@teo_audio
Just because there are many bad sounding (screeching as you put it) Delta Sigma DACs does not mean that none of them are any good.
The latest Delta-sigmas use multiple 1 bit converters to achieve the same as a 6 bit R2R DAC. You can understand how a ladder DAC takes output from a resistor network where a small number of resistors are exact multiples of each other (1x,2x, 4x, 8x etc). Well you can also build a network from the SAME 1x resistor but simply by using a huge number of them. This is in effect what new Sabre Delta Sigma DACs do - 64 x 1 bit DACs - and by summing them to various degrees you get up to 6 bits.
So the line between R2R and Delta Sigma is blurred when you realize that the latest Delta Sigma chips are behaving much like an R2R DAC (but only a 6 bit one). The end result is that the latest Delta Sigma DACs are extremely linear (benefit of 1 bit) and yet they also do not need to upsample nearly as much as older generation pure 1 bit DACs (without a 64 array).
Of course an R2R DAC can be designed to be NOS however this is at the expense of linearity (THD) performance.
Since multibit DACs have great low noise but poor linearity and the 1 bit DACs have excellent linearity but high noise NEITHER are purely the best approach - the 6 bit DAC with some oversampling is currently achieving the best performance.
More explanation here of how one designer has approached the challenge of noise and linearity.
https://benchmarkmedia.com/blogs/application_notes/inside-the-dac2-part-2-digital-processing
Furthermore, as this manufacturer states 90% of the circuitry and the major part of DAC performance is all in the ANALOG design (so according to manufacturer much of the performance is NOT even related to Multibit R2R NOS vs Delta-Sigma digital conversions)
https://benchmarkmedia.com/blogs/application_notes/149341191-inside-the-dac2-part-1-analog-processin...
Conclusion (if you buy this line of reasoning): It is far far more important how well the DAC is designed and built than the specific digital conversion chip employed (1704, 9018 etc)!!!!!!!
Excellent sounding DACs do not ALL have to use the same exact methodology and there is more than one way to skin a cat.
Just because there are many bad sounding (screeching as you put it) Delta Sigma DACs does not mean that none of them are any good.
The latest Delta-sigmas use multiple 1 bit converters to achieve the same as a 6 bit R2R DAC. You can understand how a ladder DAC takes output from a resistor network where a small number of resistors are exact multiples of each other (1x,2x, 4x, 8x etc). Well you can also build a network from the SAME 1x resistor but simply by using a huge number of them. This is in effect what new Sabre Delta Sigma DACs do - 64 x 1 bit DACs - and by summing them to various degrees you get up to 6 bits.
So the line between R2R and Delta Sigma is blurred when you realize that the latest Delta Sigma chips are behaving much like an R2R DAC (but only a 6 bit one). The end result is that the latest Delta Sigma DACs are extremely linear (benefit of 1 bit) and yet they also do not need to upsample nearly as much as older generation pure 1 bit DACs (without a 64 array).
Of course an R2R DAC can be designed to be NOS however this is at the expense of linearity (THD) performance.
Since multibit DACs have great low noise but poor linearity and the 1 bit DACs have excellent linearity but high noise NEITHER are purely the best approach - the 6 bit DAC with some oversampling is currently achieving the best performance.
More explanation here of how one designer has approached the challenge of noise and linearity.
https://benchmarkmedia.com/blogs/application_notes/inside-the-dac2-part-2-digital-processing
Furthermore, as this manufacturer states 90% of the circuitry and the major part of DAC performance is all in the ANALOG design (so according to manufacturer much of the performance is NOT even related to Multibit R2R NOS vs Delta-Sigma digital conversions)
https://benchmarkmedia.com/blogs/application_notes/149341191-inside-the-dac2-part-1-analog-processin...
Conclusion (if you buy this line of reasoning): It is far far more important how well the DAC is designed and built than the specific digital conversion chip employed (1704, 9018 etc)!!!!!!!
Excellent sounding DACs do not ALL have to use the same exact methodology and there is more than one way to skin a cat.