The Truth about Modern Class D


All my amps right now are Class D. ICEpower in the living room, and NAD D 3020 in the bedroom.

I’ve had several audiophiles come to my home and not one has ever said "Oh, that sounds like Class D."

Having said this, if I could afford them AND had the room, I’d be tempted to switch for a pair of Ayre monoblocks or Conrad Johnson Premiere 12s and very little else.

I’m not religious about Class D. They sound great for me, low power, easy to hide, but if a lot of cash and the need to upgrade ever hits me, I could be persuaded.

The point: Good modern Class D amps just sound like really good amplifiers, with the usual speaker/source matching issues.

You don’t have to go that route, but it’s time we shrugged off the myths and descriptions of Class D that come right out of the 1980’s.
erik_squires
Sorry Erik, but every Class D amp I have heard tells me they still aren’t ready for prime time.  Close, but no cigar.    I hear a brightness to the overall sound that many call “detailed”.  I do not like detailed sound, I prefer the lush romantic sound, think Mac.  What I don’t get is the price of some of the Class D amps, much fewer parts than a conventional class a/ b amp yet they  cost as much if not more.  

With that being said, I do prefer the sound of the Hypex modules over the Ice slightly, but that is just my opinion.  I am basing my observations on the Merril monoblocks, the wyred4Sound amps and a few others I really cant remember. 
@stereo5 Then consider me one of the lucky one’s.

Sighted or blind, I cannot hear a difference between them an Parasound A23s. None. Zero. Nada.

So, since it is my wallet and tastes that pay those bills, I’d rather go with the more energy efficient one.

And in fact I prefer the sound far over and above the sound of Pass. Same for Parasound vs. Pass. :)

But it isn’t because of anything I can hear as "class D sound."

You don't have to like a particular amp, but I think being dismissive of them as a class is short sighted. 
You don’t have to go that route, but it’s time we shrugged off the myths and descriptions of Class D that come right out of the 1980’s.
Make that 1990s....

First of all, I was giving my opinion and experiences with Class D and found it’s not for me, period.  I am ecstatic with my McIntosh amp, pre and integrated and they are the keepers for me.  As far as being short sited, since I am not considering any more purchases, it really does not matter.  I have heard 5 or 6 different Class D amps and have not liked any of them, so why would I continue to seek them out?   Perhaps you should of mentioned in your original post not to comment if you aren’t a fan of Class D, then I wouldn’t have bothered.  Sorry I burst your bubble.  
There are listeners who like Eric will hear no difference between class D and non class D amplifiers.   Other listeners such as stereo5 can and do hear distinct differences. Both groups are valid.
Charles 

The "truth" about class D is that it is all over the place.......just like all the other classes. They all have strengths and weaknesses......and all classes have gotten better with time. Every single thing you do to an amp module or wiring or casing or whatever makes a sonic difference. Every amp using the same stock module will even sound different as different wires, solder, connectors, damping, feet, etc. are used.

The latest and best? Class D (the Merrilll $36,000 Element 118 and the $8000 Nuprime Evolution 1) may have sound that will compete with anything. All amps based on OEM modules (modified on not) are probably not as good as these. The brand new 12000AS1/2 modules from Icepower (brand new ICEedge technology) are really refined and low distortion and tweaked out can give some serious sound and high power (600 watts into 8) for little money. I will have a $1000 amp out soon with the stereo module and also a dual mono stereo unit for $1900, as well. I expect these will beat all the older Hypex modules but will not be as good as these latest expensive tweako things mentioned above.

Everything keeps getting better. If you have not heard a class D amp for awhile, you might want to check out the very latest offerings. I will be selling my amps with a 30 days in house money back audition period and also will have one of each my amps out on tour. I have been tweaking audio since the late 70s and these amps will have 40 years of listening tweaking in their design. This is way more than a stock module in a box....way more!

@ricevs says.....

“The "truth" about class D is that it is all over the place.......just like all the other classes.”

Perfectly stated as the universe of Class D or any class of amps is far too big for over generalizations to apply. Experience has shown me that tube amp sound is all over the board as well as Class A/B etc...
The power supply employed in a Class D design can all by itself dramatically change the sound. So many other aspects can change the sound of a Class D amp such as design, build and parts quality differences.

We should also throw in pure digital powered dacs as they offer tremendous sound quality with the added option of room correction and SOTA volume control. We have so many great choices today.  


We should also throw in pure digital powered dacs
Just to be clear: all forms of class D are analog devices. I know, switching this, digital input that and on and on but class D is still analog. Just so there's no confusion :)
I’ve had my Class D Cherry Amplifiers for a yr now and I’m extremely happy. I don’t ’hear’ anything that sounds like a bad-purchase, and I listen Friday / Saturday nights from like 8P to 2 or 3AM. Will I trade them some day? Probably, like I trade cars. But I do believe Class D’s time has not just ’come’ but is here to stay. My Cherries were preceded by a First Watt J2 which was preceded by a Yamamoto A-08S which was preceded by a long list of amps. For reference, my system to-date is as follows PS Audio DirectStream Memory Transport> PS Audio DirectStream DAC > Cherry Amp DTM 60V > Reference 3A MM de Capo BE.
I have built some mono amps from Abletec modules.  They were actually quite good.  I don't know if they were "World Class" or not, but you know what, they played music and they sounded like music.  I did sell them, but not because I didn't like them.  I simply had an old Audiophile buddy that had his amp go down beg to get them from me.  
@timlub 

Parts Express is now selling ICEpower modules directly and for cheap. :) 

Best,

E
I've heard about five different versions of Class D over the last few years and they all disappointed in one key area - naturalness.  There was always something artificial sounding that never let me engage with the music.  In all honesty, the Pioneer SC series receivers impressed me with their presentation.  It was still a receiver, but I found their amp sections to be almost unparalleled in that application.

I haven't given up on the technology yet regardless of the above.  I understand it might simply come down to finding the right specimen to hook me.
Grannyring+1. I have the Nuprime Reference 20 monos modded and compared the other half dozen class D that I have heard and many conventional amps, they are up there with the best. Liquid, natural, transparent, killer bass, and zero edginess, tizzy, or glassey,
There are many excellent Class D amps out there. To say good class D is bright means you are not very well versed in quality class D. I have the Danish built Gato 400S  which has a Very natural character musical with nice image depth.
Mark Levinson, Jeff Roland , And a bunch of others have custom. 
Built  Analog input as well as output stages. These amps are all
in the $6k or better range . Their distortion is far lower ,run cooler 
and no where as heavy . Unless you have heard the best digital 
from at least 4 Tom name brands then you can’t speak with any 
valid experience . As all Audiophilesit is just your opinion.
these Class -A rated amps or preamps have arrived .research 
digital has indeed arrived including recordings  when done properly.
@erik_squires 

Thanks Erik,  I wouldn't mind it.... Over time here on Agon,  I've contributed a ton on the speaker side. That's where all my experience is.  I've always known that amps & pre's have been my weakness.  I've been studying circuit design and have recently purchased a few old amps that I am actually rebuilding from top to bottom.  So, I'm staying with these oldies but goodies for now. 
Hey... I can understand... how you folks can blather on about class A, tube amps, and all manner of BS, but... until you've heard a Class D Audio amp (the brand), you haven't any basis for a judgment.  

Tom builds simply outstanding class d amps, that will challenge any class A, or tube amp out there.  
My Red Dragon mono-blocks sounded every bit as good as my Krell..I'm kind of glad they get a bad rap because otherwise they wouldn't be so cheap...
@atmasphere  

I was talking about units such as the Lyngdorf 2170.....

“The TDAI-2170 is 100% digital, without sound-deteriorating digital-to-analog conversions. The digital signal drives the speakers directly, with no translation and no middleman.” 

It takes a digital signal and amplifies it without a conventional dac.  The signal remains completely digital right to very point where the signal is fed to the outputs....only at this point does the signal convert to analog. This unit is not a Class D amp. 


audiothesis - It would help if we had your point of reference. What do you consider the most natural amplifiers you have heard? 

If you want them to sound like a boutique OTL amp, chances are they never will. :) 

Best,

E
..and that’s just it Erik. I am a single ended fanatic. With solid state I find I usually prefer a good A/B over even class A amplifiers for some reason.

There are always exceptions that might tickle your fancy in a different way and that’s what I hold out for. I’ve found exceptions in most categories now, just not in Class D. The units I’ve heard (rather not mention) were bountiful in the bass but presented artificially. There were other artifacts throughout the spectrum but the bass stood out the most to me. The units I tried were not world-class but not trash either.

Maybe natural was the wrong word and organic fits better. It all felt too etched to me, like overdoing the sharpness on a television.

Mola Mola was on my short list to try and I recently had another one recommended to me (by another single ended fan at that), though the name escapes me at this point.  I definitely am not closed-minded to them - just waiting for the right one.
To say class D is bright means you are not very well versed in quality class D.

This is correct as they can be either too bright (hard) or to opaque (soft) or a milder mix of both, and it nearly always comes down to how savage the output filter is that attenuates the switching frequency. As it's phase shift effects can be measure within the audio bands upper frequencies right down to 5khz, especially, the "opaque sounding one". You never hear of anyone criticizing the bass, that's because it good!

There are those that for the life of them can't hear anything wrong, good luck to them I say.

Cheers George
audiothesis : 

Aha! :) 

I knew you were one of those OTL scoundrels! 

J/k : But the truth is if OTL is what you like, then talking about good Class D amps is not going to be your cup of tea.

Best,

E
I'm new to digital music, but not analog.  I have a vintage McIntosh system that's been my main system for almost 20 years.

I started building a listening room digital system about 4 months ago.  I'm mostly-retired and didn't want to spend too much on it.  I got a good deal on a new NAD M12/M22 v2 combo, a used pair of Tannoy 8 dcti speakers; and a demo Innous Zenith MK2.  

At first, I was not very happy with my new purchases.  As the equipment has aged and I've bought better speaker wire, interconnects, and power cords, I've experienced a dramatic improvement in SQ - but at times, the highs are still too bright.  I plan to treat my room within the next 30 days, hoping that will help enough.  If not, I'll have some decisions to make.
Old school, get professional help from GIK,

and don't neglect the flooring, between and behind the speakers. Try using pillows and blankets to test with for free.  :) 

Best,

Erik
Good modern Class D amps just sound like really good amplifiers

@erik_squires   I completely agree with you.  Just picked up a Wyred4Sound STI-v2 today, replacing a Parasound HINT (which I really loved)

I'm so impressed with W4S out of the box.  It's very similar sounding to the Parasound, but better dynamics, and quieter.  Still has a very lush, and warm sound.

I expect it to improve more as I run it through the long weekend.

It's fun isn't it, watching the hobby change?

It makes me wonder how long it will take for the modern world to be accepted by HEA. And, will this mean more folks will be entering HEA only from a different point of reference. The days of expensive HEA are numbered as we are seeing, but more exciting, the replacement has been getting refined for some time now.

Look for speakers to change too.

Michael Green

http://www.michaelgreenaudio.net/

I'll take Ralph's tube amps any day, not those 3D printed things.
'It's tubes stupid'.
Or as Vladimir of Lamm said in an interview - You can get killer bass out of transistors but that's not how it sounds in reality. He himself makes hybrid power amps, though, in addition to tube amps. Oops..

Bought the Rowland 501 monos when they first came out and have had absolutely no regrets. Class D is just a technology which can be used or misused. Really unfair to relegate it to some inferior status or to make generalizations. Tubes versus solid state is another example of either one sounding superior to the other being subject to the quality of design and the price range. Like they say 'it all just depends'.
Straight from the horse's mouth:

S&V: Generally speaking, what are the key benefits of Class D versus the traditional Class AB and Class A designs that have long been favored by audiophiles?
BP: Efficiency and therefore the ability to construct amps that are powerful for their size. Only that. Modern Class D amps, in particular mine—ahem—sound good not because they’re Class D, but in spite of it.
Read more at https://www.soundandvision.com/content/bruno-putzeys-head-class-d#61cL4a1ATw0DkUL2.99

Opinions vary.

I power my studios Avalon Acoustic Monitors with Hypex nCore 400s and my listening rooms Avalon Acoustics Eidolons with Bob Carver Tubes.

When using the switching amps to drive the Eidolons the subtle difference in presentation becomes obvious to us. We find we listen for much longer periods of time with the tubes. Relaxing is the word that best describs the difference.

The switching amps slightly more forward and plate glass transparency that many may describe as brightness has become religiously indispensable in the acoustically treated studio.

Pitting Class D against linear solid state or tube amplifiers is silly. They're simply another class of amplifier to choose from, that's a truth. I'm not going to drive my subwoofers with tubes nor am I going to use the studio for my listening room.   
helomechStraight from the horse’s mouth:

We had better quote some noted designers as well.

Bob Carver
"I built many of them right here in my own laboratory with the thought they could and would fulfill that final promise.... I was never able to build a Class D amplifier that sounded as good as a linear one."

John Curl (Parasound, CTC, Vendetta Research, Constellation)
"Some version of hybrid Class A/D looks like the future in optimum audio design."

Cyrill Hammer (Souloution)
"if you want to have your product performing at the cutting edge it is not possible with today’s known switching technologies. In order to come close to the performance of the best linear design we would need high-current semiconductors that provide switching frequencies of several MHz or even GHz."

Lew Johnson (Conrad Johnson)
"I tend to think that Class D circuit design is an approach best relegated to producing low-cost, physically manageable multichannel amplifiers where one might accept some compromise in sound quality for the sake of squeezing five, six, or seven 100 watt channels into one moderate-sized package for a budget home-theater installation."

Vladimir Shushurin (Lamm)
"No, it is not. And I would like to respond to the second part of this question with an allegory. Any field of human activity defines a number of requirements which, when properly implemented, guarantee a positive outcome.
For example, the basic requirement in the army and sports is an able-bodied individual. So, it would be quite natural to concentrate on searching for such an individual (especially as we know where to find him).
However, out of the blue we decide to choose a feeble-bodied person who, on top of that, is encumbered by various diseases. Having made this decision (which is a priori improper) we start justifying it to ourselves and others by citing the great state of our medicine, which is capable of curing many ailments."

Fumio Ohashi (BAlabo)
"No. Class D can’t really be considered for super-high-end performance in its present stage of development, although it can be fine for mid-market products."

Nelson Pass (Threshold, Passlabs)
"Does a $10 bottle of wine compete with a $100 bottle? Of course it does, and it often wins based on price. Right at the moment Class D designers seem to be still focusing on the objectively measured performance of their amplifiers. I expect that at some point the economics of the marketplace will encourage them to pay more attention to the subjective qualities, and then they will probably play a greater role in the high end."

JÃrgen Reiss (MBL)

"I have worked a lot lately with Class D. Ninety-nine percent of Class D circuits are not competitive with linear circuits.
Most Class D sounds sterile. Its tricky to figure out what to do to compensate for that."

Jeff Rowland
"I consider Class D to be highly competitive in the present, and to offer an evolutionary pathway of audio design that may produce even more astonishing results in the future."

Thorsten Loesch

I have yet to hear a pure class D Amp I’d rate above "below average for solid state" (which is not very high performance).
In a little update of my classic "Valve Analogue Stages for DAC’s #" I wrote:
"Perhaps more crucially, so called Class D Amplifiers, which have in recent times sprouted up like mushrooms after a warm rain, continue to use the straight two or three level modulation scheme described above. And thus they still require the use of heavy handed noise shaping to attain anything like acceptable 16 Bit Audio performance.
The clock frequencies for these amplifiers are usually at 300 KHz to 1MHz in the best cases. That is 3,000 to 10,000 times lower than what is required to attain 16 Bit / 44.1 KHz performance without noise shaping and other forms of signal manipulation!
And again, one is baffled and perplexed by the rave reviews many Class D amplifiers receive, as baffled as one was about the late 90’s reviews of timeslicing dac’s. The best of breed I have auditioned were certainly not bad; however in direct comparison to the best available valve and solid state amplifiers they do not produce a very good sound. Well, at least they offer novelty and the reviewers something to write about other than another (however good sounding) 8 Watt valve amp.
Incidentally, the best sounding Class D amps tend to be really low power single chip devices (putting out little more than the 8 watt valve amps), presumably because they are faster AND because they always work near what one might call “full scaleâ€, if they would be dac’s. On second thought, they of COURSE are DA Converters and where a Class D amplifier accepts analogue input directly it is an A2D converter followed by a power D2A converter!
What an insight!?"
Mark Levinsons interleaving of multiple Class D Amplifiers is potentially a step in the right direction, but does not go far enough.
Personally I think that the best option would be something that combines a Class D Amplifier for the heavy lifting with something Class A for fine detail. Probably implemented in the style I did for AMR’s AM-77 "Jikoda$" Style. In this case both of the circuits involved can operate fully open loop.
In many ways the problems in Class D Amplifiers are analogous (but not identical to) those in Class B Amplifiers (but without an option to implement Class AB or Class A) so similar solutions apply.

Thorsten Loesch
All Class D amplifiers are essentially delta-sigma DAC’s.
If the input is not digital PWM signals (aka "DSD") but analogue audio then it is also a Delta Sigma Analogue to digital converter...
Now DSD (aka SACD) which to my ears fails to come close, never mind equal true PCM CD Replay in most aspects of sound quality, operates at 2.8MHz switching, or around 10 times as fast as common Class D Amplifiers...
Why anyone would want to listen through an A2D followed by an D2A Converter that are around 10 times worse than single speed DSD is beyond me.
But with enough hype and snazzy naming it cannot help but sell high and wide.


Cheers George
Cyrill Hammer (Souloution)
"if you want to have your product performing at the cutting edge it is not possible with today’s known switching technologies. In order to come close to the performance of the best linear design we would need high-current semiconductors that provide switching frequencies of several MHz or even GHz."

This is the one, that I believe hits the nail on the head, and why to some that hear it Class-D sound in the upper ranges hasn’t come of age yet.

Only Technics with their unobtainable $30k SE-R1 comes close with a 1.5mHz switching frequency instead of what all the other are using today 400-600kHz. But as Cyrill Hammer states it should be even higher.

Cheers George
Somebody who really knows a lot about class D, Bruno Putzeys, designer of Hypex, Mola Mola and Kii, talking about the subject:

https://www.soundandvision.com/content/bruno-putzeys-head-class-d

We know somebody who moved away from a Soulution 710 to Mola Mola Kaluga’s. And consider they are one fifth of the cost. They drive difficult loads with ease, are very natural sounding on live recordings for example, they have a very natural deep and controlled bass and loads of power. They are also compact and don’t consume much electricity. The more you improve mains quality with better power cables, connectors, dedicated mains, balanced power, mains calming devices, the more these amps shine. In my opinion they are one of the finest amplifiers available today regardless of cost.
Mola Mola Kalunga is a Belgian-Dutch product,Made and designed in Belgium. They worked together with the University of Leuven and Brussels. Greath stuff !!! And put them on one of the world’s best speakers: “Ilumnia magister” (Belgium). And you are in the clouds...
most of the Class D amplifiers (Devialet,...), you can find them on é-bay or 2-hands, there is a reason for. For me is Class A,AB, still the best. And bass must sound natural,not “boom,boom”,otherwise, it displaces the other Instruments and holographic listening is excluded.
No quote by Flemming Rasmussen of Gryphon, though I am sure he has made quite a few remarks.
I have to concur with Erik - I currently use Wyred 4 Sound SX-1000R monos (upgraded fuses) & they sound great.
I used to have GamuT M250i monos & I don't miss them.
I have owned PS Audio GCC 250w amp since new (still in my TV system), several W4S amps; mono & multi-channel, Emerald Physics 100.2SE monos (much better with special fuses, but still bright). I was about to pull the trigger on a Nord Two (newest Ice tech) when I got a great deal on a Audio Alchemy Stereo amp, and a month later I replaced my Hattor XLR (impedance mismatch) with a AA Dac/Pre. The combination is revelatory. Don't believe me? Search The Absolute Sound March 2016 review. That COMBINATION  produces a natural sound that defies its price point : The combination MSRP is a mere $4000, including a kickass dac
The gamut M250i monos are greath! My friend have those. These are forever.
off course Gryphon is very good! (Diablo)
@georgehif - You should start your own magazine, because even though you don't like Class D you are in every single discussion about it. Call it: 

"Why I can't move past 30 year old arguments." 

Best,

E
erik_squires
Old school, get professional help from GIK

and don't neglect the flooring, between and behind the speakers. Try using pillows and blankets to test with for free. :)
Erik, thanks much for the advice.  I have throw rugs, over a tile floor, in front of the speakers.  I'm going to try pillow and blankets today!  I saw another suggestion on agon about hanging towels behind the speaker as a test.  I've got plenty of towels and nothing to loose.

The dealer who sold me the Zenith came to my house with an assortment of demo diffusers, absorbers, and bass traps.  I could have purchased them at a good price, but the colors did not fit my taste or room, and some panels looked worn.  But, I will say, the SQ improved with them.  

I'm educating myself on DIY acoustic treatment and have been corresponding with RealTraps.  This past week, I began researching GIK products.  I plan to call GIK after the holidays, send pictures of my setup, and go from there. 

Regarding Class D amps, the NAD M22 v2 uses Hypex nCore technology; and overall I'm quite happy with M12/M22 combo//Zenith MK2.  The sound and SQ is different than that produced by my 90's era McIntosh C31v pre and MC2600 PA; and my 80's era SoundCraftsman SP4001 EQ/pre and Pioneer SPEC-4 PA.  Since the source material, technologies, and speakers are different with each setup, I think that should be expected.  I use each system different.  My vintage analog gear is in a rather large basement bar/sitting/pool room area; the digital gear in my basement listening room. 

If I can warm the listening room sound a bit and reduce the echo chamber effect with the right room treatment (and may different cables, cords, and interconnects), I'll be a happier camper.

About a 18 months ago I got my first class-d amp from Nuprime. They use a proprietary module. 

The price/performance ratio is outstanding with my IDA-16. Completly happy with every aspect of its performance.

Cheers,

Scott
I would like to explain to everyone why heavier than air flight is impossible, you cannot transmit radio signals across a vacuum and transistors will never be useful. Bear with me as I gather the relevant quotes.
Post removed 
Haven't read everyone else's posts, no time. 

Every time I use a class D, then switch back to class A/B I think, nope, class D is not quite there yet. Case in point, the superb Belles ARIA Mono Block Amplifiers I reviewed for Dagogo.com outshine the class D amps I have used (several). The ARIA amps are still here, the others are gone. 

That's not to say you cannot build a wonderful sounding rig with class D, as I have done so many times. But, you get even a more affordable classic design such as the ARIA set up well and imo there is still a significant gap in performance. I suspect you would have to spend at least double the amount of the ARIA amps to get close. 

I have been through this cycle several times, perhaps five or six times, and while class D keeps getting better, so do the class A and A/B amps. They are not sitting on their laurels, but making nice improvements, refinements as well. 

FYI, the just reviewed COS D1 DAC + Preamplifier (reviewed) is an impressive unit, and with the ARIA Monos the sound quality is most impressive. I have used some very pricey amps, and this combo is the best of class with the Vapor Audio Joule White. Of course, I am using the Schroeder Method of Interconnect Placement with it (see other threads under Cable forum if interested). This gives a very unfair advantage over a standard setup. At this point it is not recommended to use the Schroeder Method with class D amps, as it could cause problems operationally. (NOTIFICATION; ANYONE CONSIDERING THE SCHROEDER METHOD OF INTERCONNECT PLACEMENT PLEASE HEED WARNINGS/RECOMMENDATIONS IN REGARD TO USE OF THAT METHOD; it is entirely a "do at your own risk" activity). Consequently it's no contest between class D and class A or A/B. The Schroeder Method causes the traditional setup with a class D amp to sound significantly lacking in comparison to a class A or A/B with the Schroeder Method. It is so superior that I have reservations that any class D set up with a single IC would outperform it regardless of cost. That suspicion may be proven wrong over time, and I will keep trying various class D amps (So far, the Pascal based Red Dragon has been a standout; I would never try the Schroeder Method of interconnect placement with such an amp), but I suspect the deficit of a single IC is too great to overcome. 

Make no mistake, the Schroeder Method is no gimmick, nor a "tweak". It's quite powerful in its effect, with an impact similar to upgrading one or two components to the tune of several thousand dollars. I am not exaggerating. Read the comments from those who have tried. But again, check with your manufacturer of gear and it's entirely do at your own risk. If you think cables can't do such things, then you are a bit behind the curve on cables.  And, no, I have zero interest in arguing that point. :) 

So, at this point, merely doubling interconnects as per the Schroeder Method has now handily bested any class D amp set up with single IC that I have ever used, and in the foreseeable future. 
I have no time to read your comments, but to show my respect I am going to paste a long lecture here on what I think on the subject.

The Squires method is superior in every way to any previous method. In terms of refinement and air and presence, the Squires method just cannot be compared to any other method.

It has on occasion caused premature births however and needs to be used with caution. Also lights in your room may shift slightly red, undetectable to most. If you aren’t paying attention you will absolutely miss it.


<< rolls his eyes >>
Post removed 
Post removed 
because even though you don’t like Class D you are in every single discussion about it.
Sorry didn’t know it was a closed shop, and only one sided opinions were allowed!

"Why I can’t move past 30 year old arguments."
Because they still apply today, but there’s light on the horizon. Just because you can’t hear the problems, doesn’t mean others can’t. As posted here already by others to your chagrin. 
So, to sum it up,   Class D - you either like it or you don't.  No middle ground here.