This post delves into digital filters in AK4490 and AK4493 DACs used in W-DAC boards and provides extensive measurement results of the filters in time and frequency domain. This is not only relevant to these specific DAC chips and filters but general information on DAC digital filters from audio perspective. This is a practical approach – no poles, zeros, or formulas but lots of plots.
Progress has been slow due to other things in life but last few weeks have been busy on finalising everything. More measurements have been done and PCBs are finalised. First batch of boards is in production and should be available in September.
Follow-up on AK4490 test board measurements
- Comparing cheap LDOs to superb LT3042
- LP2992 shows excellent performance
- AK4493 vs. AK4490
- Even better performance
- Almost pin compatible
- New v1.1 boards in production
- Slightly larger but still ‘wee’
- Supports AK4490 and AK4493, and different LDOs
- Possibly two or three assembly versions with different price and performance