- Going to 32x PCM (1536kHz) would have made this truly the ultimate HQPlayer NAA endpoint. I wonder if there's a hardware limitation on the PCM output rate? Maybe the USB will still go this high...
Agree with your shared thoughts, with exception of the last statement (copied above...);
Most 'upper' (TOP!) frequencies that a DAC chip offers are usually with diminished capability (when we look at their 'white sheet' docs); and given implemented circuits seldom deliver more/equal to a DAC chips 'white sheet' spec; the top most supported frequencies simply give me an indication as to which frequencies might still deliver 'product excellence'.
It is one thing to support a given bitrate or sampling frequency, (and that nets sales from eager consumers wanting to buy 'the next big thing') - but chasing ones tail for esoteric formats that are unlikely to see much use isn't of much worth/'true value' to end consumers..
Far better off easing the burden on your upsampling hardware, and giving the cable a more reasonable bandwidth to push.. the resultant sound by easing off 'one notch' is generally better realised music.
Some circuits DO push past the white sheet values for the DAC chip (iFi do so notably, for example the iFi Diablo clearly does so.. ); but I wouldn't be seeking 1536khz sampling rates from an older BurrBrown DAC chip (a chip built for music rather than 'bragging rights' rates and supporting of unadopted consumer formats etc)..
And if iFi jumped to ESS designs then they would lose me as a customer overnight.
And I am not directly picking on an ESS chipset here with this statement (heaven forbid!), but rather that iFi had a handful of great engineers (or at least several fingers worth of them..) back when they came up with circuits that could push this BurrBrown DAC chip well past its 'theoretical' specs..
Clever implementation is everything in audio, and it constantly amazes me how much an iFi Diablo
smokes a Topping D90 for sound output quality.
Maybe some aspect of the Diablo is using a 'class A' output stage (the D90s' biggest weakness to my ears), but it clearly is in their 'multibit' (top six bits) approach that gives detail and definition where it counts, on top of 'top tier specs' beyond what any given consumers system is likely to resolve.
If chasing 1536khz (or 3072khz etc..) is the goal, then 'yes' - some super new DAC chip will be needed.
Just be aware that for approx fifteen years the market for consumer audio has been 'portable' and not home hifi (most surround amps use 'mid tier' DAC chips and are happy with older designs), and so most modern DAC chips are designed to 'sip power' (or give pin outs for I/V stages for configurability to vary their implementation); and chasing future format numbers and rates seems the intent.
Not saying the latest DAC chips are poor, but that as is (un)common knowledge- a DAC is the whole circuit and not just the chip.
iFi have
mastered a specific chip, and this fact is of a tangible benefit to us actual end users wanting musicality.
If we consider that two years of R&D was lost by a few manufacturers attempting to design to utilise the AKM449X parts, and then had to throw away that circuit tuning nearly overnight to make use of what the market could supply them, I wouldn't hesitate to predict that the next couple of years will bring a lot of reviews to popular press where industry professionals can RIGHTLY state 'improved implementation over last years/early versions' more so for the ESS chipsets than any other...
As someone who bought (and sold) a lot of PC sound cards in the early nineties, seeing well specced cards 'sound like digital' and vastly more musical cards that didn't 'chase numbers'- I learned early in the game that spec sheets can reveal aspects of the circuit, sure; but certainly not 'musicality' of the design.
Sure the D90 is a great specc'd DAC- but I reiterate- an iFI Diablo smokes it....