[csglinux]

Citations:

https://www.head-fi.org/threads/watts-up.800264/page-29#post-13820754

https://www.head-fi.org/threads/watts-up.800264/page-7#post-12520021

P.S. This one's important too: https://www.head-fi.org/threads/chord-hugo.702787/page-654#post-11368603

 

[bigshot]

the Dave is likely to be more faithfully reconstructing the original analog signal because of errors in the simpler filters in the iPhone DAC.

Measurable? Audible? That would show up as distortion, right? The distortion of the 6Splus seems to be well below the thresholds of audibility, so does it even matter? http://www.kenrockwell.com/apple/iphone-6s-plus-audio-quality.htm

 

[csglinux]

Measurable? Audible? That would show up as distortion, right? The distortion of the 6Splus seems to be well below the thresholds of audibility, so does it even matter? http://www.kenrockwell.com/apple/iphone-6s-plus-audio-quality.htm

If you're talking about standard measurements of THD+N from a high-amplitude 1 kHz sine wave - sure, but that involves nothing in the way of sharp transients. There are a zillion things that doesn't tell you about how it's going to perform with real music. I doubt Ken has the equipment to measure timing details to the precision in question.

 

[bigshot]

Then would it be audible in a blind A/B comparison?

By the way, this is what KR used to make those measurements. http://www.kenrockwell.com/audio/rohde-schwarz/upl.htm

 

[csglinux]

Then would it be audible in a blind A/B comparison?

By the way, this is what KR used to make those measurements. http://www.kenrockwell.com/audio/rohde-schwarz/upl.htm

I know Ken's work and I'm not bashing it. What he measures are important prerequisites. But he's not measuring anything other than sine waves. Would "it" be audible in a blind A/B? It's going to depend what "it" is. If you have even half-decent hearing, I'd be very surprised if you weren't able to pick out a Chord Dave from your iPhone in an SPL-matched blind A/B test of some real music. But obviously, only you could answer that question to your own satisfaction.

 

[bigshot]

If an iPhone measures in the basement with tones, the schmutz is going to be an order of magnitude more inaudible with music. Those specs look like they are completely inaudible to me.

I've done a controlled test between my iPhone and an Oppo HA-1 and I can't tell the difference with music. I have a Walmart DVD player and an Oppo BDP-103 that sounds exactly the same too. Is there any reason to believe that this DAC is likely to sound different? Or are we assuming it will just because of the sales pitch and vague technical talk?

It seems to me that if you want to say your DAC sounds better than your competitors, you aren't going to convince anyone if you don't provide specs or listening tests to prove it. At least prove that there is a difference.

 

[csglinux]

If an iPhone measures in the basement with tones, the schmutz is going to be an order of magnitude more inaudible with music.

No. Single sine-wave tones can easily mask noise floors and they cannot suffer timing errors as you have no transients.

 

[csglinux]

It seems to me that if you want to say your DAC sounds better than your competitors, you aren't going to convince anyone if you don't provide specs.

Check the specs of the Dave. It is off the chart in terms of zeros after the decimal point.

 

[bigshot]

Look at the threshold of audibility to the human ear then and how it compares. Every piece of electronic audio equipment I've owned since the late 80s has been audibly transparent. I haven't gone out of my way or spent a lot of money on all of it, but all of it performs the same. My speakers and headphones all sound different. That I understand. But transparent digital players and amps aren't that hard to make. You either have to do a really bad job of design, or deliberately color them to make them sound different. I don't want them to sound different. I've carefully EQed my system and I want the sources and amps to all sound the same- calibrated to audible transparency. If they aren't that, I would return them. But I haven't found one yet that needs to be returned.

 

[csglinux]

Look at the threshold of audibility to the human ear then and how it compares.

How it compares to what? What are you even trying to say here? This is supposed to be a sound science forum. Look, I hate to be dismissive, but posts like this belong in the unsubstantiated opinions forum. Nobody is learning anything from this.

I'm sure you know as well as I do what the thresholds are with respect to frequency and what the thresholds may or may not be (according to some neuroscientists) with respect to transient resolution. Forgive me in advance if I don't respond to further posts like this, but this is going nowhere and life is just too short.

 

[Arpiben]

@csglinux

Timing resolution, timing accuracy, residual jitter are quite easy to define, measure or estimate.
Unfortunately, DAC manufacturers when asked rarely provide answers and prefer going round in circles.

 

[old tech]

@csglinux

Timing resolution, timing accuracy, residual jitter are quite easy to define, measure or estimate.
Unfortunately, DAC manufacturers when asked rarely provide answers and prefer going round in circles.

Perhaps that is because such measurements are so small that it is academic, given their inaudibility?

 

[bigshot]

How it compares to what? What are you even trying to say here?

I'm asking how the specs compare to the research that establishes the thresholds of perception for discerning differences when listening to music under normal conditions. You should be able to look at measurements and relate them to how they will be perceived by the end user. That's science too.

There is a certain point where differences can no longer be detected with human ears. That is the point of transparency. There's a certain amount of play there, but if the specs are below the established threshold by an order of magnitude, it should be pretty safe to predict that a difference can't be heard.

Do you know the specs for the human ear?

@csglinux Timing resolution, timing accuracy, residual jitter are quite easy to define, measure or estimate. Unfortunately, DAC manufacturers when asked rarely provide answers and prefer going round in circles.

Oh! That is very simple. You just take something you know is transparent and do a controlled listening test to discover whether a difference between that and what you're testing can be perceived. If there's no audible difference, then it's transparent too.

Numbers on a page are great in theory. But the rubber meets the road with the thresholds of human hearing.

A nod is as good as a wink to a blind bat.

 

[bigshot]

One more quick thing... If I haven't been able to discern any difference between players since the late 80s and I've heard a wide variety of different units, from $40 Walmart Chinese DVD players to a dozen or more Apple products to the best equipment Oppo makes to good players by Sony, Philips and Pioneer, why should I spend thousands of dollars on something with no published specs, no independent listening tests that show it's superior and a whole bunch of sales pitch that appears to be a blend of real science and hot air?

I am willing to call bluffs on the difference between lossy and lossless by sharing a comparison test with anyone who is interested in finding out the truth. If there is a DAC that really is an improvement on all of the identical players I've heard, someone can lend it to me for a couple of weeks secure in the knowledge that I'll give it a fair shot and I'll do a careful comparison. When there's no solid facts to back up claims, I'm under no obligation to believe any of it. If someone wants to offer me a "put up or shut up" I'm game for it and I will honestly report my results.

 

[gregorio]

[1] As your example (violin section), you've chosen an instrument with one of the slowest attacks,
[2] and then you've vastly overestimated the effects of viscous dissipation on acoustic waves...

1. Would you prefer if I'd used violas, cellos or basses, how about wind instruments? The fastest attacks are from struck (percussion) instruments but then percussion instruments are typically placed at the back of a music ensemble and when close mic'ed, are typically processed to significantly change the transients.
2. No I haven't. Using your 100m example, 20kHz air absorption would be about 52dB! Note to others, this is just air absorption of high frequencies and not related to loss of energy due to distance (roughly defined by the inverse square law) which would need to be added to the air absorption figures if we wanted to calculate total attenuation over distance, however, for this argument we can ignore the inverse square law because it affects all freqs equally. By way of comparison, 30kHz at 100m would be attenuated by air by about 94dB, 5kH by about 4dB and 500Hz about 0.3dB. The shape/freq content of a transient is therefore significantly changed by air absorption. Obviously, 100m is a bit extreme but on the other hand, in the real world we're not just talking about air absorption of high freqs, there are other materials (walls, floors, furniture and of course people, musicians and audience) which absorb high freqs many times more effectively than air.

The point I was making is that attack transients of acoustic instruments contain a wider freq content than the note itself (the sustain portion of the ADSR envelope) and change significantly in the real world, to the point of disappearing entirely. If we take another, completely different example, say a flute. At close range, you'll hear an attack which includes considerable high freq hiss, the sound of the air itself being blown by the musician across the flute's mouthpiece and this attack is fairly explosive as it's typically created by trapping and suddenly releasing air, similar to saying "Ta". At a normal listening distance in a performance environment this transient mostly disappears and we just hear relatively smooth notes. The same is true with all wind instruments and with the human voice itself (speaking or singing), where we have close proximity transients which we do not perceive at any normal listening distance. Specifically attacks/transients called plosives and essing, caused by the pronunciation of letters such as P, B, K/C, S, T and others, as any experienced recording engineer knows well, as close mic'ing the human voice typically requires significant processing of the transients.

I'm using the above and what I've stated previously to explain that transients are massively variable, to the point of virtually disappearing completely in some real life performance situations, to counter Watt's assertion that timbre and pitch is dependent on transients. If we listen to a violin section (or flute or whatever) playing a note from say the back of a concert hall 100m away and we've completely lost the transients, are we unable to discern the pitch of that note or even that it is a violin section? Admittedly, getting a seat at the back of the concert hall is not the best place to be but why would anyone ever buy a seat at the back of a concert hall if they couldn't discern timbre and therefore tell what instruments are playing (or even that they are musical instruments), what notes (pitches) they're playing or when the musicians start or stop playing them? In addition to the obvious nonsense of Watt's claims regarding pitch and timbre being dependent on transients, we've also got the issue of Watt's claims about transients and sound stage, which are potentially somewhat more valid but certainly not to the extent Watt's is making out. Again, we can remove all the transients from various sounds and instruments and still create a soundstage and transients are smeared in time by real life acoustics or signal processing of closely miced instruments, so it's hard to see what his 4us has to do with anything in a real life music mix, regardless of whether he's on about transient duration, rise times or delay?

G