SACD vs. Blu-Ray for audio quality/sonics

AudiogoN members continue to be much of a light for knowledge.  Thanks, Jim

Some history from Philips research: https://www.philips.com/a-w/research/technologies/cd/technology.html

@rAndy-11 

Yes avoiding brickwall filters helps with passband ripple - this has been the long standing argument for upsampling. However randomization of DAC non-linearity is not well understood. Basically the higher frequency noise in high sample rates act like another form of dither that remove the quantization level errors of the DAC itself. 

Of course, the latest chips use other techniques too. The ESS chip in the Benchmark DAC 3 randomly selects which 1 bit sigma delta is used to convert (128 to choose from). This randomizes non-linearity. This is why I believe the latest devices sound like the best analog and why many like DSD or upsampling. or high sample rate files over redbook. The jitter monster was slayed about 15 years ago but only recently have designs addressed the inherent non-linearities of the levels in the DAC itself.

do you know how  ESS chip in the Oppo 205 is implemented?

@randy-11 

I think the Oppo has two of the 9038 chip - one used for multichannel and the other for stereo.  The noise reduction through random selection of sigma delta 1 bit from a multitude of 1 bit dacs is the standard logic used on this chip.