Short explanation/confirmation needed for digital filters

[Miska]

1 hour ago, yamamoto2002 said:

But (this is my understanding, it can be wrong) , minimum-phase filter cannot place zero on the unit circle of Z-plane therefore it cannot eliminate stopband signal completely, while linear-phase filter can place zero on the unit circle. Also I feel math is more difficult on designing minimum-phase filter

 

Both filters can have exactly same frequency response, only different phase response. That is the case with mine.

 

1 hour ago, yamamoto2002 said:

Apodizing means some reduction of ringing of time domain, this means very steep brickwall filter is not possible. I'm not sure it is the way to go for everyone or not. You may choose any digital filter you liked the most by listening music using your DAC-R. Personally think the sound difference of digital filters is very small

 

It means just replacing the original ringing with something else, shorter or longer. I have both... But more important effect is to reduce adverse effects of current ADC filters.

 

[Miska]

47 minutes ago, mansr said:

Apodizing filters are by definition slow roll-off.

 

Not necessarily, for example the ESS one is "sharp" roll-off...

 

I do both, relatively slow ones and also extremely steep ones.

 

In fact the first apodizing filters were pretty steep. While many of the newer ones, like MQA are very slow roll-off and in fact likely don't anymore even function as apodizing filters because of that. (if a filter doesn't really filter anything it cannot do much either)

 

[Miska]

10 minutes ago, mkrzych said:

Thanks @Miska! It seems very dependable on the implementation, so in case of Wolfson WM8742, what is that?

 

That is one of the "original" and similar to the ESS one, so goes into "steep" category. If you can select filter, the Filter 5 is quite nice.

 

P.S. It is also one of the chips that has nice DSD Direct mode. Being a bit old it is just limited to DSD64.