what is the difference multi bit delta sigma and multi bit ladder resistor network pcm1704

[derekchan]

can anyone tell the difference
cd6007 ak4490
eversolo a8 4491+4499ex switch reistor
exposure 3510 cd player pcm1704 r2r

speaker jbl 4309

 

[MaxwellsEq]

can anyone tell the difference
cd6007 ak4490
eversolo a8 4491+4499ex switch reistor
exposure 3510 cd player pcm1704 r2r

speaker jbl 4309

When well implemented with excellent reconstruction filters, a R2R and a DeltaSigma DAC should both perform better than human hearing.

R2R DACs are trickier and more expensive to get right. They are also more likely to drift away from correct settings over a prolonged period or where temperature and humidity vary considerably.

So, there is no real need to have an R2R DAC, and a few reasons why (cost, precision, drift) you might choose not to have one.

 

[derekchan]

When well implemented with excellent reconstruction filters, a R2R and a DeltaSigma DAC should both perform better than human hearing.

R2R DACs are trickier and more expensive to get right. They are also more likely to drift away from correct settings over a prolonged period or where temperature and humidity vary considerably.

So, there is no real need to have an R2R DAC, and a few reasons why (cost, precision, drift) you might choose not to have one.

do you need upsample 44khz and oversample 16x
is it necessary
does it modify the bit data of 16bit 44

 

[MaxwellsEq]

do you need upsample 44khz and oversample 16x
is it necessary
does it modify the bit data of 16bit 44

I don't understand your question.

 

[derekchan]

I don't understand your question.

i can see the pcm1704 manual said this r2r dac has 8x oversampling
and a naim nd555 dac built in pcm1704 feature upsample 44khz audio to higher sample rate plus 16x oversampling
are these extra upsample and oversample necessary to d/a conversion pcm audio?
back in 80s 90s those pcm1704 dac cd player no use to oversample right?

 

[MaxwellsEq]

i can see the pcm1704 manual said this r2r dac has 8x oversampling
and a naim nd555 dac built in pcm1704 feature upsample 44khz audio to higher sample rate plus 16x oversampling
are these extra upsample and oversample necessary to d/a conversion pcm audio?
back in 80s 90s those pcm1704 dac cd player no use to oversample right?

Much has changed.

Making truly linear R2R DACs is extremely difficult and they are sensitive to temperature and drift over time.

Making pure analog reconstruction filters with low ripple, good phase behaviour, flat frequency response and excellent stop-band attenuation is pretty much impossible.

Oversampling and filtering in the digital domain has resulted in DACs with better reconstruction filters that are also more linear. They are less sensitive to temperature and more stable over time.

 

[melomane13]

Oversampling in audio DACs dates back to the very beginning of the CD, in the early 1980s.


Historical milestones:

• Philips introduced digital oversampling (4x, with a digital filter) as early as 1982-1983 on its first CD players (such as the CD100), paired with the 14-bit TDA1540 DAC. The idea: oversample digitally to push the analog anti-aliasing filter's cutoff far up in the spectrum, easing the constraints on the analog output filter (which, without oversampling, has to be a steep "brickwall" filter right at 20 kHz — hard to achieve without degrading phase response and sound quality).
• Sony, at the same time, instead used "non-oversampling" DACs (NOS, 1x) with more conventional analog filtering on its early players.
• Oversampling then became widespread and progressively more aggressive: 4x, 8x, and eventually modern delta-sigma DACs oversample massively (sometimes 64x, 128x or more) combined with noise-shaping — this became the dominant standard from the late 1980s / early 1990s onward, with the rise of delta-sigma (Philips' "Bitstream," then adopted by nearly every manufacturer).

So to sum up: the principle has existed for over 40 years, and the "NOS" (non-oversampling) movement seen today among some high-end R2R manufacturers is actually a deliberate return to the pre-oversampling approach of the very first CD players, driven by sonic preference rather than pure technical performance. Marketing only ...

 

[derekchan]

Oversampling in audio DACs dates back to the very beginning of the CD, in the early 1980s.


Historical milestones:

• Philips introduced digital oversampling (4x, with a digital filter) as early as 1982-1983 on its first CD players (such as the CD100), paired with the 14-bit TDA1540 DAC. The idea: oversample digitally to push the analog anti-aliasing filter's cutoff far up in the spectrum, easing the constraints on the analog output filter (which, without oversampling, has to be a steep "brickwall" filter right at 20 kHz — hard to achieve without degrading phase response and sound quality).
• Sony, at the same time, instead used "non-oversampling" DACs (NOS, 1x) with more conventional analog filtering on its early players.
• Oversampling then became widespread and progressively more aggressive: 4x, 8x, and eventually modern delta-sigma DACs oversample massively (sometimes 64x, 128x or more) combined with noise-shaping — this became the dominant standard from the late 1980s / early 1990s onward, with the rise of delta-sigma (Philips' "Bitstream," then adopted by nearly every manufacturer).

So to sum up: the principle has existed for over 40 years, and the "NOS" (non-oversampling) movement seen today among some high-end R2R manufacturers is actually a deliberate return to the pre-oversampling approach of the very first CD players, driven by sonic preference rather than pure technical performance. Marketing only ...

how about upscaling 44khz to much higher hz on naim nd555 on 40bit sharc dsp chip？
does it cause bit UN perfect with bit data modified?

ok
if i am going to try nos 1x pcm1704 true r2r dac sound
which vintage pure cd player the best on today?
i can't afford exposure 3510 cd player pcm1704 are these still operate in 4x or 8x oversampling?

 

[Kremmen]

When well implemented with excellent reconstruction filters, a R2R and a DeltaSigma DAC should both perform better than human hearing.

R2R DACs are trickier and more expensive to get right. They are also more likely to drift away from correct settings over a prolonged period or where temperature and humidity vary considerably.

So, there is no real need to have an R2R DAC, and a few reasons why (cost, precision, drift) you might choose not to have one.

I know that there is a custom R2R DAC chip and resistor array in the Bluetooth adaptor that fits to my Hifiman Deva Pro Bluetooth headphones. It draws about 20 milliwatts when in use. I'm not an expert but I just thought I'd mention it here as I was prompted to do a bit of research after reading this thread.

HIFIMAN Debuts New Himalaya R2R DAC and Bluemini Hi-Res Bluetooth Adapter for Deva Pro Headphones

HIFIMAN is an innovative audio company that continues to offer improved designs for headphone enthusiasts. Already experienced with true wireless Bluetooth design, the company now focused on high quality wireless headphones and designed the Himalaya R2R DAC, a new low-power DAC module that fits...

audioxpress.com

 

[melomane13]

how about upscaling 44khz to much higher hz on naim nd555 on 40bit sharc dsp chip？
does it cause bit UN perfect with bit data modified?

ok
if i am going to try nos 1x pcm1704 true r2r dac sound
which vintage pure cd player the best on today?
i can't afford exposure 3510 cd player pcm1704 are these still operate in 4x or 8x oversampling?

Here, the consensus (and I agree) is that there's no difference in the sound of DACs, past a certain quality level that ensures transparency.

That level is surprisingly low, by the way, because our ears are poor tools... so what you're imagining doing is futile.

Put your time and money into what actually matters: the speakers, their placement, and room correction.

DACs (and amplifiers) have been a solved problem for 40 years.

 

[derekchan]

Here, the consensus (and I agree) is that there's no difference in the sound of DACs, past a certain quality level that ensures transparency.

That level is surprisingly low, by the way, because our ears are poor tools... so what you're imagining doing is futile.

Put your time and money into what actually matters: the speakers, their placement, and room correction.

DACs (and amplifiers) have been a solved problem for 40 years.

how about cheap av integ amp has high 10% thd,with non full bandwidth 20hz-20khz
also the cheap volume control of pre amp section will cut bit to make sound detail lost

 

[melomane13]

how about cheap av integ amp has high 10% thd,with non full bandwidth 20hz-20khz
also the cheap volume control of pre amp section will cut bit to make sound detail lost

Either you're a troll, or you have a serious comprehension problem, given how you jump from one thing to another.

 

[solderdude]

the cheap volume control of pre amp section will cut bit to make sound detail lost

No it won't.

does it cause bit UN perfect with bit data modified?

Whatever is done after a 'bit perfect' signal reaches any DAC remains to be seen and will as good as always be processed (upsampled for instance).
Use (digital) volume control, some resampling in an operating system or some DSP to a bit-perfect recording also changes the signal.
Sometimes even for the better...
Who cares about 'bit perfect' and what do you consider 'bit perfect' ?

if i am going to try nos 1x pcm1704 true r2r dac sound
which vintage pure cd player the best on today?

What do you expect from this ?

do you need upsample 44khz and oversample 16x

The 1704 DAC does not accept sampling rates over 96kHz so any upsampling of 44.1kHz should be 2x at most (88.2kHz)
And even then the filter used in the upsampler is also important so which upsampler do you want to use ?
Why use 25 year old DAC chip designs ?

Internal upsampling in the chip is 8x for 96kHz input signals.
For 44.1 and 48kHz signals the upsampling is 16x (assuming the right clock frequency is used).

In any case this is 'better' than NOS (Non-OverSampling) R2R DACs which are all the rage and can actually sound different (by lack of proper filtering).