Topping Centaurus R2R DAC Review

[rocksteady]

Starting from 0 dB, to what specific fixed value would the digital volume—for example, on the D200—need to be lowered to ensure full resistance to ISO?

I thought the D200's volume control is Analogue? Or did I misunderstand?

 

[Roland68]

I thought the D200's volume control is Analogue? Or did I misunderstand?

That's absolutely correct, but that doesn't mean you couldn't add a preset in the firmware with, for example, -3dB on the digital side.
Of course, this also applies to other DACs with analog volume control.

 

[mocenigo]

Dacs can sound different, that isn’t news.
Keith

Of course. But that means one of three things:

- The analog interface between DAC and preamp or directly from DAC to power amp has an impedance mismatch.

- At least one of two directly compared DACs alters the sound, either intentionally (like certain tube output stages, but not only) or by broken/incompetent design.

- There is some other effect that we do not measure yet. One such example are the hysteresis effects documented by Purifi for amplifiers, but the likelihood of this is extremely, extremely low. Note that, like all audio artifacts, if something similar occurs, we can measure it but we need to understand first how to trigger it and what to measure. (I have always said that we should measure the behaviour with asymmetric signals, with the amount of asymmetry changing over time, as well as sums of components with different amplitudes. If there are surprises, we have gained knowledge. If there are none, we have gained knowledge as well.)

Roberto

 

[mocenigo]

The Denafrips Gaia DDC is using this «ARM Cortex-M4 core to achieve leading performance of 225 DMIPS and 608 CoreMark® at 180MHz executing from embedded Flash» for its FPGA DSP (EDIT: False. It was for USB audio). It looks more like a CPU for a mini computer/android device: https://www.st.com/en/microcontrollers-microprocessors/stm32f446.html

Could this be doing the DSP effects that Golden Sound is «hallucinating» about?

For a moment, I feared this would lead to a discussion over audiophile CPUs…

 

[mocenigo]

I would take ‘golden sound’ with a large pinch of salt.
Keith

I would say that is pyrite, not gold.

 

[mocenigo]

That's absolutely correct, but that doesn't mean you couldn't add a preset in the firmware with, for example, -3dB on the digital side.
Of course, this also applies to other DACs with analog volume control.

I reduce the signals by 3dB at the source with moOde on my Pi, then apply up sampling and reconstruction to 352/384, all at 32 bits of resolution, before sending the resulting stream to my D90 (very first series).