and out of my system comparing the Classe. I heard much more dynamic bass...tight and controlled..but also heard sparkle and sounds I had previously not heard.
Used, for under 7k. I now have added the Makua Preamp with internal Tambaqui. I believe it is the implementation of the the Class D technology, just as with any component, that makes it excellent or not. One should not evaluate all class D amplifiers as equal. I have my heavy amps downstairs...Audionet..and they are better. But the size, ease, appearance and sound of these Mola Mola components are winners! |
Isn't class D just prepackaged class ab? |
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Isn't class D just prepackaged class ab?
Na, they're HF power oscillators that try to make sound. Cheers George |
I was looking to change mine NAD C370 (For a class D amp) who had a faulty protection circuit which is fixed and some other nearby strategic capacitors where also changed for around 50,- Euro on cost an materials. Than it occurred to me that a total revision on my NAD was only 350,- Euro to make him even sound better (probable) an will last another 25 years or so. Another thing is i run 2 sets of speakers close monitoring an far-field the integrated preamp gives me all possibilities to use one of the 2 sets with one click of a button. If i buy a class D amp i have to consider too look for a new separate preamp involving cost. Another thing to think about if something go’s wrong (as with my NAD) spare parts are cheap an are there for the foreseeable future if a high switching class D amp containing probably also specific programed firmware (wich is not free availeble for upload) stops working it is likely you can dump it with in 10 years time.
So i think we don’t have enough reliability data regarding class D amp’s but for sure regarding technolgy, low energie use an sound quality Class D amp’s are the way forward imo
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