What's an example of a "good DAC"?
Nov 16, 2017 at 10:00 PM Post #301 of 412

sonitus mirus

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Well, my KSE1500 DAC definitely sounds different from my external DAC - and that's very easy to do an SPL-matched A/B with, because you can just switch from the line-in to a flat EQ, which flips on the internal DAC. But I hear you - I'll admit the differences are small. With the Dave, the differences I heard were more significant, but it's the whole package here because Dave is not just a DAC - at least I didn't test it with the KSE1500's line-in. My tests were done with Focal Utopias, which also used the Dave's amp.

I don't own a Dave. I'm not planning on buying a Dave. I'm not trying to push Chord products. I'm simply suggesting listening to the Dave - and A/Bing against your existing DAC(s). If you hear no difference, you'll have just saved yourself $13,500 + tax + shipping.

I'm certain I could find some speakers that cost a fraction of that $13,500 that would make an improved difference that even I could hear and measure. A DAC is the last piece of gear I would search for to make any improvement with my system. What difference is being heard with the Dave? If it can be demonstrated to be something that can be reliably heard, it would be measurable. What's the difference with the Dave that makes it sound better? Are there any repeatable listening tests that remove the most basic biases showing people can hear a difference?
 
Nov 16, 2017 at 10:17 PM Post #302 of 412

bigshot

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What's your reference point for the most perfect-sounding DAC, against which anything else (even if it seemingly sounds better) must be an aberration?

I'll answer... For me it's a string of Apple computers, iPods and iPhones, Oppo BDP-103 and HA-1, a high end Philips SACD/DVD player from the heyday of SACD, the DAC in my Yamaha AVR, blu-ray players by Sony and Pioneer, DVD players by Sony and a $49 Walmart special from China and a Mac based ProTools workstation. All of those sound identical to me.

I probably spend $13,000 on media every two or three years. I'd prefer that to another DAC that sounds the same.
 
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Nov 16, 2017 at 10:17 PM Post #303 of 412

csglinux

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Well, DACs and cables are almost always pretty terrible value-for-money audio upgrades. I have no idea what the difference is with Dave that made it sound better to my ears. That's why I posted here. I'm fascinated to find out.
 
Nov 16, 2017 at 10:19 PM Post #304 of 412

csglinux

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I'll answer... For me it's a string of Apple computers, iPods and iPhones, Oppo BDP-103 and HA-1, a high end Philips SACD/DVD player from the heyday of SACD, the DAC in my Yamaha AVR, blu-ray players by Sony and Pioneer, DVD players by Sony and a $49 Walmart special from China and a Mac based ProTools workstation. All of those sound identical to me.
You are one lucky guy :) Let's hope you find the exact same experience with the Dave.
 
Nov 17, 2017 at 12:37 AM Post #308 of 412

old tech

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What's your reference point for the most perfect-sounding DAC, against which anything else (even if it seemingly sounds better) must be an aberration?
This is the part I don't understand about DACs or your rebuttal of Gregorio. At the end of the day a DAC processes an electrical signal and outputs an electrical signal. The out electrical signal can be compared to an original benchmark, say the original signal that went into the ADC earlier in a production chain. The two can be compared and nulled.

Given that, the DAC that outputs a signal that is perfect, or as perfect as can be within the domain of human hearing capability, must by definition be at the highest level of fidelity. If most DACs are already at this level of transparency already achieve this, how would a mega dollar DAC be more higher fidelity? How is the subject of neuroscience even relevant when it relates to fidelity to the original source? Once upon a time I did dapple in high end DACs and sure, many of them did sound different to a generic Wolfson or Burr Brown implementation (when it could be demonstrated under a DBX not to be placebo) but is that due to higher fidelity or a choice by the manufacturer to put a euphonic signature sound above fidelity? Is it being suggested that neuroscience suggests the human brain process the euphony in a way that is better than true high fidelity? If so that raises two issues - as euphony is subjective to an individual how do we know what is the best euphony for human brains? More fundamentally, if euphony is that important and subjectively ubiquitous across individuals why wouldn't the recording be mixed and mastered that way while maintaining transparent high fidelity in the playback chain, including transparent, low cost commoditised DACs?
 
Nov 17, 2017 at 1:06 AM Post #309 of 412

csglinux

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The short answer is I don't know, and we may never find out, because the inner workings of Chord's WTA filters aren't explained in any detail.

I'm guessing - and this is pure supposition - that they're doing something creative or artful beyond the Nyquist frequency. Both Rob Watts and the Meridian guys keep going on about transients and quoting this 4 microsecond scale. They're coming at this from different angles, but it seems they're both somehow trying to sneak in a steeper/sharper gradient than you could normally get from 2/f. (Update. No - I was wrong in this supposition!) In MQA they apparently sacrifice the odd bit to gain a local improvement in temporal resolution - which they can do through having operated on a higher sample rate to begin with. I don't know what Rob Watts is doing with 44/16 FLAC. Creating an artificially-steep(er) transient from CD data seems kind of sketchy - because what if the attack transient time really was 1/f and you artificially sharpen it further?

Otherwise, I have no idea where this 4 microsecond scale enters the picture.
 
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Nov 17, 2017 at 1:26 AM Post #310 of 412

JaeYoon

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Thank goodness I'm not an audiophile and don't lose sleep or worry about those things.
I have to applaud robb watts dedication.

But I'm good with what I have now. I also listen to the music more so than think about my equipment.
 
Nov 17, 2017 at 3:49 AM Post #311 of 412

gregorio

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However, I tend to lean towards Rob's point that current neuroscience and our understanding of intelligence and audio processing is in its infancy.
Slide 3. Each sound might be separated out by the brain - if you're concentrating on it. You and Rob seem to be in agreement here.
Slide 4. It seems perfectly reasonable to require some margin of safety.
Slide 5. In all music (except perhaps electronic music), the ADSR (attack, decay, sustain, release) is exactly what helps us distnguish one instrument from another. This is how synthesizers trick the brain into thinking a keyboard is actually a trumpet. I don't deny there are overtones that affect overall timbre, but these aren't that relevant for short, staccato hemidemisemiquavers where there is very little time for the brain to process them.
Slide 6. Imagine I'm on a chromatic run with (for whatever reason) no transients at all in the reproduction of my notes - i.e., I'm slowly fuzzing from one note to the next. (Not because I'm not an outstanding bass player, but because of a poor digital reproduction.) At any point in time between me playing an E and a G, the pitch of the reproduced note is anywhere between 83.4 Hz and ~98 Hz. Are you hearing the start of the G, or a 87.3 Hz F, or a 92.5 Hz F#? I can see what he might be alluding to. Without a clear start/stop of each note, all you have is a continuous shift in pitch.
Slide 7. Rob is absolutely right on this one. ADSR.
Slide 8. First four points I agree with completely. Pitch and timbre we've covered already. Starting and stopping is obvious (you're not really calling that a lie, are you?!). Yep - he's right about soundstage too - the timing differences reaching the left and right ear are a crucial part of what allow us to place sounds in 3D space. As for the last 4 points - well, I'm not a neuroscientist, but we agreed to roll with the 4 microseconds, right? "Very small" and "very big" can be subjective, so this isn't necessarily wrong. You then say "Timing accuracy between channels is perfect at 44.1, there is zero relative shift!" If we're dealing with sound that doesn't reach the left and right ears at the exact same time, then we'd better have a relative shift, or we'll have unphysically altered the soundstage. I believe what Rob is shooting for is a consistent reproduction of the timing (to L and R channels) from a given source (but the details he gives are hazy - see my later comment on this).
[9] I'm sure we all appreciate Dirac delta functions don't usually exist in music. But what if I were to record a percussive instrument like a snare - or maybe even a blast wave on my next album? To all intents and purposes, these are like the initial spike of the dirac delta to a 44 kHz sampling rate. I would absolutely want a DAC that could take care of these extreme cases, even if I only spent most of my time listening to something with a slower attack, like piano.

I don't disagree that we have limited understanding of how the brain creates perception. However Rob Watts quoted a figure of 90% of what we perceive is created by the brain, made various claims about how the brain perceives sound and then said we have "no understanding" of how the brain processes the ears data, thereby making a lie of all the claims.
Slide 3: No, there is some separation but it's rather limited. Are you saying that when you listen to a symphony orchestra you can separate all the 18 or so individual violins during a tutti section, even if you concentrate solely on the violins? If not, then the brain cannot "separate each sound".
Slide 4: But how much is "some"? Is a thousand or more times below audibility not enough? Neurons firing with a resolution of 4um does not necessarily imply that's the resolution the brain can hear, it also does not indicate the brain samples at 250kHz. In fact, if we take his previous figure of the brain only using 10% of the data it receives, then only 1 in 10 of those neuron impulses is processed, implying a resolution more like 40um.
Slide 5: Exactly, but transients only account for the A of the ADSR! And, the Attack contributes to the sound/timbre of an instrument only to a very limited degree, for example the attack of brass instruments is very similar, what happens in the Sustain part of the envelope plays a larger part in differentiating say a french horn from a trumpet. Also, even hemi-demi-semi quavers still have a duration of many milli-seconds, not micro-secs!
Slide 6: Transients have virtually no impact on the detection of pitch. It's mainly the fundamental and harmonics, of the sustain portion of the sound envelope. It's not difficult to test for yourself; take a note and cut off the transient. Listen to that transient and see if you can determine pitch, listen to the sustain without the transient and try again. Notes blending into each other is a function of performance, the resonance/s of the instrument and the acoustics, digital accuracy is way beyond any of these factors.
Slide 7: But Rob Watts is not saying ADSR, he's effectively saying timbre depends on A (Attack)!
Slide 8: I do NOT agree with the first 4 points: We do NOT perceive pitch from transients. Transients play a part in soundstage but only a part, in 3D space reflections are vital. Transients play a limited part in timbre. The last of the four points is rather vague but is not entirely/always true. The last 4 points seem more ridiculous: I'm not sure the 4um is an accurate figure and it's not clear what he means by timing resolution. If he's talking about jitter, CD is down in the tens of pico secs, a hundred thousand times or so below even his 4um detection. If he's talking about timing inaccuracy between left and right channels, there is none on CD. How does a hundred thousand times below the 4us he quotes and no timing error between left and right channels have any impact at all, let alone a "big impact"?
9. No. A mic capsule has mass, it cannot respond instantaneously, same with the reproduction transducer, same with ear drum and then we've also got air and materials absorption. Regardless of what say a snare drum rimshot actually produces, what you are actually going to hear is already highly distorted, even with no digital conversion in the chain (for example, mic preamp output direct to speaker amplifier). Not to mention that a rimshot is not just an initial transient!

G
 
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Nov 17, 2017 at 9:32 AM Post #312 of 412

TheTrace

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I'm certain I could find some speakers that cost a fraction of that $13,500 that would make an improved difference that even I could hear and measure. A DAC is the last piece I of gear I would search for to make any improvement with my system. What difference is being heard with the Dave? If it can be demonstrated to be something that can be reliably heard, it would be measurable. What's the difference with the Dave that makes it sound better? Are there any repeatable listening tests that remove the most basic biases showing people can hear a difference?
Well, DACs and cables are almost always pretty terrible value-for-money audio upgrades. I have no idea what the difference is with Dave that made it sound better to my ears. That's why I posted here. I'm fascinated to find out.
I'm interested in finding the answer to this too. I wonder if it's something else inside the unit that makes performance "better" to ones ears like an amp, filter, processor or the "timing" that they rave about. I have absolutely no knowledge on this to even provide an educated guess, I'm at the beginning of my studies (a year and change) in audio engineering if that provides any perspective.

I just find it interesting that I have this experience with even the Mojo. In my car (which has an amp for the 4 aftermarket speakers and an amp for the sub) there's a noticeable increase in quality versus just my smartphone (Axon 7). I would like to know why that is, whether the Mojo's amp that drives everything better with more power (I was told double amping was a bad thing though..), if it's my phone's output that's lacking, or it's something else in the device that causes it.
 
Nov 17, 2017 at 9:57 AM Post #313 of 412

Whazzzup

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there is no way id spend dave monies. Course not that i have not maxed the middle market, but thats bye choice and very happy. I have not churned my gear, don't even care about additions. Just like the fact that some manufacturer is always trying and existing are forced to respond, proactively ....Course that is on all components not just dacs, so just find it fun and interesting.
 
Nov 17, 2017 at 10:14 AM Post #314 of 412

bigshot

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I heard they have a solid gold iPhone too!
 
Nov 20, 2017 at 5:22 PM Post #315 of 412

reginalb

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If I had a pair of headphones that required more juice than what my phone can pump out I'd be tempted to drive them with a Chord Mojo. But mainly because it looks like a spaceship and it's not as expensive as the other offerings from Chord. What are we talking about again?

The short answer is I don't know, and we may never find out, because the inner workings of Chord's WTA filters aren't explained in any detail.

I'm guessing - and this is pure supposition - that they're doing something creative or artful beyond the Nyquist frequency. Both Rob Watts and the Meridian guys keep going on about transients and quoting this 4 microsecond scale. They're coming at this from different angles, but it seems they're both somehow trying to sneak in a steeper/sharper gradient than you could normally get from 1/f. In MQA they apparently sacrifice the odd bit to gain a local improvement in temporal resolution - which they can do through having operated on a higher sample rate to begin with. I don't know what Rob Watts is doing with 44/16 FLAC. Creating an artificially-steep(er) transient from CD data seems kind of sketchy - because what if the attack transient time really was 1/f and you artificially sharpen it further?

Otherwise, I have no idea where this 4 microsecond scale enters the picture.

The question is, should your DAC do anything other than faithfully transform the digital signal it receives back to the original waveform that was handed to the ADC? If we take the job of the DAC to be strictly conversion from the digital realm in to the analog, then you would have to say: No. That's not the job of the DAC. If you agree the job of a DAC is to faithfully turn the digital signal back in to its original analog waveform, then anything "artful" is also incorrect. But if you can afford the Dave, and you like the Dave, then rock that thing.

I've wondered at the claims they make over there in the chord camp, they're obsessed with temporal resolution. I suspect that the guys over at Schiit would explain to you why that was a bunch of hooey, and that super expensive DAC's are really silly. Then they'll try to sell your their $2,300 "Multi-bit" DAC. I love that about Schiit, they'll talk all day long about not wasting your money, then sell a $2,300 DAC. LOL

Anyway, I'm off track, I'd gladly demo a Chord, but won't be buying one. They do look cool, though, in my opinion. All the companies seem to have their own secret sauce that is the secret to audio nirvana. Remember when it was a severe treble roll for HiFiMan? Good times.
 
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