What’s the big deal with class ‘D’ anyhow ?

This is an example of exactly what I am talking about:

"class-D has high levels of rising distortion at high frequency"

Quote from a.wayne. The above is just factually incorrect. While early class D designs do exhibit this trait, it is not present in current Hypex designs (Ncore) or in the latest from ICEPower (1200AS1 and 2). The data sheets with the distortion profiles are published for all to see, and you can find comparison curves for many Class A and A/B amplifiers at stereophile.com. Look for yourself. All the amplifiers have similar rising distortion as frequency rises, except most of the latest class D amps have lower distortion overall, including at high frequencies.

These are the kind of myths that lead people astray.
 
This is not the first time I was accused of making a decision based on a single listening session (of which I never do). Of course my observation is wrong because I didn’t yet hear the holy grail......But this hobby is no different than many others. The difference of opinion makes the world go round, and make this an interesting endeavor. I feel good when people love their gear. But because I don’t like it, should not make you angry. I also realize we all have different backgrounds and experiences. I have been following the same path for over 50 years. It is what makes me happy. If I reject a technology it has nothing to do with being old and/or outdated. I made more mistakes when I was younger. And if an amplifier weighs 100 or 1,000 lbs, it should not be considered bad for that reason.

Starting this thread was rewarding. I have gotten closer to an answer of the musical question; “What’s the big deal with class “D” anyhow ?”
 
@OP,
What is the purpose of your thread ? If we don't like a gear or a technology, we don't come in a forum and start bashing it. I think you are simply trolling and fueling an argument which has been repeatedly talked down in the forums.

Meanwhile, there is nothing wrong if you prefer the distortions of class a or a/b amps, others prefer much less of it :)
 
barrows said:
This is an example of exactly what I am talking about:

"class-D has high levels of rising distortion at high frequency"

Quote from a.wayne. The above is just factually incorrect. While early class D designs do exhibit this trait, it is not present in current Hypex designs (Ncore) or in the latest from ICEPower (1200AS1 and 2). The data sheets with the distortion profiles are published for all to see, and you can find comparison curves for many Class A and A/B amplifiers at stereophile.com. Look for yourself. All the amplifiers have similar rising distortion as frequency rises, except most of the latest class D amps have lower distortion overall, including at high frequencies.

These are the kind of myths that lead people astray.
Click to expand...

I gave you a fact and you respond with a myth , where's your graph disputing what i said , i can provide one showing poor Squarewave response and a steep curve , illustrating rising thd after center frequency ..

The output inductor is also a necessity in order to reduce high frequency oscillations, because you can't hear it doesn't mean others dont , cant see your irony thinking its old fashioned to like A/AB topology , but not ok for others to not like Class-D ..

...

Regards

All graphs courtesy of stereophile ... Class-D, PS Audio 700M


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Pass ....

Nelson designs are Low feedback vs class-D high feedback , if you look at type of distortion distribution and rate of change vs the class-D graph, tells me without listening both amps will have a completly different signature, look at the knee on the thd vs power graph ..

The squarewave difference is astonishing, audio being audio some will like one over the other , if level matching most will find the Pass warm sounding the class -D bright , the Class-D amp transitions more aggressively ...

Pass X 60.5 mi tinks ....

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OK, I do not have enough posts here to be able to post links or images yet. If you go to the Hypex website, and find the data sheet for the NC-500 OEM module, you will see all the relevant measurements, including distortion vs. frequency. Note that the distortion stays below .01% throughout the entire frequency range, even at 500 W into 4 ohms!

BTW, I never suggested that class A, A/B amplifiers sound bad (huh?) there are quite a few class A, A/B amps which I love.
 

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barrows said:
OK, I do not have enough posts here to be able to post links or images yet. If you go to the Hypex website, and find the data sheet for the NC-500 OEM module, you will see all the relevant measurements, including distortion vs. frequency. Note that the distortion stays below .01% throughout the entire frequency range, even at 500 W into 4 ohms!

BTW, I never suggested that class A, A/B amplifiers sound bad (huh?) there are quite a few class A, A/B amps which I love.
Click to expand...

Those measurements are not independently verified and Hypex wont answer nor indulge when questioned.. :)


there's alot to explain in those graphs i posted , its not just the amount but the shape, odd or even order content and percentage of change , which gives each their sonic signature, a signature you or I or anyone for that matter either loves or hate , as we all listen and accept these signatures differently...

I will later put up a couple more of each to explain my position a bit more clearly and no its not necessary to be super smart and deaf to like class-D nor old fashioned and stupid to like class a/ab , each has their own virtues and warts ....

Enjoy the music , we are all here for that ....


Regards
 
a.wayne said:
I will later put up a couple more of each to explain my position a bit more clearly and no its not necessary to be super smart and deaf to like class-D nor old fashioned and stupid to like class a/ab , each has their own virtues and warts ....
Click to expand...

Exactly and I respect your opinion :thumbsup:
 
a.wayne said:
I will later put up a couple more of each to explain my position a bit more clearly and no its not necessary to be super smart and deaf to like class-D nor old fashioned and stupid to like class a/ab , each has their own virtues and warts ....
Click to expand...
Mr Wayne, I have performed large scale blind listening tests of audiophiles who swore on class A etc...when their ears were actually hearing class D!! The key is that they had no idea they were listening to class D. I'm talking literally hundreds of people, including reviewers, "experts", etc.
The folks who claim "trust ears" listening reveals all. It does! :)
Now I'm not saying when folks know they are listening to class D that all sorts of melodrama can ensue. As they said in the Matrix, the mind makes it real.
However, if someone actually believes they can identify well designed class D like Hypex, vs class A or AB (SS, no high output impedance tube SFX processors), then I will be happy to oblige them with a controlled "trust ears" session, where they easily identify the classes.
Of course, I have one caveat, in that I will record the session to post on Youtube, for the entire world to see how golden ears can easily identify class D vs A/AB. None of this he said she said ether banter, but plain for whole world to see. The resolution of the camera will be sufficient to identify different shades of red when the results are revealed. All takers welcome. :)
 
The bottom line is what you hear. When I got back into this fun journey exploring amplifiers I did not bring a preconceived notion. Instead, since I was jumping back in, assuming a lot had changed I used my ears as the judge. From my list in an earlier post it can be seen that I tried a lot of different types of amplifiers, that I could afford. So I cannot make any comparisons to the extreme high end. I also listed my general feelings and reasoning why a particular amp did not become my long term solution.

In the final analysis the Class A First Watt I felt was something special, but the downsides were to great for it to be my long term solution. A lot of wasted power (low on my consideration list), very hot requiring ventilation considerations (a little higher on my list), but most important, just not enough power for long term with my new KEF.

The new mono PS Audio Class D have done it all for me. After having the W4S Class D early on, I felt Class D was probably not for me, but then with all the rave reviews on the new PS Audio I decided to give them a try. Sound wise just what I have been looking for, and all the upsides made this a fairly easy decision for me.

A friend has come over and listened to the S300 when I had it. He is a big tube guy. He said that it sounded excellent but he felt his personal adversity to Class D was probably clouding his judgement. He wants to come over the listen to the M700. He said after reading all the reviews he is going to try and not let Class D cloud his judgement towards these new mono amps.
 
AJ Soundfield said:
Mr Wayne, I have performed large scale blind listening tests of audiophiles who swore on class A etc...when their ears were actually hearing class D!! The key is that they had no idea they were listening to class D. I'm talking literally hundreds of people, including reviewers, "experts", etc.
The folks who claim "trust ears" listening reveals all. It does! :)
Now I'm not saying when folks know they are listening to class D that all sorts of melodrama can ensue. As they said in the Matrix, the mind makes it real.
However, if someone actually believes they can identify well designed class D like Hypex, vs class A or AB (SS, no high output impedance tube SFX processors), then I will be happy to oblige them with a controlled "trust ears" session, where they easily identify the classes.
Of course, I have one caveat, in that I will record the session to post on Youtube, for the entire world to see how golden ears can easily identify class D vs A/AB. None of this he said she said ether banter, but plain for whole world to see. The resolution of the camera will be sufficient to identify different shades of red when the results are revealed. All takers welcome. :)
Click to expand...

Can believe this there are dud class-a amps too ... :)

I did say this in my ramblings , we lock onto the sonic signature of what we like and or find negative about any topology genre ..


Regards
 
AJ Soundfield said:
However, if someone actually believes they can identify well designed class D like Hypex, vs class A or AB (SS, no high output impedance tube SFX processors), then I will be happy to oblige them with a controlled "trust ears" session, where they easily identify the classes.
Of course, I have one caveat, in that I will record the session to post on Youtube, for the entire world to see how golden ears can easily identify class D vs A/AB. None of this he said she said ether banter, but plain for whole world to see. The resolution of the camera will be sufficient to identify different shades of red when the results are revealed. All takers welcome.
Click to expand...

Set it up , very easy to identify IMO, i can pass thru anytime , I'm sure the Audio society can accommodate...


:)
 
Randy Myers said:
The bottom line is what you hear. When I got back into this fun journey exploring amplifiers I did not bring a preconceived notion. Instead, since I was jumping back in, assuming a lot had changed I used my ears as the judge. From my list in an earlier post it can be seen that I tried a lot of different types of amplifiers, that I could afford. So I cannot make any comparisons to the extreme high end. I also listed my general feelings and reasoning why a particular amp did not become my long term solution.

In the final analysis the Class A First Watt I felt was something special, but the downsides were to great for it to be my long term solution. A lot of wasted power (low on my consideration list), very hot requiring ventilation considerations (a little higher on my list), but most important, just not enough power for long term with my new KEF.

The new mono PS Audio Class D have done it all for me. After having the W4S Class D early on, I felt Class D was probably not for me, but then with all the rave reviews on the new PS Audio I decided to give them a try. Sound wise just what I have been looking for, and all the upsides made this a fairly easy decision for me.

A friend has come over and listened to the S300 when I had it. He is a big tube guy. He said that it sounded excellent but he felt his personal adversity to Class D was probably clouding his judgement. He wants to come over the listen to the M700. He said after reading all the reviews he is going to try and not let Class D cloud his judgement towards these new mono amps.
Click to expand...

This is not a challenge to your decision purchase Randy, just audiophool discussion , dont take it personal .... :)


BTW: You should use the same wattage class A/Ab to compare to your class-D ....
 
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