[Russell Dawkins]

That EETimes article mentioned poor linearity/resolution down towards the noisefloor being a dealbreaker. Just what effective dynamic range do listeners expect?

I think we need 10-15 dB more both at the quiet and the loud ends than is generally realized. I think that truly adequate dynamic capabilities are the un-suspected "final frontier" and are the Achilles tendon in otherwise great playback systems, to wildly mix (or "wildly to mix") metaphors.

[Freo-1]

While Class D has progressed, do not concur they sound as good as a high end conventional amp.  As stated earlier, the more efficient the amp is, the more challenging it is to get the amp to sound its best.

In absolute sound quality terms, Class A (to me) designed properly will achieve a level of performance that is not matched by any other topology.  Yes, Class A is the least efficient, but does LESS to modify/modulate/switch the incoming signal than any other amp type. 

This article explains both pros and challenges with Class D:



http://www.irf.com/technical-info/appnotes/an-1071.pdf

[Russell Dawkins]

P.S., addressing the double glazing aspect, don't forget we are capable of hearing around 20dB "into the noise", thanks to our ear/brain's outstanding pattern recognition capabilities. Understanding quiet conversations in a noisy party is an example of this.

[doug s.]

I agree with Brian Cheney, fatigue has always set in with me listening to  switching amps. But put the same amp on a battery supply, and the fatigue totally disappears.

really?  i could have sworn brian said this:

"...Recently I had the W4S small integrated (100W/ch) in my system for several months, listening almost daily without fatigue or distress.  The sound was clear, natural, and well defined...."

i can understand how something else w/the same technology made brian physically ill - that has happened to me listening to xm...  it seems to me that, like anything else, implementation is key... 

doug s.,

keeping an open mind...

[doug s.]

While Class D has progressed, do not concur they sound as good as a high end conventional amp.  As stated earlier, the more efficient the amp is, the more challenging it is to get the amp to sound its best.

In absolute sound quality terms, Class A (to me) designed properly will achieve a level of performance that is not matched by any other topology.  Yes, Class A is the least efficient, but does LESS to modify/modulate/switch the incoming signal than any other amp type. 

This article explains both pros and challenges with Class D:

http://www.irf.com/technical-info/appnotes/an-1071.pdf

i am keeping an open mind.  the summary of the 7 year old article you reference was that class-d amps will provide "similar performance to conwentional class ab amps", if properly designed.  and that "constant innowations in semiconductor technology" are prowiding "better audio performance".  i am looking forward to hearing the latest-n-greatest that hypex class-d (like ncore) has to offer.  after all, 7 years has passed since the article was written.

i couldn't stand listening to cd's in any other than a casual manner before ~2000; now i enjoy them a lot, if still not as much as winyl.  progress is possible...

what i find really fascinating about the ncores is that raves have come from folks who need muscle amps, as well as from folks w/high efficiency speakers normally associated w/flea-power amps...

doug s.

[fredgarvin]

"what i find really fascinating about the ncores is that raves have come from folks who need muscle amps, as well as from folks w/high efficiency speakers normally associated w/flea-power amps..."

That's what I find a bit suspicious.

[doug s.]

"what i find really fascinating about the ncores is that raves have come from folks who need muscle amps, as well as from folks w/high efficiency speakers normally associated w/flea-power amps..."

That's what I find a bit suspicious.

ya, i am sure it's a plot, and everyone is making it up...   

presently, i have a pair of speakers that would love a muscle amp, as well as 99db efficient horns; when i finally get around to trying this technology, i will let ya know how they work on both.  but, do you think you can trust me?   

doug s.

[zybar]

"what i find really fascinating about the ncores is that raves have come from folks who need muscle amps, as well as from folks w/high efficiency speakers normally associated w/flea-power amps..."

That's what I find a bit suspicious.

The fact that an amp can work well in both instances is suspicious??  Really?

My current amps (Atma-Sphere MA-1's) work well in both instances.  In fact, many good amps (including the Ncore amps) can excel in either scenario.

George

[zybar]

While Class D has progressed, do not concur they sound as good as a high end conventional amp.  As stated earlier, the more efficient the amp is, the more challenging it is to get the amp to sound its best.

In absolute sound quality terms, Class A (to me) designed properly will achieve a level of performance that is not matched by any other topology.  Yes, Class A is the least efficient, but does LESS to modify/modulate/switch the incoming signal than any other amp type. 

This article explains both pros and challenges with Class D:



http://www.irf.com/technical-info/appnotes/an-1071.pdf

Freo-1,

How many times are you going to keep saying the same thing?     You are certainly entitled to your opinion, but must we be subjected to the same comments in post after post?

We know you prefer Class A amps.  We know that you don't believe that a Class D amps can't sound as good.  We know that you love to refer to articles written a long time ago to try and bolster your opinion.

How about something new or maybe just leave it alone?

George

[dflee]

Maybe cause he is trying to keep an open mind.

[JohnR]

Um, the paper referenced is an application note from a manufacturer of Class D amplifier chips, outlining some of the key technical issues.

[medium jim]

Frankly, everyone is basically saying the same thing over and over....

Jim

[rollo]

   I guess at the end of the day it is which Class "D" amp. Design and implentation of such is key to any design. Conventional, Hybrid ? Off the shelf modules or custom designed ? Switching power supply the heart of the design again off the shelf or custom desinged military grade ?
   Some get it right, some close and others no cigar. To offer general statements is not fair to those Manufactures who do get it right. Until one has tried every class "D" offering all is moot.
   As stated before I ran away from the early versions of class "D" heard in our system. Kept going back to my Class "A" SET. Not anymore. A hybrid design feed by a tubed preamp did it for our personal system.
   For us no more $2200/ pair 211 RCA tubes and other NOS tubes to sound right. No biasing, no trannie hum, 500W vs 18W, 128db vs 85db noise floor.
   One size does not fit all. Wether class "A" or "D" just give peace a chance. Try em.


charles
     
   

[fredgarvin]

The fact that an amp can work well in both instances is suspicious??  Really?

My current amps (Atma-Sphere MA-1's) work well in both instances.  In fact, many good amps (including the Ncore amps) can excel in either scenario.

George

When people make claimes such as that about a new product being introduced, 'it works great with all speakers in all applications' it sounds like hype and rouses my suspicion. That doesn't mean it can't be true. I guess your Atmos would be your example of that. But as to your question, yes really!

[WC]

Shouldn't we make a blanket statement saying that well implemented Class A, A/B, and D amplification sounds better than poorly implemented Class A, A/B, and D amplification and leave it at that. I just want an amplifier that sounds good to me. Who cares what Class of amplification it is.

[fredgarvin]

ya, i am sure it's a plot, and everyone is making it up...   

presently, i have a pair of speakers that would love a muscle amp, as well as 99db efficient horns; when i finally get around to trying this technology, i will let ya know how they work on both.  but, do you think you can trust me?   

doug s.

Heck no, I can't trust you. I don't just 'believe' personal opinions on the internet,  new products and flavor of the week are always full of hype. You know that, having been here from the start just like me. I find it amusing that some people get upset if their excitement about a component isn't shared by others.
 I do enjoy others reporting their findings about a product, it adds to the information and helps in making choices.

[fredgarvin]

Shouldn't we make a blanket statement saying that well implemented Class A, A/B, and D amplification sounds better than poorly implemented Class A, A/B, and D amplification and leave it at that. I just want an amplifier that sounds good to me. Who cares what Class of amplification it is.

I agree with that statement. But the topic thread is about class D vs others. 

[doug s.]

Heck no, I can't trust you. I don't just 'believe' personal opinions on the internet,  new products and flavor of the week are always full of hype. You know that, having been here from the start just like me. I find it amusing that some people get upset if their excitement about a component isn't shared by others.
 I do enjoy others reporting their findings about a product, it adds to the information and helps in making choices.

hey, i am not disagreeing regarding fotm and hype.  but, i certainly don't get suspicious when i read one report from someone w/108db-efficient horns who says an amp is the best he's heard, and then he buys it to replace his low-power amp, and then i read another report about the same amp, whose owner says it's the best he's heard, and he buys it to replace the muscle amps driving his 85db-efficient full-range floorstanders.  instead of suspicion, i get curious, and interested to further explore.

and yes, regarding these new ncore amps, i do trust everyone regarding what they say - as far as it working (or not) for them.  i am not so ignorant that i am conned by the "next greatest thing", and that i must have it simply because someone else said how great it is.  but suspicion?  for me, that happens when i suspect someone has some ulterior motive, and is not being truthful regarding what they are saying...  i haven't picked that up on my radar in what i have been reading regarding ncores...

ymmv,

doug s.

[*Scotty*]

Fred, Something to consider, every coin has two sides. If the Ncore is transparent and a truly closer approach to a straight wire with gain then someone will sooner or later feed garbage into it and be dismayed by the magnitude of the upstream problems that are revealed.
 
 Eventually we will hear about this. I am not suspicious of claims that the amplifier is suitable for both high and low efficiency speakers, a properly designed amplifier should be able to drive damn near any speaker without problems.
 
As far as a general discussion of the merits of Class D versus the rest, it is a waste of time. Pros and cons can only be meaningfully dealt with by considering specific cases. IMO
Scotty

[fredgarvin]

hey, i am not disagreeing regarding fotm and hype.  but, i certainly don't get suspicious when i read one report from someone w/108db-efficient horns who says an amp is the best he's heard, and then he buys it to replace his low-power amp, and then i read another report about the same amp, whose owner says it's the best he's heard, and he buys it to replace the muscle amps driving his 85db-efficient full-range floorstanders.  instead of suspicion, i get curious, and interested to further explore.

and yes, regarding these new ncore amps, i do trust everyone regarding what they say - as far as it working (or not) for them.  i am not so ignorant that i am conned by the "next greatest thing", and that i must have it simply because someone else said how great it is.  but suspicion?  for me, that happens when i suspect someone has some ulterior motive, and is not being truthful regarding what they are saying...  i haven't picked that up on my radar in what i have been reading regarding ncores...

ymmv,

doug s.

I guess you have a more dire definition of suspicion than I do, in this context.