Review and Measurements of PS Audio PerfectWave DirectStream DAC

[Guermantes]

This is a reasonable engineering goal but not a satisfying definition/goal in the real world. Eventually what matters is how a piece of equipment sounds to somebody, not how it is measured. And just because something is easily measured does not mean it is the right measure. If something is measured beyond human capabilities ti hear then that should not be part of the ranking in some composite number.

I'm afraid that I simply don't agree with you. It is perfectly valid to evaluate how a piece of equipment measures since this indicates how it statisfies real world engineering goals (to borrow your terminology). How is the psychological aspect of how it sounds to any individual -- an aspect that will probably vary greatly depending on mood, physiology, environment, what sort of day they are having -- supposed to be anymore "real world" than what measurements show? If anything, the measurements allow us to rule out bias and listening idiosyncracies. Our ears are not the great arbiters of audio truth you seem to imply, unless it's a phenomenological truth you are searching for.

The bridge analogy is off the mark. Noise and distortion can be audible artefacts, so SINAD ranking seems perfectly reasonable even when it drops below apparently audible levels. In my work I constantly battle digging intelligible speech out of the noise floors of recordings systems -- what I would give for a SNR of 120 dB!!

The whole history of sound recording technology has been a battle to reduce noise and distortion, and the standard measurements in devices such as the AP analyser reflect this. If these are not the right measurements, then you should probably take that up with the AES, et.al.

 

[GTsmokeya84]

So I have read this whole thread in my free time so yes it took this long to post a reply. I for one appreciate all this site has done and contributed to this industry/hobby. This measurement is disappointing to say the least. If I were PS Audio I would be embarrassed and maybe avoid adding to the discussion and just go the the drawing board and try again.

I feel the few comments I have read from the PS Audio forum are more disappointing than results.

Their amps interest me a great deal and have put serious thought into dropping some coin on one one or two. This review and their response has given me serious pause. Maybe their amps measure well IDK but I will wait and continue to watch this great site for more knowledge and frankly go as far as putting my money where my mouth is and become a Patreon donor today.

Thank you again to all the great contributions and hard work @amirm put in this site!

 

[pkane]

@amirmMany of you would have guessed that PerfectWave DirectStream DAC would not do well on the bench.

This reads like; because this is marketed as High End / Audiophile we already know that it is going to perform badly

Or maybe it reads like: because there is a headless panther in the photo, many would have guessed that this DAC would not do well on the bench.

 

[mkawa]

So I have read this whole thread in my free time so yes it took this long to post a reply. I for one appreciate all this site has done and contributed to this industry/hobby. This measurement is disappointing to say the least. If I were PS Audio I would be embarrassed and maybe avoid adding to the discussion and just go the the drawing board and try again.

I feel the few comments I have read from the PS Audio forum are more disappointing than results.

Their amps interest me a great deal and have put serious thought into dropping some coin on one one or two. This review and their response has given me serious pause. Maybe their amps measure well IDK but I will wait and continue to watch this great site for more knowledge and frankly go as far as putting my money where my mouth is and become a Patreon donor today.

Thank you again to all the great contributions and hard work @amirm put in this site!

before you consider forking over a double digit percentage of a new car worth of cash to them, consider this:

THEY ARE TRYING TO SELL AN UNMANAGED, TINY ETHERNET SWITCH TO PEOPLE FOR THOUSANDS OF DOLLARS BY CLAIMING THAT IT POSITIVELY AFFECTS SOUND QUALITY IN A STREAMING DEVICE

 

[GrimSurfer]

I think that people here secretly want each product to redefine the SOTA. Why? Because, as audio aficionados, we'd like to believe that there will be something even better on the shelf next time we go shopping.

Realistically, however, many here cannot ignore our rational inner voices that tell us that some companies succeed while a great many fail.

If you want to define anticipation, tune-in the days leading up to the release of a Benchmark test. It's not that any of us hold a bias towards all things made in Rochester. It's that they have released products that have performed at or near the SOTA so many times that we're genuinely interested to see if the streak continues.

Conversely, a company producing gear that regularly falls short piques our interest. We'd secretly like to see real improvement but an extrapolated trend line prepares us for failure. It does not lead us there. That is entirely a matter of how the gear performs under lab conditions.

 

[GTsmokeya84]

before you consider forking over a double digit percentage of a new car worth of cash to them, consider this:

THEY ARE TRYING TO SELL AN UNMANAGED, TINY ETHERNET SWITCH TO PEOPLE FOR THOUSANDS OF DOLLARS BY CLAIMING THAT IT POSITIVELY AFFECTS SOUND QUALITY IN A STREAMING DEVICE

Very true and considering my degree and background was in IT and networking that is kind of hilarious. I got out of that industry over 15 years ago but still pretty funny.

 

[Primare Knob]

Or maybe it reads like: because there is a headless panther in the photo, many would have guessed that this DAC would not do well on the bench.

That is kind of a dead give away. Makes sense now.

 

[AndrovichIV]

That worries me.
I have come here because I wanted another tool in search of best value/performance gear.
Me personally doesn't know half what is written here. But I used his measurements to know how good a product is. Just like magazines use words to describe how good a product is.
But now I read on this other site that maybe the measurements are not done in the right way. This leads to a situation where I don't know what to believe anymore. Because I don't know all these technical stuff.
So it would be great if Amir would address these points.
Now it seems like there can be more different measurements taken and that the analyzer was not calibrated right. And we are again back at the start. Because then we have to choose whose measurements we believe. This is frustrating for someone with little knowledge.

For the sake of argument assume that there's an error in the measurements. For instance, the measured performance is 15% than in reality. Since the methodology is the same across DAC's, A will be better than B, even in the presence of such an error in measurement.

Results would not be informative if they were completely random. However, it's very unlikely that they are random as they often approximate official specs and specs posted in other sites.

So, a probabilistic statement that you can make is that with a fair degree of confidence ASR measures are informative, and in this particular case the DAC underperforms alternatives.

 

[tobes]

The result here doesn't surprise me.
I previously owned a PS Audio DSjr (lower cost Directstream dac with a conventional output stage - no transformers) - frankly I found the Topping D50 to sound subjectively cleaner and more detailed.
The DSjr was the second high end dac I purchased - prior to that I had the Schiit Yggdrasil (A1 version). Yeah, I know - this was before the Stereophile review and long before ASR was around. I tried to get comfortable with the Yggdrasil sound over about 6 months, but eventually had to admit to myself that my older Grace Design dac imposed less of a 'fingerprint' on the music.

 

[amirm]

@amirm

I am not sure how to read this:
Conclusions
Many of you would have guessed that PerfectWave DirectStream DAC would not do well on the bench.

This reads like; because this is marketed as High End / Audiophile we already know that it is going to perform badly

Not at all. I say that because it is yet another re-invention of the DAC. With some rare exceptions, these boutique DACs always underperform special-built silicon DACs.

 

[GrimSurfer]

The result here doesn't surprise me.
I previously owned a PS Audio DSjr (lower cost Directstream dac with a conventional output stage - no transformers) - frankly I found the Topping D50 to sound subjectively cleaner and more detailed.
The DSjr was the second high end dac I purchased - prior to that I had the Schiit Yggdrasil (A1 version). Yeah, I know - this was before the Stereophile review and long before ASR was around. I tried to get comfortable with the Yggdrasil sound over about 6 months, but eventually had to admit to myself that my older Grace Design dac imposed less of a 'fingerprint' on the music.

I think it takes a fair amount of courage to admit that to yourself and move on. Steadfastly sticking to something that doesn't perform achieves nothing more than conditioning ears to poor sound, which has a really bad effect over time.

Well done, Sir!

 

[JJB70]

This is a reasonable engineering goal but not a satisfying definition/goal in the real world. Eventually what matters is how a piece of equipment sounds to somebody, not how it is measured. And just because something is easily measured does not mean it is the right measure. If something is measured beyond human capabilities ti hear then that should not be part of the ranking in some composite number.

Take an analogy. Say there is a site that tested the traffic resonance of all bridges in a country and ranked them. One might say that a bridge that minimized the resonances (from traffic alone, don’t want to complicate with resistance to winds, earthquakes, etc) was a better engineered design. That is fine. You may have measurements that detect the tiniest of resonances that cannot even be felt. You can even proclaim that it is the right criterion.

But, if you cannot establish any correlation with that measurement with safety of that bridge (except at the extremes), then one cannot make any claims about the quality of the bridge from a safety perspective.

Right now, these equipment rankings with SINAD and a thumbs up and thumbs down create incorrect inferences as it relates to audibility of equipment, none of which have perfect transparency. It also creates openings for companies like PS Audio or NAD to dismiss measurements and/or obfuscate the issue.

For example, the limitations of this methodology to be understood correctly is precisely at the bottom of questions like the below that was asked in another thread.



This sort of a thing needs to be avoided on its own with better explanation and understanding of what the reviews mean.

I would argue that the design goal of audio equipment should be not to have a sound as such but to faithfully extract, amplify and play source material accurately. Any sonic signature should form part of the source material. If people like coloured sound then use EQ or DSP, one of the great mysteries of audio is why so many audiophiles have a pathological aversion to tone controls and DSP then buy deliberately coloured equipment. Why not buy accurate equipment and then colour it however you like with EQ and DSP. If it was a cheap and cheerful product sold honestly it would be different (for example the Polaris headphone amp reviewed elsewhere on this website is very open about reproducing a valve sound rather than measuring well and is modestly priced) but this thing is a $6000 DAC sold as hifi.

The bridge analogy is interesting. In a mechanical structure there will be thousands of calculations forming part of the design and an awful lot of measurements but it is not about creating perfection, it is about meeting a specification and building something which is fit for purpose. The problem for audio companies in the high end is that if you consider the specification as being to deliver audibly transparent performance, which does not need SOTA measured performance, then this has been commoditised up to the speakers and can be found for low cost. That doesn't make expensive audio irrelevant as things like industrial design, build quality, through life support, durability, functionality, measured performance and just plain wow factor still matter to many buyers. However a lot of high end equipment equipment is not particularly well made or blessed with good industrial design and if it is not about the SQ and it does not tick the boxes on build and design and measures badly then it is hard to see why some gear should exist.

 

[VintageFlanker]

I would argue that the design goal of audio equipment should be not to have a sound as such but to faithfully extract, amplify and play source material accurately.

Well, that is exactly what "High Fidelity" is supposed to mean. Looks like a ton of people forgot about it...

With some rare exceptions, these boutique DACs always underperform special-built silicon DACs.

Am I wrong, or Chord Electronics is the only exception known on ASR?

 

[audimus]

It is perfectly valid to evaluate how a piece of equipment measures since this indicates how it statisfies real world engineering goals (to borrow your terminology).

I have no problem with these measurements being used as engineering goals, real or virtual for yourself. Consumers in the real world don’t have engineering goals (except for a niche tech-nerds). They have audibility and price goals and perhaps reliability goals related to engineering. If you don’t agree with this premise, then there is no debate since we have very different perspective of what the real world is. We will agree to disagree.

If a 100db SINAD device costs $1500 and a 90db SINAD device costs $500 and the features are identical and aesthetically acceptable, should one buy the more expensive one? This is where the engineering goal criterion breaks down.

Nobody except perhaps the tech-nerds here will argue for the more expensive unit because it satisfies the engineering goals better. Good for them.

But how do you answer the question from a user I posted earlier. Try answering that seriously and see what makes sense. No hemming and hawing. May be you can and may be you cannot but hey I like the better numbers because 24-bits, jargon, jargon, dynamic range, jargon, jargon, controlled tests, no difference, jargon, jargon, etc.

It is fine if a bunch of similar minded people made the engineering goal their criterion and created an echo chamber for themselves here but that is not a solution to anybody outside. The conflict happens when these reviews don’t stay within the choir here but pretend to have real world, consumer implications outside it and solicit comments from outside or pretend to have implications on the industry that caters to the outside.

That is where the problem is. Instead of looking for ways to solve the problem by identifying the limitations here and its applications in the real world of people, I see people repeating the same talking points like the Bogleheads use the “active management bad, indexing good” mantra over and over again. That is a cult.

It has nothing to do with psychology of hearing at the base level to hide under that nebulous term.

Almost every consumer outside this echo chamber will want to know things like -

Does the higher SINAD position in the ranking table mean that the sound will be better than the one below it and so should I buy the one higher up at a higher price? Should I not buy this unit at the lower end of the scale because I am going to be unhappy with that sound? If two units have the same SINAD ranking, are they going to sound the same? I liked the sound of my old amp from brand X but I need a replacement. What can I buy that will sound similar?

If those are banal questions or questions that are based on subjective preferences and something that we should not bother with, then let us sit in this artificial world for ourselves with a groupthink that we have the best goal. Or we could, in the tradition of science, try to study what bridges the gap between the measurements and those needs.

I would say the engineering approach at the moment utterly fails to answer any of the above in any satisfactory way. And that is what I meant by solving real world goals.

But if it is fine to have an echo chamber here in that elusive goal of perfection where the chase is more important than the result, fine by me.

 

[audimus]

I would argue that the design goal of audio equipment should be not to have a sound as such but to faithfully extract, amplify and play source material accurately. Any sonic signature should form part of the source material. If people like coloured sound then use EQ or DSP, one of the great mysteries of audio is why so many audiophiles have a pathological aversion to tone controls and DSP then buy deliberately coloured equipment. Why not buy accurate equipment and then colour it however you like with EQ and DSP. If it was a cheap and cheerful product sold honestly it would be different (for example the Polaris headphone amp reviewed elsewhere on this website is very open about reproducing a valve sound rather than measuring well and is modestly priced) but this thing is a $6000 DAC sold as hifi.

The bridge analogy is interesting. In a mechanical structure there will be thousands of calculations forming part of the design and an awful lot of measurements but it is not about creating perfection, it is about meeting a specification and building something which is fit for purpose. The problem for audio companies in the high end is that if you consider the specification as being to deliver audibly transparent performance, which does not need SOTA measured performance, then this has been commoditised up to the speakers and can be found for low cost. That doesn't make expensive audio irrelevant as things like industrial design, build quality, through life support, durability, functionality, measured performance and just plain wow factor still matter to many buyers. However a lot of high end equipment equipment is not particularly well made or blessed with good industrial design and if it is not about the SQ and it does not tick the boxes on build and design and measures badly then it is hard to see why some gear should exist.

The bridge analogy was to drive the point home that one can set up an arbitrary goal of perfection and even believe that is the right goal that all bridge builders should aim for and pretend that everything else especially if it is difficult to measure is unimportant or subjective. They will be totally irrelevant to the real world. It is easy to see that in the bridge category when like us one is outside it but from the inside it is as hard as for that hypothetical bridge objectivists to see the limitations of their own goal living in that echo chamber.

 

[beefkabob]

This thread updates so often, the longer I read it, the farther I am from the newest post.

As has been said 1000 times before, if the equipment is transparent, you can always add EQ, tone control, and software adjustments to introduce whatever distortion you'd like. Certainly in the pro audio world, there are more than a handful of plugins to get various desired effects for every individual instrument. Of course we're not listening to instruments, we're listening to recordings, so whatever distortions you introduce will be a bit scattershot in their application.

As for audible transparency, that's been discussed 1000 times before, too. Amir has even discussed differing opinions on what is and isn't audible, based in research, of course. Somewhere in those top two tiers of DACs, you're just not going to hear a difference anymore. Possibly below that level, depending on your hearing, training, amp, and speakers or headphones.

 

[LTig]

[..]If a 100db SINAD device costs $1500 and a 90db SINAD device costs $500 and the features are identical and aesthetically acceptable, should one buy the more expensive one? This is where the engineering goal criterion breaks down.

Nobody except perhaps the tech-nerds here will argue for the more expensive unit because it satisfies the engineering goals better. Good for them.

A unit with a SINAD of 120 dB or more is transparent under all circumstances because it is impossible for humans to hear noise or distortion stemming from this unit. So from a perfectional viewpoint you cannot make a mistake if you decide to buy such a unit.

Regarding your examples the decision should be taken according to environment and usage because both units are not transparent under all circumstances. I'd say that under normal home listening conditions (speakers with 90 dB efficiency or less, no more than 100W power per speaker available) both units should satisfy the listener equally well. If you listen very loud and have the proper play back chain or very efficient speakers then the unit with 90 dB SINAD may not be suited to the task.

For professional use in recording studios I would buy neither of them. Here a unit with SINAD of 120 dB or more should be used, otherwise noise and distortion may end up in the final product for the user.

But how do you answer the question from a user I posted earlier. Try answering that seriously and see what makes sense. No hemming and hawing. May be you can and may be you cannot but hey I like the better numbers because 24-bits, jargon, jargon, dynamic range, jargon, jargon, controlled tests, no difference, jargon, jargon, etc.

Buying a unit based on a single number is plain stupid. You have to read the review.

[..]Almost every consumer outside this echo chamber will want to know things like -

Does the higher SINAD position in the ranking table mean that the sound will be better than the one below it and so should I buy the one higher up at a higher price? Should I not buy this unit at the lower end of the scale because I am going to be unhappy with that sound? If two units have the same SINAD ranking, are they going to sound the same? I liked the sound of my old amp from brand X but I need a replacement. What can I buy that will sound similar?

If reading the review does not help people can still ask - and they do, when look into the forums at ASR.

[..]I would say the engineering approach at the moment utterly fails to answer any of the above in any satisfactory way. And that is what I meant by solving real world goals.

If unsure a user can always buy a unit with the best SINAD value and be sure that it will not disappoint him (maybe except AVRs ). This is a very nice feeling and solves a real world problem.

 

[FooYatChong]

If a 100db SINAD device costs $1500 and a 90db SINAD device costs $500 and the features are identical and aesthetically acceptable, should one buy the more expensive one? This is where the engineering goal criterion breaks down.

Think it's the other way around. With the information on ASR you know what you're paying for. Only play cd's? A $100 DAC may be all you need. Care about features and design, spend some more.

In contrast to the 'real world', where the 12k DAC will always be way better than the 8k DAC and you're left with the question 'How much does it take to lift that veil?'. Will 3k do? While being at risk endingup with a 75db SINAD device wondering why you can't hear a difference between mp3 and high res audio.

 

[Thomas savage]

From a post on PS Audio Forum:

View attachment 34332

Members here know that I have praised products from iFi and Schiit when they perform well.

Schiit Modi 3 review: https://www.audiosciencereview.com/...w-and-measurements-of-schiit-modi-3-dac.4742/



Ifi iDSD Black Edition: https://www.audiosciencereview.com/...dsd-black-label-dacs-and-headphone-amps.3717/



As to UpTone, their product had a clear design flaw which I discovered. They [Alex Crespi, business partner to Swensen and alias Superdad] fought and fought, only to agree at the end that the measurements were correct and isolated power supply was not isolating as my tests showed: https://www.audiosciencereview.com/...regen-review-and-measurements.1829/post-46792


Leading to redesign:


So yes, Swenson designed products that create problems because he didn't know how to test them. At best they do nothing good. At worse, they mess up the performance of the system. This is the power of objective measurements. They reveal the truth in audio. Audiophile listening doesn't.

This is probably both the best post on ASR and the most satisfying and revealing.

God knows they gave you a kicking but you showed all your best qualities and were vindicated. It was hard at the time but it's was the best thing to happen for us.

 

[Krunok]

This is probably both the best post on ASR and the most satisfying and revealing.

God knows they gave you a kicking but you showed all your best qualities and were vindicated. It was hard at the time but it's was the best thing to happen for us.

Why do you guys even bother with what some "scumbag" (by his own admission) is saying?