Topic: DAC bits

[icebox]

Hi.  Pioneer CD players available here says 1 bit DAC and am seeing some NADs and HKs saying 24bit.  Does that mean 24 bits are 24x better than 1 bit?  or otherwise?

[rascal101]

The 1 bit DAC uses pulse width modulation. Meaning to say the depending on the relative amplitude of the analog signal the pulse width can be narrow or thick. Whereas with 24 bit, the max analog signal (normally around 2V) by 2^24 - when computed, this results in 0.12uV accuracy. Pictured another way this is similar with the number of pixels your computer screen has. The higher the number of bits the higher the number of pixels which results to a much more clearer picture.

With pulse with modulation, the limitation has to do with the propagation delays of the ICs and the accuracy of the crystal clock oscillator.

[icebox]

so can I conclude that 24 bit DAC CD players are 24x better than the 1 Bit DAC Pioneer CD players?

[rascal101]

It is not that simple because for higher order DACs the gating is the Vref (or voltage reference) while for 1 bit DACs the gating is the clock oscillator. I cannot say for certain % variance of the best Vref better than clock oscillator.

[johnrider999]

sir rascal, what about dvd players? is there any big difference using dvd player as your audio player? most dvd players are multi reader, and as we noticed dvd players are more cheaper compared to cdp eventhough they can read different discs. malaki ba talaga ang kaibahan ng tunog dvdp at cdp? gamit ko kasi now is pioneer dvdp, e2 rin gamit ko sa audios..

[edwin]

sir rascal, what about dvd players? is there any big difference using dvd player as your audio player? most dvd players are multi reader, and as we noticed dvd players are more cheaper compared to cdp eventhough they can read different discs. malaki ba talaga ang kaibahan ng tunog dvdp at cdp? gamit ko kasi now is pioneer dvdp, e2 rin gamit ko sa audios..

It will not always mean that a 24bit player will out do a 20 or even a lowly 18bit player. It will always boils down to the design.

DVD players use average components and do as much shortcut on the design. The audio signal is also being polluted by the video signal/circuitry.

[egzbuen]

DVD players use average components and do as much shortcut on the design. The audio signal is also being polluted by the video signal/circuitry.

Hi,

Newbie question. Does this mean that a CDP would always be better than a DVDP?

Let us say a Ganzlar DVDP compared to the entry level CDPs?

I ask since I will be purchasing my gears soon.

Thanks in advance 

[rascal101]

The DVD player is geared towards watching videos (and occassionally audio) whereas the CD player was geared specifically for hearing audio.

IMHO, for those entry or mid level DVDP, I would say yes it is likely that they sound little or no worse than the entry level CDP. Whereas high level DVDP would compete very well with entry and mid level CDP.

[Stagea]

I'd like to add that most gears that claim to have a "24-bit" or so DAC, actually have a 1-bit delta-sigma DAC running at a high speed and utilizing noise-shaping. This makes it possible for them to resolve the equivalent of 24-bit/192kHz for example, but this design is not 24-bit internally. The reason behind this is cost-driven for the most part.

CMIIW: As for Pioneer, most of their 1-bit DAC labelled CDPs don't do upsampling. They just oversample, typically at 8x. What complicates things is that their 24-bit labelled ones (usually utilizing TI/Burr Brown DACs) often also do not upsample afaik, but advertise the DAC's capability to handle the higher resolution (which obviously would not be realized with a redbook CD) to hype up the higher quality part. So 1-bit vs. 24-bit is their marketing speak for customers to know which models carry the higher grade DAC, but in reality both are 1-bit, and neither runs at 24-bit resolution.

I'm not singling-out Pioneer though. This truth-stretching is pretty common, especially for mass-market CE gear. They're not lying, but the advertised numbers often seem to be meant to mislead. That does not make their products bad, in fact CE offer very good value. It's just that the segment is so competitive, that they'd glitter the feature sheet with everything they could put. Of all the CDPs on the market (including more exalted brands) advertising 24-bit DACs (and they do have DACs capable of this), you'd only get a handful that actually do upsampling to 24-bit. Not that you'd gain a lot from upsampling, as we already know that we're still working with the same 16-bit/44kHz source (hence the following of NOS DACs), but it can be misleading nonetheless.