Because you can compare, measure (test) in/out of electronics without music.
Why does almost any objective test bother some so much?
To clarify the suggestion about the R and L was to take an ordinary power resistor and a small length of wire that exactly equal the Bybee and do a comparison, sorry, ears only. I realize now that this would require a panel of expert listeners rigidly following something like the ITU spec, which will never happen.
They (DAC shills) may have done it in private setting. Yes, they want privacy on certain audio info.
To Bob's point about listening for accuracy, Jam has strong opinions about what is right (what we should be aiming for) in reproduction. #1 on Jam's list is much like what Bonsai described listening to his good phono setup: the stereo illusion of a sound stage extending between and laterally beyond the speakers, with apparent localization of instruments and vocals distributed along the sound stage from left to right. If one can sense location of the speakers with eyes closed (point at the center of each one using ears only), that is considered a significant flaw. The Topping dac did very well in that regard using the big Sound Lab electrostat speakers and Benchmark AHB2. How well the AK4499 eval board does in that subjective test is very dependent on which clocks I use with it. So far, best results are with 22/24MHz Crystek 957 modules.
Bad news is even a cheap **** DAC can pull off that trick with half decent speakers and a non-pathalogical room.
DAC-3 does it, but does so very differently from D90. DAC-3 sound stage is much more compressed laterally towards the middle and pushed forward towards the listener. All perceptually speaking, of course.
When I have listened to cheap dacs doing it, the width of a lateral location where an instrument or vocal is positioned becomes wider. It is like a singer's mouth one meter wide, or maybe one foot wide. As it narrows down to a pinpoint, other things usually start to improve too.
In other words, there are details to how well it is done. And of course, that is only item #1.
My cheap phono does it. The equivalent of jitter here is orders of magnitude worse than any DAC. Recently playing "Space is the Place" by Sun Ra it was very evident.
Pin point imagining isn't DAC related it's room acoustics plus loudspeakers related. It's created from a lack of early reflections Vs the direct sound over the frequencies necessary for image creation. Introduce early reflections and you end up with a smeared/wider central image and a haze of high frequency mush diluting the rest of the soundstage accuracy.
I mean the DAC could affect the pin point central image if you swapped from one with a flat frequency response to one without. Also of you weren't level matched between DACs or if you were listening to one DAC before lunch another the other one after lunch.
I mean the DAC could affect the pin point central image if you swapped from one with a flat frequency response to one without. Also of you weren't level matched between DACs or if you were listening to one DAC before lunch another the other one after lunch.
Okay. There is no way to explain with subjective words, only with numbers and by using measuring instruments. Got it.
Can you explain to me how a DAC that displays 0.00008% distortion at 0dBfs sounds less distorted with an FPGA attenuating the signal fed to it by 3dB prior?
Not to mention that the D90 uses digital attention for all it's volume adjustments. The only time this would ever have an impact on the full scale output is if you had the volume control turned up to higher than -3dB. Which almost no one will do when using the devices internal volume control. So in other words it really sounds no different. Especially if you're listening significantly below having the volume set to -3dB. I reckon most people will be listening at -30 to -40dB so even less chance of that making a difference. Unless you're saying the digital front end of the AK4499 doesn't like having its MSBs written to a particular state. The DAC itself isn't going to see any difference, between the FPGA + AK4499 setting the volume, or the AK4499 doing it all, as its internal volume control precedes the modulator.
Read the manual. D90 has a 'dac' mode which disables volume control. Runs full up (for it, which is about -3dBFS for AK4499, measure it at the I/V opamp output pins yourself if you want ).
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Actually no, I used subjective words to describe the perceived effects on the soundstage by changes in the measurable directivity.
What you're doing is using subjective words to describe something that you can't explain via measurements. Or haven't tried to. But as far as I remember it was cheap DAC smears the soundstage and expensive one does not. What is it exactly that makes a DAC cheap, how cheap is cheap? And what aspect of its cheapness effects it's measured performance in such a way that it would have the affect on the soundstage that you're describing?
It sounds like you're implying jitter but a clock doesn't have to be expensive to display very low levels of jitter.
You can't win this argument. I've sat with folks (fellows of the AES and IEEE who were doing digital audio before CD) and listened to demos of stereo parlor tricks moving images around with simple but large phase and amplitude manipulations, you could literally make a vocal go around your head 360 degrees with one pot. There is no manifestation of jitter at the level of even an ordinary crystal that can do the same. This is simply an extraordinary claim with absolutely no basis in reality.
The claims of improvement of a DAC with some super clock has no more weight to me than the guy that prefers his $90 T amp to a $2000 class A amp. They are both preferences based on a complex personal reality that is owned by them alone.
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I have a cheap DAC which doesn't 'smear the soundstage'. BOM cost under $10 using mainly recycled parts from Taobao.
Level mismatch and listening position variation would do that. Try it yourself by using the same DAC but vary those two aspects.
I fully believe your experience here. The problem is that with an other room and other speakers, the finding may be reversed. Agreed?
So how does one choose a DAC?
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Excellence example of perception bias caused by price, thank you for posting something on topic.