My NAD 3020 D proves your Class D tropes are wrong

Can someone direct me to a good source to get a better understanding of the differences in Class A, A/B, & D amplifiers? I thank you in advance.

Here you go, @allenf1963

https://en.wikipedia.org/wiki/Power_amplifier_classes

Can someone direct me to a good source to get a better understanding of the differences in Class A, A/B, & D amplifiers?  I thank you in advance.

Erik, if this is too much of a rabbit trail, please disregard. If you (or anyone else) are aware, how does the NAD SQ/design compare to Naim? I have an Uniti Atom on my desk, but considered the NAD.

Youd have to be more specific, and I haven’t heard that much NAD and almost no Naim at all.

NAD has been experimenting with Class D in their products. As far as I know, the hybrid Class D in the 3020D is in maybe 1 or 2 other products. The top end that NAD amps that I am aware of are pure Hypex modules without the hybrid components.

I have been a NAD fan for years. 

I considered the digital integrated and due to the focus on digital went with the C375BEE.  A feature based decision based on being able to connect analog sources.

I'm glad it fits your purpose because NAD continues to evolve 'ease of use features' in the product line while remaining a value per dollar performer.  I think the Master Series is feature packed, approachable and powerful system.  

@decooney I wish I could say I put a ton of time in. I may have listened here and there for less than 20 hours total in a few weeks. I did not switch speakers in or out. Here's the good news... ultimately when it came down to it (to the OP's) point I did not find the NAD to be that much different than the naim. In this listening area I sit close enough that I don't know more than 40 watts unless I really wanted the whole house to party. My naim was enough. I auditioned more so to see if I could hear any large different and possibly put the NAD in my other listening area where I do need more power. The benefits is that the chassis was so much smaller and lighter in weight. NAD makes an excellent class D amp and I really don't have much bad to say. I think the differences were so subtle. 

Erik, if this is too much of a rabbit trail, please disregard. If you (or anyone else) are aware, how does the NAD SQ/design compare to Naim? I have an Uniti Atom on my desk, but considered the NAD.

I use Genelec monitors with class d amps,  I don't know of a more
"revealing "  speaker. Not many here would like that setup not enough distortion but if you want to hear what's on the media,  good or bad, it won't lie to you. 

Audio Research LS 27, Audio Research DS450 and Wilson Sophia.
Sounds absolutely incredible.
Thanks to all the bad press about class D, I was able to purchase the DS450 from another Audiophile that is chasing the dream. That system is never leaving my house.

I am a little worried that class D is what I am used to, and enjoy very much, but how do I get a larger sound stage?

Make sure to consider your room first. :) Your amp and speakers can’t overcome that.

However, you should listen to the M33 as well as some linear options, like Luxman or Ayre as well.

I have listened to a NAD M10 for over a year now and want to try to "improve" my system.  I tried the PASS INT-25.  Loved the huge sound stage, but felt like I was listening with earplugs in.  

I am a little worried that class D is what I am used to, and enjoy very much, but how do I get a larger sound stage? 

NAD M33? 

I just recently bit the bullet and ordered a Luxman 590AXII after listening to many different amps. I suppose that if you look hard you can find some poor sounding amps, but nothing I have heard across many typologies sounded bad. In fact, I am rather partial to some Bel Canto models. OTOH, the Luxman sounded sufficiently magical to my ears to spend more money than I should have and to sell off some other kit to pull off the deal. I was looking for a certain sound, not a certain amplifier type.

This is a very similar path to mine, but instead of Bel Cantos I was using ICEPower modules in custom cases.  I agree.  There was nothing wrong with my Class D amps, and a lot of linear amps did NOT best them at all. The Luxmans did and that's when I bought.  Again:  The Class D naysayers are prejudiced without cause.

Desk Top...😳 Uh, yeah..ok then 👍

Yeah, desktop, as in near field monitors. As in the most revealing place to put speakers. If you don’t hear Class D problems in near field you are not going to hear them in far field.  Desktop, as in: How many recording artists master their work.

Desk Top...😳  Uh, yeah..ok then 👍

looks like a cool little monitor.

Thanks @chicagoblue1977 !

I think if I attempted a similar build again though I might use a FaitalPro mid-woofer instead.  While I adore the transparency of the Peerless, it has a lot of limitations, including power, -3dB point and high frequency extension.  The Faital would be more versatile, and more compatible with tweeters that don't need to go so low.  On the desktop with a little bass or as surrounds they really are fun.

All I can say is that the OP must have gotten the good one. The 2 I had were nothing to write threads like this about.

I think you are misreading the intention of the thread. That the general complaints about Class D don't hold anymore.  Not that you would like the 3020D per se.  If any of the Class D bashers that float around Audiogon were correct then even the shop would not be possible for you. :) This is not a thread to convince you to buy a 3020D but to stop Class D bashing.

I will say that the character of the amp with speakers on my desk is one of pure air and seeing deep into the soundstage.

Best,
Erik

Everything I think I don't like sucks (even if I've never heard it).  The End.

NAD 3020 D???

All I can say is that the OP must have gotten the good one. The 2 I had were nothing to write threads like this about. The one I have left is doing shop duty. If it dies, it gets a cardboard coffin...

@jwl244, I have auditioned an NAD c298 which uses purifi tech. I had this powering a set of martin logan 60xti. I was using my naim uniti atom as a preamp. They sounded really really good. I tried doing side by side comparisons with the naim uniti itself powering the speakers. This isn’t a fair comparison as the atom is only 40 wpc. However, playing both at high (Not ear splitting) levels I was able to detect a subtle difference. I could be biased as I do love the naim sound. However, I found the NAD to be a bit too clinical in its presentation compared to the naim which was more lively and easy to listen to although not overly warm. The NAD was VERY clean but almost to a fault. I did use TIDAL. I do think class D is the future whereas class A and AB have kind of hit a wall as far as growth and expansion. Class D still has room to grow.

jwl244,
I’m familiar with the amp and the 60xtis. Two questions, did you try the c298 amp with any other speakers, and how many hours did you have on the amp before pulling it back out of the system you were listening to?

btw, I’m a Class A, A/AB amp owner, potentially looking for a smaller footprint type class-D amp to test with different speakers i design and build. I’m following experienced listeners trying amps with the newer Purifi modules. Wondering how far you took your listening sessions with this particular amp. Thanks in advance for added details you might be able to share.

Snapsc, hear...hear, I agree with you Tommy produces the best amps for my Magnepans and Martin Logans.  My first purchase was a used 4800A.  It was incredible good imho.  Next was a King Maraschino, used.  Then another King Maraschino direct from DAC, my last purchase was a King DTM.  They continue to be the best amps I've listened to.

I have 3 MTX Soundcraftsman S800 that the fan noise was too loud, for me.  I have 2 JBL Synthesis S800's and 2 Acurus 2003's.  They sit in another room gathering dust.  All of the above amps are rated at 200wpc, yet I do not listen that loud.  I listen to the music.  The DAC amps get out of the way, no annoying this or that.  

Tommy O'brien's amps are engineered by him, not pre made modules.  Erik give a DAC amp a try.  There has to be a reason they are hard to find on the used market.  My first good amp was the Acoustic Research Integrated back in 1973, then a Harmon Kardon Citation 12, many brands later, the DAC amps are my go to.  To me it is always which combination of speaker and amp pleases the ear of the beholder.

I have auditioned an NAD c298 which uses purifi tech. I had this powering a set of martin logan 60xti. I was using my naim uniti atom as a preamp. They sounded really really good. I tried doing side by side comparisons with the naim uniti itself powering the speakers. This isn't a fair comparison as the atom is only 40 wpc. However, playing both at high (Not ear splitting) levels I was able to detect a subtle difference. I could be biased as I do love the naim sound. However, I found the NAD to be a bit too clinical in its presentation compared to the naim which was more lively and easy to listen to although not overly warm. The NAD was VERY clean but almost to a fault. I did use TIDAL. I do think class D is the future whereas class A and AB have kind of hit a wall as far as growth and expansion. Class D still has room to grow. 

What about NAD’s m17 v2i. Anybody have this?

I live in the Caribbean and my main, bedroom and desktop systems are all class D.  Only my two Marantz AVRs are class AB.  I've never ventured into class A because it's simply too hot here. Air Conditioning is expensive, thanks to the exorbitant power costs.  As class D tech evolves I keep upgrading. I'm anxiously waiting on my latest; a Purifi amp that will replace a PeachTree IcePower based integrated.  

@erik_squires looks like a cool little monitor.

I have NAD 3030 on my patio/pavilion out by the pool. A/B Simaudio 340i in my main listening room and a pathos Classic One mk II in my office. Love them all and each has different qualities.

open you third eye.

I just recently bit the bullet and ordered a Luxman 590AXII after listening to many different amps. I suppose that if you look hard you can find some poor sounding amps, but nothing I have heard across many typologies sounded bad. In fact, I am rather partial to some Bel Canto models. OTOH, the Luxman sounded sufficiently magical to my ears to spend more money than I should have and to sell off some other kit to pull off the deal. I was looking for a certain sound, not a certain amplifier type. 

Ya like what ya like...

Hmmmm.....my NAD M33 gets great reviews with zero detectable distortion, but even more importantly, sounds great to me through my Monitor Audio Gold 100 speakers.  I’ve heard tubes, class a and class a/b, vinyl (yawn), nothing sounds “better” to me than my simple, streaming via Qobuz, small room setup.  Different, yes.  Better, no.

How many of you Class D haters really have Class A really expensive amplifiers.  The only reason I can think of to pay for expensive Class A amplifiers is to say you have one.  I’ve had Class A, Class A/B and Class D.  Class D with the right speakers is as good if not better than many Class A’s.  Each person hears differently, likes differently, so who’s to say what is best for you.  I currently have NAD Class D with Paradigm 3F Persona speakers.  To me and most who listen think the sound is great.  Buy what you like and like what you buy.  True Hi end Class A amp owners probably wouldn’t post on this site.

One more thing on the subject:  One trend that seems to be true often is that Pass owners buy very different speakers than I tend to listen to.  My electronics go very much in line with my speaker preferences.

It's hard to say what this is since I build my own, but top end Monitor Audio and Fritz are among my favorite commercial speakers.

If you really believe class d can’t sound good... there are a lot of cherryamp owners that have owned other amps and would disagree. 

As for one approach to the technology and how to extract good sound... this is an interesting read. 

https://positive-feedback.com/interviews/tommy-obrien-digital-amplifier-co/

Knowing you enjoy this sound, it is now understandable why you never liked Pass designs.

Well, I've been pretty vocal about what I do like instead:  Luxman, Ayre and Parasound, so the 3020 D alone shouldn't be a surprise to anyone.

Keep in mind, again, I’m not calling the 3020D the end all be all. I’d much rather listen to my Luxman all day long, but for a desktop system none of the stereotypes of Class D apply in my listening experience. I’m not at all unhappy with this. Of course the nearfield part of this also means I have different room acoustic issues, so I hear music differently at my desk than in my living room. The NAD 3020 D is good enough that I’m not rending my clothes and wearing sackcloth in despair.

I'm willing to accept your experience with this system of yours.

Why thank you.  The monitors are of course an unknown variable to anyone but me, but none of the criticisms levied against older Class D amps could be fixed by my speakers, or if they are, then damn, I designed some amazing speakers. :)

The impedance curve for them is also quite conventional.

I have to disagree, my AGD GaN amps are miles ahead of the older tech and design in sound SQ and i have heard all of the NAD products from the 33 down. You cannot even compare.

I am not saying the older Class D could not be bettered, but that the criticisms of it are overblown.

I have heard the specific NAD spoken of here, driving my modified and tweaked Klipsch Lascalas. Knowing you enjoy this sound, it is now understandable why you never liked Pass designs. As I have always said.....to each his / her own.

"...What makes them special in my mind is that they are true bookshelf speakers, designed with on-shelf or on-desk placement in mind thus they lack the bass bloat you’d experience with "normal" bookshelf speakers..."

Very cool. BTW: I'm willing to accept your experience with this system of yours. I'll put it into my memory bank for future use. 

You go Erik

The NAD, from my understanding is a hypex.

Nope. The 3020D uses an amplifier tech. which most so-called cognocenti don’t even know happened. It _was_ designed by Bruno Putzey but it is NOT the Hypex or nCore tech. It is a class A amp sandwiched between Class D rails. :) NAD refers to it as a "hybrid." I can confirm that for it’s rating, it idles unusually hot. My ICEPower amps at about 8x the power rating don’t get nearly this warm.

I’ve tried to grab people’s interest in the tech before but no one was interested. What do I have to do to get people to listen to me on this site?  :-D

Best,

E

teo’s opinions ARE a myth. 
He is entitled to whatever he likes.
Not creating bias.
We can like what we like knowing that his trolling is bogus.
+1 mapman for common sense

Calling them custom near field monitors kind of oversells them. :)

I made them in large part to write about the process of speaker design. You can find a lot of information here:

https://speakermakersjourney.blogspot.com/2016/02/the-lm-1-bookshelf-version.html

What makes them special in my mind is that they are true bookshelf speakers, designed with on-shelf or on-desk placement in mind thus they lack the bass bloat you’d experience with "normal" bookshelf speakers.

Myth is right.
two tee hee

Erik, Tell us about your custom nearfield monitors. 

Bashing class d is nonsense and does the basher’s credibility no favors. You either like it or not. Just like everything else. It’s that simple.  

I have to disagree, my AGD GaN amps are miles ahead of the older tech and design in sound SQ and i have heard all of the NAD products from the 33 down. You cannot even compare.

Little long in the tooth, mercy..

So it is a keeper Erik?

I have a pair of Wyred 4 Sound SX1000 (not the R) they were sure powerful with my planar combination. It took good cables to bring out the  luster so to speak.. They are ICE but the early version.  I was tinkering with the tone control for sure. The bass was a -2 and the treble a +1 or so. I haven't heard ANY of the newer Ice modules.

I been looking at the Purifi though.. It's sure getting a lot of good press and reviews.. A few bad ones.. I think that ONE was pretty predisposed to see Purifi in a LESS than neutral light.. Tough I suppose.. I never found it hard though.. Being honest with myself..

I'm my own worst critic. :-(, :-), :-l, :-0.

The NAD, from my understanding is a hypex.

<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>

From your understanding? So your blowing all the smoke about how something is engineered and you haven’t even listened to it?

If you haven’t used class Ds why on earth would you offer up a general opinion that seems to encompass ALL class Ds.

I’m getting ready to roll out the Mac and Cary valve unit and roll in class Ds Nord One Up for the summer. There are Krell class A, Threshold A/Bs, and a few others to chose from..

I’ll take the Class Ds over all of them just because of the heat index and the great sound quality.. They sound GREAT. Not perfect, not an A/B or class A amp.. BUT really really GOOD..

teo_audio you’re a broken record.. OR are they ALL (Records LPs) bad too?

It always get ME how people take a position AGAINST something that they’ve NOT had an experience with, BUT read or were told or have seen or FEEL, that class ds are just, bla bla bla...
(I like the song Bla, Bla, Bla though :-))

Grow UP! Ditto, Bucco, quit parroting what you HEAR and work on the principal of YOUR Own Due Diligence.

"Class D is still awful", from that point on I knew you didn’t have anything worth listening too. That is a SILLY statement.. Just SILLY..

If you don’t like the sound that’s fine.. Attacking a typology that has done nothing but get better and sell more and More and MORE.. How long has class D been around putting a serious DENT in amp manufacturing? A WHILE!!

That DOG don’t HUNT. Sales don’t lie..

Regards

I’ve heard it. Sorry, no go.

The NAD, from my understanding is a hypex. And that’s bog standard class D. If you seek a high quality low priced mediocrity and want to call it excellent.... then class D is your savior, your champion.

Sure, whatever you want.....

I’d be happy to be wrong about that (sort of, no one likes crow) but I’m afraid I’m not.

Anyway, you are just trying to start up some long convoluted circular thread. Again. Some gambit to get everyone to scratch each other's eyes out. Grow up.

Real shame I have a great sounding integrated sitting right in front of me that disproves your entire post. 

Further, I don't know where you get the idea that BASH or similar isn't being used. NAD's hybrid Class-D as well as the Yamaha EEEngine are derivatives.  Not sure which are licensed but similar ideas.  My ICEpower amps however, definitely not BASH, are the equal of mid-range linear amps, the better of some top end ClassA but awfully warm sounding.

Class D is still awful. The end. The damn things are built backwards. with the most important part of the signal being ignored and the least important exalted, in the measurements and the design.

That’s what happens when engineers with incomplete questions and data sets, go out and try and improve the qualities of said poorly informed question sets. They arrive at the wrong answer and a poor device regarding it’s intended solution point.

Digital is no less the same.

Steady research, sure..... but still the wrong question and answer set.

Another point is that class D in high end audio, may start to go away, as the BASH patent has expired as of last year. A dynamically variable power supply rail with a regular output device design (class AB, etc) is probably better, overall, re what part of the signal the ear works with. Class D makes a mess out of that all important small area. BASH, as a high efficiency design, harms it far less.

Class D would still exist as a widely disseminated type of device, due to it’s unique ability to fit smaller devices, reduced power levels, etc.. but BASH might come to dominate high end audio as the efficiency champ.. when played against Class D.

One might even claim, conspiratorially... that current or overall Class D design is an effort to get past the BASH patent. A poorly run effort, a compromised effort...with worse results.

IMO and IME, there is more unclaimed and unrealized high fidelity hiding in the BASH design than any current or known, or expected class D fundamentals in design. 

When BASH arrives in high end audio, then the walking back of Class D may take place. IMO, count on it. Meet the new king, etc.