Review and Measurements of PS Audio PerfectWave DirectStream DAC

[amirm]

Thank you for your reviews Amir I had been thinking about PS audio gear and researching it for long time. I think Paul is a nice guy and I don't necessarily agree with everything he says but he can be insightful from time to time. With that said I don't trust companies that don't post the graphs just spouting off a bunch of numbers with no visual representation isn't enough for me to spend my hard earned money on a product. I guess I will hold on to my Benchmark DAC HGC 2 a little longer...

My pleasure. My impression of Paul is the same. He obviously has good historic and actual knowledge of audio. So many times what he describes are fine and correct. You just have to know the boundary of what is real science and what then becomes speculative stuff he talks about.

On numbers, they leave out useful stuff but then include misleading ones like this part of the spec:

146 dB just means it is using 24 bit precision internally. Nothing to write home about since we deal with 24-bit audio. If it used much higher resolution, then we could talk.

To with, here is the internal resolution of my APx555 analyzer on display, analyzing the j-test jitter signal in digital domain (as above):

Notice how it is able to show signal components down to -180 dB!

Of course what matters is the analog resolution of the DAC as that is what we listen to, not internal digital sample presentation as they report above. Clear attempt to show misleading numbers to impress.

 

[imagidominc]

I'm not feeling a lot of warmth in this discussion. Better add some more distortion.

BZZZZZZZZZ.

 

[RayDunzl]

Re: Paul Miller

Traditionally he has built his own instrumentation -- hardware and software.

I don't know him, but remember seeing his name in the old stack of Stereophiles...


A J.A. measurement excerpt from 2007:

https://www.stereophile.com/content/nagra-cdp-cd-player-measurements

 

[Soniclife]

Re: Paul Miller



I don't know him, but remember seeing his name in the old stack of Stereophiles...


A J.A. measurement excerpt from 2007:

https://www.stereophile.com/content/nagra-cdp-cd-player-measurements

View attachment 34479

Ah, I remember that now, was he the first to build or sell a jitter tester?

 

[AudioSceptic]

Here’s what their product page states:

“Classic PCM based DACS, including many of today’s DACS that can also process DSD, tend to cover up some of the subtle musical details buried deep within digital audio music; a problem inherent in their architecture. DirectStream solves this problem by employing a pure DSD single-bit approach for both PCM as well as DSD media. This means that your entire library of music can finally reveal all the music and subtle low-level details buried deep within its core.”

Hmm...

BWAHAHAHA!

 

[GrimSurfer]

Here’s what their product page states:

“Classic PCM based DACS, including many of today’s DACS that can also process DSD, tend to cover up some of the subtle musical details buried deep within digital audio music; a problem inherent in their architecture. DirectStream solves this problem by employing a pure DSD single-bit approach for both PCM as well as DSD media. This means that your entire library of music can finally reveal all the music and subtle low-level details buried deep within its core.”

Hmm...

I just love the qualifiers, which contain as much wiggle room as a politician's campaign promise. See my added bold italics.

I also love the undefined terms. See the underlined bits, which have a sickly sweet pang of snake oil to them.

 

[AudioSceptic]

Ah, I remember that now, was he the first to build or sell a jitter tester?

More here <https://www.hifinews.com/content/paul-miller>. He's devised a few innovations in audio measurement over the years.

 

[audimus]

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.

The above statement is the problem. If you want to make the assertion about what is below that very arbitrary level, that you can possibly hear it, that is just throwing FUD. To be valid in the methodology of science, you would need to document a few cases under rigorous listening testing that you could indeed hear something that is detrimental.

Here are the aditional problems when you dig deeper into the meaning of a single number that ranks it.

1. Equipment A and B rank the same in that number. One has higher harmonic distortion and lower noise while the other has higher noise level but lower harmonic distortion. Does that number mean they are necessarily equally bad and someone would hear that in both?

2. Or take a variant of the above case when equipment A is in the “pass” category in that arbitrary chop off and equipment B is below it. All of B’s numbers come from noise most of which is in the inaudible range with very little harmonic distortion. Most of A’s numbers come from harmonic distortion with a very low noise floor. Is it reasonable to say in the interests of science that A is a “pass” while B is a “fail”?

 

[AudioSceptic]

Thank you for your reviews Amir I had been thinking about PS audio gear and researching it for long time. I think Paul is a nice guy and I don't necessarily agree with everything he says but he can be insightful from time to time. With that said I don't trust companies that don't post the graphs just spouting off a bunch of numbers with no visual representation isn't enough for me to spend my hard earned money on a product. I guess I will hold on to my Benchmark DAC HGC 2 a little longer...

My pleasure. My impression of Paul is the same. He obviously has good historic and actual knowledge of audio. So many times what he describes are fine and correct. You just have to know the boundary of what is real science and what then becomes speculative stuff he talks about.

Are you talking about Paul Miller of Hi-Fi News and Miller Research? I thought that Icarus was talking about Paul McGowan of PS Audio.

 

[audimus]

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.

Except that choices in the real world aren’t that simple. Especially when you start using it to rank AVRs. One might say, it is a good goal for manufacturers to reach that level of perfection in their AVRs. That is easy for an armchair critic to say it as most of us here are with a few exceptions. It would be great if I could just go and buy 100mpg cars because the cost of fuel would be in the noise to worry about it (and there may be some that do reach that) but at what cost and compromise?

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

But your first statement above suggested just that. As did the post above yours. And that is what most people would do even here as well because the rest of the numbers don’t relate much to what they can expect in practice either unless yoh happen to be an audio professional.

And then some people (who have never built a device in their life to address market needs or know what is involved or even what the numbers mean) start to trash talk equipment and their manufacturers based on that ranking. How is that responsible for a site that professes to deal with science and scientific validity? Or how does that give credibility to these rankings (even with the reviews) for anyone outside the echo chamber?

 

[audimus]

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.

But you aren’t solving that problem either, just replacing it with “How much SINAD improvement will it take to lift that veil for my use”? 80db? 90db? 100db?

If cost was no problem, all of this would be moot. Even buy the highest rating you can afford is bad because that may lead to people spending more than what they need. That is like saying buy the highest HP car you can afford.

If someone had the resources to buy an Okto DAC, pair with Benchmark, all the decoding stuff that is needed to handle the home theater and somehow incorporate room correction etc, etc, sure no one would have to worry about noise or distortion but are they going to find it necessarily better than the $1500 AVR that measured poorly commensurate with the costs?

If not, then this has no more practical world use than the esoteric gear reviewers.

 

[audimus]

If your choice is to buy a $6k DAC to add some designer coloration to all the recordings, that's your choice. But don't claim that this is the best approach. It isn't when the same can be achieved with about 1/10th worth of equipment.

Non sequitur since no such claim of a best or better approach was claimed. This is about establishing the validity of these measurements for anything approaching real world needs.

This is the real world.
https://www.audiosciencereview.com/...ements-of-anthem-mrx-520-avr.8961/post-234463

 

[HammerSandwich]

Here’s what their product page states:
“...a problem inherent in their architecture. DirectStream solves this problem by employing a pure DSD single-bit approach for both PCM as well as DSD media."

To channel Bruno for a moment, they've made the mistake of specifying how, rather than what.

 

[audimus]

@audimus The DAC SINAD table in this thread is correlated to a DAC's ability to reproduce a signal equivalent to CD quality (16 bits or 96dB), a format that's been around for 30 years.

Consider that the oldest DAC measured is the Arcam Black Box 3, released around 1991, produces a SINAD of only 84dB and still outperforms the PS Audio DAC. The top range of the SINAD chart (>120dB) is correlated with the extremes of engineering quality, corresponding to a noise and distortion-free dynamic range that exceeds the limit of human hearing (there are nuances here to do with equal loudness curves and sensitivity).

Under many circumstances the distortions produced by the bottom range of DACs will be inaudible because of quiet listening volumes, noise floors of typical rooms and psychoacoustic masking. The distortions produced by DACs are also very minor compared to those of recording microphones and speakers.

Keeping that in mind, the way to understand the SINAD chart is, as the measured value increases, so does, generally speaking, the quality of engineering. This is not true in all cases and no engineer would tell you that a single number is sufficient to describe the functioning of a product. The important thing, really, is to use the chart as a reference. The reviews that Amir and others write help interpret measurements in terms of the functioning of the given unit, which can be deficient or excellent in certain physical areas (power supply, output stage, grounding, D/A conversion, filtering, routing, component selection and so on), or in terms of functioning (interface, overall build quality, connectivity) or price.

The point is that you can't know how well the product was put together without measuring it. ASR has shown conclusively that you can put together an excellent dedicated product for a very affordable price, and that the state-of-the-art is within reach.

I have no disagreements with anything you have said above. I have never said it is not worth measuring it. It is in the explicit and implied inferences drawn by any reasonable person where that measurement is being abused. The ranking table is nice and allows one an easily digestible number rather than glazing over all the charts and jargon that constitute tech-porn. But it is also implicitly overstating the meaning of that ranking.

To summarize my ramblings so far:
1. There is a gap between what the measurements are in answering the real market needs of average consumer not ones seeking engineering perfection regardless of costs where perfection itself becomes the goal.
2. Until that gap is bridged, these types of measurements will remain in the niche echo-domain of “perfection” seekers.
3. It creates unnecessary angst in owners of such units even if they (along with everyone of their peers in type of usage) are unable to hear anything detrimental from a lower ranked measurement (except in extreme cases) and have no interest in attaining perfection.
4. Trash-talking manufacturers just because something ranked low in some concocted number devoid of the context will not lead to an increasing number of manufacturers “seeing the light” especially in light of 2 above and so will remain ignored and at best treated as an annoyance.

There are steps that can be taken to start to address the above but that will have to come from people that more or less in sync with the above but not from an echo-chamber that circles the wagons in response.

I am going to stop here until the next series of trash-talking equipment starts.

 

[pkane]

Non sequitur since no such claim of a best or better approach was claimed. This is about establishing the validity of these measurements for anything approaching real world needs.

This is the real world.
https://www.audiosciencereview.com/...ements-of-anthem-mrx-520-avr.8961/post-234463

So what is your claim? Can you recommend something better than measurements, presumably backed up by some evidence?

MRX-520 is a good example of the need for measurements. Had they been done properly during design and testing, the AVR could have been a better audio device.

 

[617]

I'd be upset too if some nerd was trying to take food off my table and hawaiian shirts oh my kid's backs.

 

[Apesbrain]

I am going to stop here until the next series of trash-talking equipment starts.

https://en.wikipedia.org/wiki/Poisoning_the_well

 

[AudioSceptic]

I have no disagreements with anything you have said above. I have never said it is not worth measuring it. It is in the explicit and implied inferences drawn by any reasonable person where that measurement is being abused. The ranking table is nice and allows one an easily digestible number rather than glazing over all the charts and jargon that constitute tech-porn. But it is also implicitly overstating the meaning of that ranking.

To summarize my ramblings so far:
1. There is a gap between what the measurements are in answering the real market needs of average consumer not ones seeking engineering perfection regardless of costs where perfection itself becomes the goal.
2. Until that gap is bridged, these types of measurements will remain in the niche echo-domain of “perfection” seekers.
3. It creates unnecessary angst in owners of such units even if they (along with everyone of their peers in type of usage) are unable to hear anything detrimental from a lower ranked measurement (except in extreme cases) and have no interest in attaining perfection.
4. Trash-talking manufacturers just because something ranked low in some concocted number devoid of the context will not lead to an increasing number of manufacturers “seeing the light” especially in light of 2 above and so will remain ignored and at best treated as an annoyance.

There are steps that can be taken to start to address the above but that will have to come from people that more or less in sync with the above but not from an echo-chamber that circles the wagons in response.

I am going to stop here until the next series of trash-talking equipment starts.

To call it "trash-talking" is incorrect IMO. Over-hyped and over-priced components that do not reach even basic levels of performance (well below CD for DACs, let's say) yet claim to have some magic engineering that allows more musical detail to be heard than common stuff surely deserve to be ridiculed and exposed for what they are? I don't see people here rubbishing cheap gear that measures poorly or sensibly priced gear with adequate performance.

 

[mkawa]

i've surmised that most here aren't measurebators. currently, there are no metrics that can be used to generally describe products other than flowery language and/or dubious theoretical spec charts. this is more about finding glaring flaws and actually debugging some hardware as well as measuring how far the spec charts deviate from real product.

as an example, i've been using an smsl sanskrit 10th in my system for the last 6 months. it was followed by a 7498e based amplifier for the first 5 months and then a big boy amplifier from axiom audio the last month. after i switched to the axiom, i thought i noticed some weirdness, especially at the low-end, but it was subtle and i wasn't entirely sure which part of the chain was the issue. after seeing the amir's measurements of the sanskrit, i was able to target my debug; in fact, with my external power supply, usb was narrowly outresolving the new amplifier whereas spdif was not (a-hah moment!). even on usb, the measurements pointed out that the line output on the 10th (and all other smsl products btw) was very 'hot', and digging into the datasheets, reducing the volume reduced resolution significantly. hence, low-end distortion, and due to the dac.

i dug into the sofa for change and tried out a d50s and it resolved my issue in addition to sounding significantly better across the spectrum. without this data i'd still be a/bing random crap in my chain trying to figure out what the issue was.

further, i now know that the 10th will be fantastic via usb behind one my headphone amps.

bottom line: more and verifiable data is good! just use it wisely and don't shoot the messenger.

 

[LTig]

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.

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

But your first statement above suggested just that. As did the post above yours.

No. That's the only exception. If a unit is transparent under all circumstances (SINAD >= 120 dB) you can buy blind and need not worry. Regarding audibility better numbers will not make better sound, so you can choose among those units according to other criteria (price, features, look, ...).

But for units which are not transparent under all circumstances you must read the review.