I mean, what you can easily do with an FPGA is to use fixed-point numbers with whatever wordlength is required. So for a FIR, you can round the coefficients to some finite wordlength. That will result in frequency response errors (and only frequency response errors), but you can keep those as small as you like by using long enough coefficients. The multiplications and summation can then be done in full precision - if you need 71 bits for the sum, you use 71 bits, no need to round anything to some standard wordlength.
Dithering and rounding the result to the DAC wordlength will add some quantization noise, but that's inevitable.
Dithering and rounding the result to the DAC wordlength will add some quantization noise, but that's inevitable.
Hi jpk73, how's the performance of your FIR with AD1862 compared with others? I am using the same DAC and is looking for a good way to listen to hi res music.
Can you please explain a little bit about the sound differences and why you prefer NOS to the 16x FIR board?
It is smoother. You may put on yours to check as well
Yes, I will! Smoother is better??? I often consider smoothness as lack of texture. Some modern DACs sound so smooth that I find them unnatural. Instruments sound artificial, voice is without breath... (I am not talking about the 16x FIR board)