Purifi Class D

[DuckToller]

5 hours ago, mocenigo said:

are you and Davide willing to engage in a serious discussion or are you content with trolling?

As an Netherland-Bavarian-Italian European guy you're likely to show more humor - even before the first espresso, don't you ?

[Jud]

4 hours ago, mocenigo said:

Actually a square wave is a sum of harmonics.

Ditto for impulses.

 

 

If there are any frequencies that are not an integer multiple of some fundamental, they are inharmonic by definition. It would be rather strange if engineers carefully excluded inharmonics from, for example, the impulses with which they tested.

[audiobomber]

15 hours ago, mocenigo said:

Please, do not embarrass yourself. If you do not understand the mathematics involved there is nothing to be ashamed of, but you are completely wrong. Do not make baseless claims just because to your eyes a musical signal and a sine wave look too different to be correlated.

Do you see me making claims about chemistry or biology? No, because I am not a chemist or a biologist. But I am a mathematician, and can tell you that you are wrong. Sadly, a course in Fourier analysis and signal processing is a bit too complicated to fit in a message on this board.

Typical ASR trashtalk. I suggest you mollify your tone, or you may end up like Mansr, plissken and others who've been sent packing. I used FFT's constantly for four years when I had an ultrasonic detection business. The FFTs that Amir does is on a simple 1kHz sine wave, not a complex musical signal with multitudes of sine waves interacting simultaneously. 

 

John Westlake designed DAC's for Pink Triangle, Cambridge and Audiolab, that sold in the millions. I'll let him make the argument:

the "Power" that sites like ASR are gaining is really concerning and detrimental to the end sound quality IME.

The trouble with the guys on ASR is that they ONLY judge a products performance via "simplistic" technical measurements and IME this does a massive disservice to the general HiFi community - especially those who are scared to listen for themselves...

 

As far as I'm concerned, in the case above, if you want "Best measurements", then buy the cheaper unit and be Happy and "Laugh" at the rest of us  but DON"T dare say the new design sounds worst because in some areas it has poorer measured performance...

You will be surprised how many (it not all) designer I know will privately agree that standard "static" measurements have little refection on sound quality (try as they might to measure and "quantify" sound quality) - but just as in so many walks of life are too afraid to have there voices counted... 

 

https://www.diyaudio.com/forums/digital-line-level/331363-ak4499eq-dac-25.html#post6130649

 

[mocenigo]

14 minutes ago, audiobomber said:

Typical ASR trashtalk. I suggest you mollify your tone, or you may end up like Mansr, plissken and others who've been sent packing.

 

Well, if here one is sent packing for stating the obvious then maybe it is a blessing. I m not a big fan of mob-like threats – "behave ... or else we show you the door", especially when I have been behaving.

 

14 minutes ago, audiobomber said:

I used FFT's constantly for four years when I had an ultrasonic detection business. The FFTs that Amir does is on a simple 1kHz sine wave, not a complex musical signal with multitudes of sine waves interacting simultaneously. 

 

The FFT of a simple 1kHz sine wave is a single value, variable only with intensity, do you know that? Once you have noise and distortion, it is no longer the FFT of a simple 1kHz sine wave.

 

So you were doing FFTs to detect ultrasounds, but you still do not know what those FFTs are.

 

Just as Bruno Putzeys defends his business (I did mention that they are doing marketing in the way they present their work), also John Westlake defends his approach. There is nothing wrong with this, but I also know some designers and they do not agree with what you reported there. Hearsay is not proof, you know.

 

 Roberto

 

14 minutes ago, audiobomber said:

John Westlake designed DAC's for Pink Triangle, Cambridge and Audiolab, that sold in the millions. I'll let him make the argument:

the "Power" that sites like ASR are gaining is really concerning and detrimental to the end sound quality IME.

The trouble with the guys on ASR is that they ONLY judge a products performance via "simplistic" technical measurements and IME this does a massive disservice to the general HiFi community - especially those who are scared to listen for themselves...

 

As far as I'm concerned, in the case above, if you want "Best measurements", then buy the cheaper unit and be Happy and "Laugh" at the rest of us  but DON"T dare say the new design sounds worst because in some areas it has poorer measured performance...

You will be surprised how many (it not all) designer I know will privately agree that standard "static" measurements have little refection on sound quality (try as they might to measure and "quantify" sound quality) - but just as in so many walks of life are too afraid to have there voices counted... 

 

https://www.diyaudio.com/forums/digital-line-level/331363-ak4499eq-dac-25.html#post6130649

 

 

[mocenigo]

33 minutes ago, Jud said:

If there are any frequencies that are not an integer multiple of some fundamental, they are inharmonic by definition. It would be rather strange if engineers carefully excluded inharmonics from, for example, the impulses with which they tested.

 

How do you generate frequencies that are not an integer multiple of some fundamental? Suppose you have a multi-tone IMD test, with frequencies 500*I Hz with I=1,2,3,...,32 – this is not a valid test? But even if you picked 320, 417, 911, and 17100 Hz, they are still multiples of 1 Hz. In fact you need algebraic numbers of the frequencies since with rational numbers you always have a common integral submultiple.  So at which threshold do you stop? 

[mocenigo]

2 hours ago, DuckToller said:

As an Netherland-Bavarian-Italian European guy you're likely to show more humor - even before the first espresso, don't you ?

 

Well, you know, I am tired of the old wrong argument "these sines have nothing to do with music". There are reasons for criticising the completeness of Amir's tests, and many good ones. I can list measurements that should be there (and are not), and have mentioned some, but the non-equivalence above is a fallacy. I expect criticism to be constructive, not just dismissal without a justification.

[audiobomber]

33 minutes ago, mocenigo said:

The FFT of a simple 1kHz sine wave is a single value, variable only with intensity, do you know that? Once you have noise and distortion, it is no longer the FFT of a simple 1kHz sine wave.

Semantics. The FFT is generated by a simple 1kHz sine wave, due to the way the device handles or mishandles it. But a simple sine wave or two is not an analog of music, which contains multitudes of overlapping and interacting sine waves. I tried a Topping DAC based on ASR measurements. It sucked. 

 

I'm done with this, it's a waste of time.

[DuckToller]

12 minutes ago, mocenigo said:

 

Well, you know, I am tired of the old wrong argument "these sines have nothing to do with music". There are reasons for criticising the completeness of Amir's tests, and many good ones. I can list measurements that should be there (and are not), and have mentioned some, but the non-equivalence above is a fallacy. I expect criticism to be constructive, not just dismissal without a justification.

@mocenigo
My friend, I referred specifically to Jud's comment about the audio engineers, that was the one you quoted.

With everything else  from your arguments I am mostly d'accord, but I suspect that some sensitive ears aren't happy with your tiredness influencing your tonality. Especially when opinions and facts are clashing, the complexity of foreign languages and different cultural backgrounds (by origin or profession) show more importance than we would usually wish for. And feeling provoked in their comfort zone.

Even most members here are career audiophiles (means they are not just starting their hobby), not all of them can deal well with the sometimes inherent acidity of objective facts. Acidity in tems of telling them that they are plain wrong because these facts are different to their experience. And then are some that can't stop putting opinion and anecdotal experience into generalisations against objective scenarios and fight the facts.

Personally, I think it is a severe put off when people starting threatening you (Yes I think the reference of MansR was exactly that!), because you serve well facts which doesn't fit their personal views, and they start fighting you about your tonality.

I personally enjoy your posts most of the times, and would love to read a kind of workshop on signal processing from you in the Blog section.

[barrows]

13 minutes ago, audiobomber said:

Semantics. The FFT is generated by a simple 1kHz sine wave, due to the way the device handles or mishandles it. But a simple sine wave or two is not an analog of music, which contains multitudes of overlapping and interacting sine waves. I tried a Topping DAC based on measurements. It sucked. 

 

I'm done with this, it's a waste of time.

On the Topping, I had the same experience.  I got, I think it was the D-90, with the new AKM chip (at the time) because it was an affordable way to hear what the AKM chip could do with high rate DSD input.  The DAC was just OK.  It was quiet and detailed, but certainly nothing special.  I tend to straddle the line between the importance of measurements and listening personally.  I do believe everything can be measured, for sure, after all, we can "look" at things in even in the quantum realm!  But the standard set of measurements, as shown say at ASR are clearly inadequate to describe all aspects of the performance of audio components.

Bruno Putzeys simulates, builds a proto, measures, listens, and then repeats the process until the the measurements and the listening experience equal the performance which was predicted in the maths and sims.  This seems a reasonable approach to me.  If he finds a "problem" when listening, he goes back and tries to find a measurement which indicates that problem, and then goes about solving it.  So, he does respect the listening as a tool in the development process-but as an engineer, he wants to confirm the listening experience with objective measurements so that he actually knows when the problems are solved, objectively.  

I agree that Amir is a bit short sighted in his approach to evaluating things.  He seems a bit like a child with a new toy (his AP); it is a bit like the old saying: when you have a hammer, everything looks like a nail!  When people kneel at the alter of ASR, and blindly accept the notion that a few simple measurements actually define the performance of an audio component, it is a problem for the advancement of audio as a whole.  I have a suggestion for those who think these few measurements are all which matter.  Have a listen to a Mola Mola Tambaqui DAC, vs the perfectly measuring Topping DAC of your choice, on a really good, full range, high end system set up in a good room (not headphones).  The difference will not be subtle!  This test is all one needs to do to understand that a simple set of measurements is inadequate to describe the full range of audio component performance. 

[audiobomber]

7 minutes ago, DuckToller said:

Personally, I think it is a severe put off when people starting threatening you (Yes I think the reference of MansR was exactly that!), because you serve well facts which doesn't fit their personal views, and they start fighting you about your tonality.

It was not a threat, it was a warning. I don't have the power to ban, but the moderator does, and has several times, for exactly the same arrogant and dismissive tone that our friend here favors. I don't like being called ignorant or stupid, which is the subtext in the last couple of posts @mocenigo sent my way. 

[DuckToller]

2 minutes ago, audiobomber said:

It was not a threat, it was a warning. I don't have the power to ban, but the moderator does, and has several times, for exactly the same arrogant and dismissive tone that our friend here favors. I don't like being called ignorant or stupid, which is the subtext in the last couple of posts @mocenigo sent my way. 

.. touché ...

[davide256]

6 hours ago, mocenigo said:

My friend, the fact that the human brain is slow does not mean that sufficient information to describe that “impression”

may not be in a short sound sample.

Your argument is a non sequitur.

Thats called evading the question. A no points answer on any exam

[Jud]

1 hour ago, mocenigo said:

 

How do you generate frequencies that are not an integer multiple of some fundamental? Suppose you have a multi-tone IMD test, with frequencies 500*I Hz with I=1,2,3,...,32 – this is not a valid test? But even if you picked 320, 417, 911, and 17100 Hz, they are still multiples of 1 Hz. In fact you need algebraic numbers of the frequencies since with rational numbers you always have a common integral submultiple.  So at which threshold do you stop? 

 

As we used to say in law, this argument "proves too much." The inharmonics of percussion instruments and the inharmonic attacks of nearly every musical source including the human voice contain frequencies that are each multiples of 1Hz, but are not integer multiples of *each other*.

[Jud]

38 minutes ago, barrows said:

On the Topping, I had the same experience.  I got, I think it was the D-90, with the new AKM chip (at the time) because it was an affordable way to hear what the AKM chip could do with high rate DSD input.  The DAC was just OK.  It was quiet and detailed, but certainly nothing special.  I tend to straddle the line between the importance of measurements and listening personally.  I do believe everything can be measured, for sure, after all, we can "look" at things in even in the quantum realm!  But the standard set of measurements, as shown say at ASR are clearly inadequate to describe all aspects of the performance of audio components.

Bruno Putzeys simulates, builds a proto, measures, listens, and then repeats the process until the the measurements and the listening experience equal the performance which was predicted in the maths and sims.  This seems a reasonable approach to me.  If he finds a "problem" when listening, he goes back and tries to find a measurement which indicates that problem, and then goes about solving it.  So, he does respect the listening as a tool in the development process-but as an engineer, he wants to confirm the listening experience with objective measurements so that he actually knows when the problems are solved, objectively.  

I agree that Amir is a bit short sighted in his approach to evaluating things.  He seems a bit like a child with a new toy (his AP); it is a bit like the old saying: when you have a hammer, everything looks like a nail!  When people kneel at the alter of ASR, and blindly accept the notion that a few simple measurements actually define the performance of an audio component, it is a problem for the advancement of audio as a whole.  I have a suggestion for those who think these few measurements are all which matter.  Have a listen to a Mola Mola Tambaqui DAC, vs the perfectly measuring Topping DAC of your choice, on a really good, full range, high end system set up in a good room (not headphones).  The difference will not be subtle!  This test is all one needs to do to understand that a simple set of measurements is inadequate to describe the full range of audio component performance. 

 

Blind test challenge or objection coming in 3...2...1....

 

😉

[davide256]

11 minutes ago, Jud said:

 

As we used to say in law, this argument "proves too much." The inharmonics of percussion instruments and the inharmonic attacks of nearly every musical source including the human voice contain frequencies that are each multiples of 1Hz, but are not integer multiples of *each other*.

I believe that what determines the character/type of instrument is the mixture, relative loudness levels of the different harmonics. Instability  in maintaining the proper relationship is what I think makes something "sound like" vs "sounds as".  Trying to extract the best sound possible

took hours of daily practice cementing "muscle memory" and diaphragm  support to get the richest sound out of a brass instrument.

 

[Matias]

3 hours ago, audiobomber said:

The FFTs that Amir does is on a simple 1kHz sine wave, not a complex musical signal with multitudes of sine waves interacting simultaneously. 

 

John Westlake designed DAC's for Pink Triangle, Cambridge and Audiolab, that sold in the millions. I'll let him make the argument:

the "Power" that sites like ASR are gaining is really concerning and detrimental to the end sound quality IME.

The trouble with the guys on ASR is that they ONLY judge a products performance via "simplistic" technical measurements and IME this does a massive disservice to the general HiFi community - especially those who are scared to listen for themselves...

 

As far as I'm concerned, in the case above, if you want "Best measurements", then buy the cheaper unit and be Happy and "Laugh" at the rest of us  but DON"T dare say the new design sounds worst because in some areas it has poorer measured performance...

You will be surprised how many (it not all) designer I know will privately agree that standard "static" measurements have little refection on sound quality (try as they might to measure and "quantify" sound quality) - but just as in so many walks of life are too afraid to have there voices counted... 

 

https://www.diyaudio.com/forums/digital-line-level/331363-ak4499eq-dac-25.html#post6130649

 

 

Sorry to say but you and John are the ones oversimplifying. ASR does measure multitone as well since the beginning. For more than a year there have been multiple frequencies measured in power x THD+N, and more recently power x IMD.

 

What he does is ranking them by 1kHz 5W into 4 ohms SINAD, which we all agree that is not everything. But it has been discussed a thousand times that it serves as a proxy/predictor of an overall good measuring amplifier. Which is true: a top measuring 1kHz SINAD Purifi also is a top measuring in IMD. See here from SoundStage measurements (edit: AS automatically removes links to ASR, how low...)

 

2 hours ago, barrows said:

Have a listen to a Mola Mola Tambaqui DAC, vs the perfectly measuring Topping DAC of your choice, on a really good, full range, high end system set up in a good room (not headphones).  The difference will not be subtle!  This test is all one needs to do to understand that a simple set of measurements is inadequate to describe the full range of audio component performance. 

 

Funny you mention that, as some months ago I brought my RME ADI-2 DAC (with iFi iPowerX PS, AKM 4493 version) to play in my main system (based on Thiel CS3.7, NC500 back then, treated room, FIR room EQ) in place of my Makua preamp+DAC. Non blind, non level matched, just subjective. There were differences, but I would say they were tiny overall. I own both devices, so no bias to favor one or the other. If anything made me impressed by the RME, and questioning the value of the Makua. Still I will not sell it, it is already paid for, I love it as well. :)

[Jud]

1 hour ago, davide256 said:

Trying to extract the best sound possible

took hours of daily practice cementing "muscle memory" and diaphragm  support to get the richest sound out of a brass instrument.

 

When I was very young I played French horn absolutely dreadfully for a few years. Does that count? 😉

[Allan F]

17 minutes ago, Jud said:

When I was very young I played French horn absolutely dreadfully for a few years. Does that count? 😉

 

Only if you quit to spare those who had to listen to your playing. 🙂

[mocenigo]

3 hours ago, audiobomber said:

I tried a Topping DAC based on ASR measurements. It sucked. 

They differ mostly in the output stages and impedance compatibility should ALWAYS be considered, whether you are connecting a 100€ DAC or a 100.000€ one.
 

Anyway, the owners of Purifi disagree with you since they lug around a Topping (and one of them asked me whether it was plausible that he could not hear a difference between the Tambaqui and the D90 non-MQA first series - I omit the name or Bruno will punch him :-)

 

Also: read the TAS review of the D90SE. In this case I am going to say you made a sighted and totally biased comparison.

 

3 hours ago, audiobomber said:

'm done with this, it's a waste of time.

On this we agree 100%.

[PYP]

23 minutes ago, mocenigo said:

Anyway, the owners of Purifi disagree with you since they lug around a Topping (and one of them asked me whether it was plausible that he could not hear a difference between the Tambaqui and the D90 non-MQA first series - I omit the name or Bruno will punch him :-)

 

I've never heard two DACs sound identical.  Or two pieces of any kind of gear.  

[barrows]

13 minutes ago, mocenigo said:

Anyway, the owners of Purifi disagree with you since they lug around a Topping (and one of them asked me whether it was plausible that he could not hear a difference between the Tambaqui and the D90 non-MQA first series - I omit the name or Bruno will punch him :-)

I easily heard what I would consider vast differences between my Bricasti M3 and the D90 (first version), and my DIY DSC-2 DAC, given DSD 256 feed from HQPlayer and direct conversion of the DSD stream in the D-90.  This was here in my room under direct comparison.  My experience of the Tambaqui has been in different system contexts by memory only, but from those memories it outperformed any other DAC of my experience.  Main differences were in the ability to present a naturalness of tone and dynamic expression, while remaining extremely detailed.  The D-90, while almost as detailed, missed out on sounding natural, or dynamic, for that matter.  The differences in implementation in these DACs is quite large-as one who has built a lot of DACs, the tiny, and unsophisticated power supply section of the D-90 is suspect as a possible cause.

For what it was, the D-90 was quite a good value, and I really wanted to like it, but it did not stand up to other more sophisticated designs here, so it was sold after about 6 weeks of comparisons.

I have been in the audio world for a long time, so. Please do not attempt to suggest I am blind, or blinded.  Professionally I have been trusted to evaluate various component, and component parts, for sound quality, and I have been trained to be able to distinguish biases, and guard against them.  Many times I have been surprised in evaluations when the result of actual listening tests was much different than my expectations. 

[audiobomber]

33 minutes ago, mocenigo said:

this case I am going to say you made a sighted and totally biased comparison

To be clear, it was a D50S I bought. I compared it with a cheaper Modi 3. 

 

TAS and Stereophile are just another opinion, nowhere near as reliable as extended listening in my own system.

[PYP]

1 hour ago, Matias said:

What he does is ranking them by 1kHz 5W into 4 ohms SINAD, which we all agree that is not everything. 

 

 

Funny you mention that, as some months ago I brought my RME ADI-2 DAC (with iFi iPowerX PS, AKM 4493 version) to play in my main system (based on Thiel CS3.7, NC500 back then, treated room, FIR room EQ) in place of my Makua preamp+DAC. Non blind, non level matched, just subjective. There were differences, but I would say they were tiny overall. I own both devices, so no bias to favor one or the other. If anything made me impressed by the RME, and questioning the value of the Makua. Still I will not sell it, it is already paid for, I love it as well. :)

I've only read ASR briefly because many participants seem to have severe IBS.  Life is too short.  But if the comparison graph, which may be the only thing that non-technical novices look at, is not really relevant, what is the true utility?  

 

I think your comparison of DACs in one's own system and with your own ears is the only relevant one.  I have tried a Schiit Audio Modius DAC ($229) fed by the Grimm Audio MU1.  The MU1 is a DDC that does some of the complicated math (giving @mocenigo a few moments of rest) before handing off to the DAC.  The MU1 handled the volume control as well.  Result?  Sounded very nice, and if "pleasant and enjoyable" was one's goal, you could stop right there. 

 

After a week, the Tambaqui took its place.  If "much like the live event" is one's goal, this DAC is preferred.  Of course, the context is very favorable to the Tambaqui (I'm assuming Bruno used the Kaluga amps when he designed his DAC, which are the amps I use).  The Tambaqui replaced a PS Audio Directstream.  Once the Tambaqui was warmed up, the in-home demo took about 5 minutes before a decision was made to purchase the Tambaqui.  

[PYP]

25 minutes ago, barrows said:

I easily heard what I would consider vast differences between my Bricasti M3 and the D90 (first version), and my DIY DSC-2 DAC, given DSD 256 feed from HQPlayer and direct conversion of the DSD stream in the D-90.  This was here in my room under direct comparison.  My experience of the Tambaqui has been in different system contexts by memory only, but from those memories it outperformed any other DAC of my experience.  Main differences were in the ability to present a naturalness of tone and dynamic expression, while remaining extremely detailed.  The D-90, while almost as detailed, missed out on sounding natural, or dynamic, for that matter.  

While I don't believe YouTube is a good medium for comparing gear, I did watch a comparison of the Tambaqui and a similarly priced dCS.  What was very apparent from the video was the difference in portrayal of rhythm.  The difference was large and, for my tastes, favored the Tambaqui.  

 

Of course, I couldn't hear the differences in tone and timbre, which in my setup is a particular strength of the Tambaqui and a quality that enables me to hear what the musicians are expressing.    

[PYP]

22 hours ago, mocenigo said:

 

There are two ways a system can be "revealing".

 

For the audiophilics (sic!) it means that the electronics are badly designed enough that, for instance, the additional electrical characteristics of intentionally bad cables (the expensive ones) modify frequency response and phase. This is what leads to a waster of money in exotic power cords, interconnects, speaker cables, accessories, etc.

 

 

 Roberto

 

From Mola Mola website's description of the Kaluga amps:  2 pairs of Furutech binding posts. Biwired directly to the amplifier PCB using Kubala-Sosna cable.