Audiophiles, generally don't like class D amps!

[fpitas]

If I am not wrong about dampening factor, Hegels and Rotels go up to insane 1000, so how exactly does that explain that D class is perceived as lean?

And as has been pointed out elsewhere: your typical passive speaker has an inductor in series with the woofer. It has a DCR of a few tenths of an ohm. There goes your damping factor!

 

[mocenigo]

Understood, but I don't see any relation to my following statement from #71 that you have quoted:

Nothing, they are orthogonal if we exclude audio subjectivity but admit any other senses (including the haptic feel of some at of processing the metallic surfaces of electronic equipment, to make an example)

 

[GXAlan]

One thing I have wondered is why there aren't more direct digital class D amps. After all PWM is a form of digital. Why take a signal, convert it to analog and then back to PWM.

The Sony S-Master HX does that but in the absence of negative feedback, it doesn’t measure great. People like the sound signature though, so it may very well be like a solid state tube sound.

 

[Gorgonzola]

What they don't like is the price is to low for the given specs, also the size and weight is to low. They also don't like you can't pay for increased perfomance up to infinity. Some people thinks better performance always follows increasment of the price.

Yes, it's almost weird. A friend of mine responded to a post on the audiophile forum previously alluded to. His suggestion for high performance but low cost amp was completely ignored, while there well lots of suggestions for pricey amps of the likes of Pass' First Watt.

The OP there asked for suggestions for the "most detailed, quietest low-power SS amp for horns". My friend suggested the Topping LA90 and was completely ignored, while there were plenty of comments regarding $5k suggestions.

 

[Overseas]

Yes, it's almost weird. A friend of mine responded to a post on the audiophile forum previously alluded to. His suggestion for high performance but low cost amp was completely ignored, while there well lots of suggestions for pricey amps of the likes of Pass' First Watt.

The OP there asked for suggestions for the "most detailed, quietest low-power SS amp for horns". My friend suggested the Topping LA90 and was completely ignored, while there were plenty of comments regarding $5k suggestions.

Because in my local market the Rotel RB 1552 mkii is cheaper than LA90, for ex. And more powerful.

 

[audiofooled]

When certain audiophiles of sorts change a component in their system, they "listen" to that component, be it a cable, riser, isolation pad or in this case power amplifier. Which IMHO is completely wrong on so many levels. And then they assign certain "attributes" to what they hear. Important thing is that loudspeakers in most of these cases remain the same, maybe they are moved slightly, how they sit at MLP is changed a bit, ambient noise can also vary, etc. Sometimes they go to their friends to listen to their setup and they draw a conclusion that they are "listening" to the actual amplifier, even though loudspeakers and setup is totally different. So, a controlled blind test is rarely a method. Also, there are reviewers...

I stumbled upon this. Make of it what you will, because I can't. Anyway I thought I'd share because he mentioned Jeff Rowland stuff we saw earlier in the thread and said some general things about class D that are less appealing to audiophiles and could be just on topic of the thread. Video is long but he talks slowly so you can speed it up a bit:

 

[Schollaudio]

Why do "some folks" here assume vintage and audiophile gear sounds gooey sugary or bad in general? Or that older solid state gear isn't as good as modern classD?

Still one of my best audio experiences is with a system built in the 1930s.

Look at the Apt Holman review.

It would be great to see more 1980 Japanese receivers and amps reviewed or even more very expensive gear. Also some well made prosound gear. If shipping wasn't so expensive I ship some amps for testing. Is anyone testing in PA, NJ, Maryland area?

I've been using class D for years and the unit I like best has a poor SINAD. It kicks ass doing everything well. So that isn't the end all and be all of sonic determination. That said, my Ashly and Chevin amps stomp all of them all around.

If anyone in south central PA wants to spend a nice afternoon doing amp shoot outs give me a PM.

 

[Waxx]

It's very often someone in the internet says "they are wrong by definition". And also they in general don't look fancy and expensive enough, even the top level builds that are for sale. But the same kind of fundamentalism is here also present, the only thing is, it's more based on science and not on some audiophoolery. But some don't get that scienctific superior amps can sound less good than less scientific superior amps in the subjective side of things... All fundamentalism is wrong for me.

But for me, it's whatever fits me. And i have all kind of amps, tubes, transistor (class A and AB) and classs D. And i use them depending on the speaker and the goal. The amp i now listening to at the moment is a tube amp driving some fullrange drivers in reflex cabinets. And even if they don't measure that good, l like the sound a lot. And that is what matter for me. But i will never claim those are more "true to the source" than some well designed studio monitors with dsp and class D amps, they are not.

And if you don't like, it, I don't give a .... And you shouldn't neigher!

 

[mocenigo]

The Sony S-Master HX does that but in the absence of negative feedback, it doesn’t measure great. People like the sound signature though, so it may very well be like a solid state tube sound.

It’s the distortion. Audiophiles like it because they believe they can hear “more detail” with that equipment. Of course they do, but it’s information that was never in the recording to start with.

 

[Mart68]

Yes, it's almost weird. A friend of mine responded to a post on the audiophile forum previously alluded to. His suggestion for high performance but low cost amp was completely ignored, while there well lots of suggestions for pricey amps of the likes of Pass' First Watt.

The OP there asked for suggestions for the "most detailed, quietest low-power SS amp for horns". My friend suggested the Topping LA90 and was completely ignored, while there were plenty of comments regarding $5k suggestions.

If someone rejects measurements as irrelevant then they don't really have any metric to work by other than price, and what the Darkos and Guttenbergs have to say (and they are also basing their opinions at least partly on price).

This is why you see a lot of advice along the lines of 'You will really need to move up to the £4K to £5K bracket to get a meaningful improvement.'

 

[TimF]

This is off topic, and I know it is sick and crazy, but I want to share it because it is so satisfying. It is a satisfying as a good layout on a class D amp board. In the video don't uou just love how she puts the little nut on the little bolt with a rubbery yellow q-tip kind of tool. Such nice and reassuring connectors, too.

 

[Ricardus]

What do you mean by D and A ?

Check what this thread is about.

 

[mhardy6647]

If someone rejects measurements as irrelevant then they don't really have any metric to work by other than price

... don't forget the ever-popular weight!

there is a (perhaps apocryphal) story of a commercial amp manufacturer -- a pretty darned respectable company -- which added a piece of steel (?) plate to a one of their amplifier models some years back, apparently to give it heft commensurate to (or is that with?) its price.

 

[Ruffy]

I had a bloke at a hifi store tell me that when a class D amp failed, they generally took the speakers out with them and that for this reason he didn't use them. Is there any truth to this?

Cheers,
Andrew

 

[theREALdotnet]

I had a bloke at a hifi store tell me that when a class D amp failed, they generally took the speakers out with them and that for this reason he didn't use them. Is there any truth to this?

The class of amplification (A, A/B or D) has nothing to do with it. The quality of engineering of the amp has.

I have rarely heard good engineering advice from retail clerks at HiFi stores.

 

[GXAlan]

It’s the distortion. Audiophiles like it because they believe they can hear “more detail” with that equipment. Of course they do, but it’s information that was never in the recording to start with.

The Sony actually is famed for not having too much detail but still feeling sufficiently detailed.

What I showed in that review was that a null comparison using Deltawave to the full digital source met the threshold of no-audible difference.

I had a bloke at a hifi store tell me that when a class D amp failed, they generally took the speakers out with them and that for this reason he didn't use them. Is there any truth to this?

Class AB designs “typically” have DC speaker protection relays. But there are DC coupled class AB speakers too (like the old PS Audio 200C).

Class D designs do not require a DC relay either.

If an amp without DC protection fails, it can send DC straight to your speaker.

Marantz said they spent extra time validating their PM-10 to ensure that it was safe to go without relays, and after validation opted to go without relays.

So the answer is a bad design can damage your speakers. I am sure there are vintage class D amps that were dangerous.

 

[rwortman]

Not sure the initial proposition is even true. Stereophile routinely gives rave reviews to class D amplifiers. There are 6 of them in the class A and B section of “Recommended Components”. I still consider myself an audiophile even though I didn’t get on board the cables and tweak train. Too big a dose of the “engineering mind”. We do like to think of our equipment as being “special” in ways the non audiophile doesn’t understand. Cheap commodities are just not that attractive. No emotional attachment.

Observation: The ready availability of cheap class D modules and SMPS’ is causing hobbyists that have zero electronics knowledge to build their own amps at home. Usually with good result. Incapable of determining the cause of a bad result. I suspect audio companies will start doing the same thing. Why waste an experienced EE in the amplifier department when all that is required is someone to fit modules in a box and stick switch and logo on the front? I guess most audiophiles don’t want a world where 2 or 3 companies make amp modules and everyone else just packages them. It’s just not very interesting.

Then there is repairability. I can find the fault in a linear power supply in 15 minutes or less. Tracing a signal through a class A or A/B amp is relatively simple. I am batting about .150 at repairing switching power supplies. Usually they stop switching and figuring out why with typical test equipment isn’t easy. I suspect the class D amp modules are the same way. When they blow up, throw them out and get the latest revision.

 

[valerianf]

Well, audiophile belives are not always far from réalité.
I own class D and class AB amps.
As an EE I have designed an industrial audio class D amp.
Here are my thoughts:
Class D is amazing at driving difficults speaker loads.
Class D is amazing at providing a high power with a small footprint and reduced eat.
Class D is amazing to get punchy low frequencies.
But Class D has sometime difficulties high midrange and high frequencies.
But Class D is subject to hiss (in the high frequencies) that is never quantified in the measurements.
Amir may confirm, the beautiful THD numbers measured with the class D amps are measured with a reduced bandwidth in the high frequencies.
It is comparing apples with oranges.
If the required power is not too high I will use class AB for the front and center speakers and class D for all the surround speakers.

 

[Bjorn]

If I am not wrong about dampening factor, Hegels and Rotels go up to insane 1000, so how exactly does that explain that D class is perceived as lean?

Are you trying to tell us that all who find class D sound lean use either Hegel or Rotel amps?
Sometimes it's hard to discuss things online.....

 

[Chrispy]

Ok, I know I shouldn't, but I've been reading feed back on an audiophile site on experiences with various Class D based amplifiers. (Purifi, Ncore, and a couple of others less well known to me)

I expected a bit of bias towards older technologies, but it was close to 100% against class D.

What is it that these people are experiencing? They can't all be wrong can they?

• Is it that they miss the distortion/colour from their class AB amps?
• Has this become normalized/expected?
• Have they been programmed to dislike class D because everyone says it isn't as good, i.e bias?
• Is there actually something else at play here?

Everything I hold as important in audio and electronics in general is about achieving the required performance/specs, 'the truth', or at least as close as we can economically get, am i wrong, because these people would appear to say so.

Didn't bother with the in-between as not necessary to express my opinion, which is basically why would any one trust what passes for an "audiophile's" opinion these days? I love the class D amps I've used for years now.