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16 bit vs 24 bit vs 35 bit vs 36 bit vs 64 bit DAC sampling

I have limited knowledge about DAC's, but as I understand it, a typical CD player used to have 16 bit sampling, and supposedly no one was supposed to be able to hear the difference between anything more than 16 bit sampling; however, I recently purchased an Esoteric K-01X, which has 35 bit sampling (why 35 bits? no doubt only to differentiate it from their then top of the line 36 bit sampled Grandioso series).  

Now I can hear a big difference between my old Musical Fidelity kW DM25 DAC with 24 bit sampling (circa 2005), and the newer Esoteric DAC with 35 bit sampling, although I'm not supposed to, although maybe there are some other electrical programs playing with the sound besides the sampling rate.  

Now, there are 64 bit sampling DAC's, and I'm wondering how much the ear actually does hear from the sampling, or if it's something else entirely that's making the digital sound better?  

Any insightful opinions or perspectives?  

Thanks.
drbond

Showing 8 responses by drbond

drbond OP
396 posts
 

An audiophile friend gave me a book for Christmas, written by Robert Harley, "The Complete Guide to High-End Audio".  The quote below, which explains what I hear quite adeptly, is from that book, pg 231, from the section titled, :"16 Bits, 20Bits, 24 Bits":

"...the benefits of the increase in word length from 16 to 18, 20, and even 24 bits are not in dispute.  As I mentioned earlier, word length is the number of bits used to encode the audio signal's amplitude at each sample. Assigning a number--called a word--to represent the audio signal's amplitude is called quantization.  The word length determines the system's resolution, dynamic range, distortion, and signal/noise ratio.  We also call the word length resolution. . .

....the greater the number of bits in each digital word, the more precisely the analog signal's amplitude is encoded. . . The longer the quantization word, the more steps, and thus the finer the resolution.  

. . . .the resolution of a digital audio signal isn't defined by the maximum number of bits available, but the by the number of bits being used at any given moment.  

The advent of 20- and 24-bit digital audio not only expands the dynamic range, but also increases the resolution of low-level detail.  This low-level detail can be fine nuances of an instrument's timbre, which enhance the sense of realism.  It can also be subtle spatial cues, such as discrete  acoustic reflections and reverberation decay, which the ear interprets as a more convincing reprodution of the original recording venue. 

Longer word lengths also contribute to better sound because the postproduction (mixing, equalization, signal processing) common in the recording or mastering studio can be performed with much greater mathematical precision.  Moreover, any noise added by these processes is spread out over a wider bandwidth, which makes it less audible.

The combination of higher sampling rate and longer word length results in greatly improved sound quality.  (A digital system's resolution can also be increased by adding to the signal a small amount of noise, called dither...)"

He then proceeds to outline the limitations of 20+bit processing, often calling the additional bits, simply marketing bits, fi they're not done right, and that for most systems any information over 20 bits is "rarely capable of delivering real audio information"

So, I needless to say, it appears simple, but it quickly becomes a complex issue. 

drbond OP
396 posts
 
@jasonbourne52

The manufacturers seem to indicate in their literature that the bit sampling is how much the digital steps from the signal are smoothened to sound more analog.  
drbond OP
396 posts
 
@jasonbourne52

Well, around the same time I plugged in my new Esoteric K-01X and started playing it, with 35 bit sampling, a rabid bat did attack a man in my county!
drbond OP
396 posts
 
@djones51

So, most of the markedly improved sound that I hear is from the improved transport stability, and more precise laser reading, and not from the 35 bit sampling?  There must be some other software aspect to the improved sound as well. . .
drbond OP
396 posts
 
@audioman58 

If 20 bits is all that is possible, why are the engineers chasing the bit rate higher to 64 bit rate now?  I suppose there's alot of people who don't understand what they are doing with the bit rate?  Maybe this is this akin to selling the $4,000 XLR cable when the $60 cable is as accurate as you'll get. . . 

So it's the other features of the unit that make it sound so much better?  I suppose it's the transport, the power supply, the more accurate clock, the high slew rate, large current, and digital filters that are playing the larger role of improving the sound quality.   

Here is the ad from the Esoteric K-01X features page:

35 bit D/A Processing

The K-01X combines multiple 32-bit DAC chipsets and utilizes 35-bit D/A processing algorithm to convert the PCM signal to analog at a high resolution in excess of 32 bits. 35-bit processing achieves an astounding resolution that is fully 2,048 times that of 24-bit processing. In the digital range, full advantage is taken of high-bit data gradation to minimize calculation errors and provide faithful conversion to analog, thereby attaining outstanding powers of expression with even extremely small music signals.
drbond OP
396 posts
 
@audioman58

Your recommended article seems to explain much about the discussion. The article does immediate clarify one thing that I have noticed: older late 1950’s recordings sound much quieter and clearer on the Esoteric with the much higher bit sampling than it did on the Musical Fidelity with the 24 bit sampling.

Here is the summary from one part:

"So why on Earth would they even create a digital recording format that can’t even be listened to?!?!?!?!?

Simple: bit-depths and sampling rates far above the range of human hearing are used during the recording, editing, mixing, and mastering processes to lower digital noise in audible spectrum when recordings are downsampled to the significantly lower resolution sold in commercially released recordings."


...so, during the down-sampling process of the signal in the DAC, that 35 bit analysis is making some recordings sound much better. . .

However, in the same article, the discussion about the power supply is quite interesting, and how a very quiet power supply would be needed to sample above 20 bits. . .
drbond OP
396 posts
 
@alan60 

I hope this doesn't turn into a "this is better" or "that is better" thread, but I have listened to a high end dCS SACD player in my system before I purchased the Esoteric, and it sounded much worse than my 15 year old Musical Fidelity player for the type of music that I listen to (purely acoustic classical); however, the dCS were much better for rock n' roll bass response.  

Nevertheless, please try to contribute to the subject matter of bit sampling effect on DAC/CD playback.  

Thanks. 

drbond OP
396 posts
 
@itsjustme 

What do you perceive as the greatest challenges and areas for digital to excel?

Thanks. 
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