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DACs and reproduced sound

I am trying to understand how to think of DACs effecting reproduced music (I am new to the hobby). I think of a DACs "role" as taking a digital input (1s and 0s) and a cleanly as possible processing that digital signal to an analogue output - goal is not impart anything on the processed data. The difference between a good and bad DAC seems like it should be on how well it does that. Or, said another way, from a review of a Benchmark DAC:

"The old regulars know exactly my position regarding the stupidity of ascribing a “character” to the sound of an utterly neutral signal path. Oohing and aahing over the vast improvement in soundstaging, front-to-back depth, bass delineation, or treble sweetness obtainable with this or that electronic component may sell high-end magazines but is totally unscientific and delusional. What the Benchmark DAC1 HDR adds to or subtracts from its input signal is borderline unmeasurable, so the sonic character of its output is obviously the sonic character of its input. It’s as simple as that. It has no sound of its own."

I sort of think of amplifiers and speakers (I am digital only listener)as being more important in "imparting" a particular musical flavor (warm, bright, etc.).

I am a bit new to the hobby so I would like any insights or be educated on DACs some more.
dangelod
mapman's avatar
mapman
22,610 posts
 
Dangelod,

I believe that is true in the case of the Benchmark, but is not always the case in that not all DACs reclock data.

Assuming a low end player relative to the BEnchmark, or also perhaps even just a poor connection from the digital source to DAC, the BEnchmark reclocking should result in lower jitter (errors in the timing) and better accuracy and detail.
kijanki's avatar
kijanki
4,445 posts
 
Dangelod - jitter is just only one of the elements and it is much more complicated than that. Benchmark asynchronously upsamples incoming digital data about million times to filter it in digital filter and output to 24-bit DAC at 100kHz rate. Filtering itself affects the sound and some prefer no oversampling and filtering at all (NOS DACs). Recently reviewed in Stereophile magazine Meridian CDP uses different filtering scheme and sounds much better (but costs $16k). DAC IC itself comes in different varietes to overcome resolution limitations. Benchmark is using Analog Devices Sigma-Delta DAC (similar scheme to SACD) that has 24 bit resolution (not obtainable in traditional DACs) but timing errors limit resolution anyway. Others use traditional DACs - some with statistical averaging (like DCS RingDACs) to improve resolution. Harmonic distortion play also important part. Benchmark updates DAC ,capable of 192kHz,at only 100kHz because harmonic distortions are much lower at this point. Important to remember is that there is no perfect DAC and everything is a compromise (and very complicated). Listening test will give you much more than reading spects.
marakanetz's avatar
marakanetz
5,473 posts
 
I agree that high-end magazines are delusional and unscientific. Nowdays it's very commercial rather than acheiving something scientific.
DAC despite processing 1's or 0's is a complexed logical device (especially today's advanced ones).
Our todays' CD digital format has 16-bit on 'vertical Y axis' and 44.1kHz samplig freequency on 'horizontal X axis'.
Giving example of the highest range of audiable freequencies such as 20kHz will roughly have only 2...3 digital samples * 16bit will yield 36bits of overall resolution.

First DACs processed one bit at a time. The advantage of these DACs is simplicity of the design and logic. The disadvantage is high probability of error meaning to give instead of 5-bits amplitude 3 or 7 bits amplitude since the 'receiving one-bit register' only cares about signal presence or absence i.e. '0' or '1'. Hence the quality of a digital equipment was 90% depended on the analog process which is filtering and buffering garbage.

Nowdays DACs are much more advanced they process sample by sample which may contain upto 24 bits amplitude and upto 192kHz sampling freequency. The proccessing by 'word' or taking the whole sample onto the register allows to logically analyze 'condition' of a particular word hence reducing drastically the probability of error. The DAC ICs are just like jewelry can be dirt cheap and can be pricey depending on what capability they all have and certainly newer and advanced models (such as Benchmark's relocking) would run at the higher price tag but soon will be reduced as the time passes by just like with PCs.

The listening difference vs. old processors is substantial especially on higher freequency details and also dynamics. Less listening fatigue and more natural sound.

The corresponding price of a digital equipment is another point of convincing price paid vs. performance, but often it's not true and not scientifically proven where I agree with poster since the fully functional digital unit that supposingly has the best DAC IC(s) and all possible functions, read all possible high resolution formats can't be priced $10k. Hence I don't think that there's something possibly more advanced and perfect than Grace Design M902 DAC-Preamp-Headphone amp.
mb9061
137 posts
 
anyone that says dacs don't sound different are full of crap. Anyone who says the benchmark gear is neutral or adds no "color" to the reproduced sound is even more full of crap. The thing upsamples, that in and of itself changes the sound, particularly of 44.1 redbook data. And it's a bright sounding dac. though a very clean sounding dac with tons of detail.
shadorne's avatar
shadorne
7,477 posts
 
The comment was surely about the analog preamp. A good preamp should indeed reproduce the input signal as closely as possible and good preamps should sound nearly identical, as they reproduce what they are fed. It s very hard to hear the difference between one excellent neutral preamp and another. No surprises there.

DAC's do sound different as they process the signal although differences are also very small but many people can hear these slight differences when listening critically and switching back and forth on the same track.
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