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Fixed Multiplier Upsampling - Printable Version

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Fixed Multiplier Upsampling - Roen - 11-19-2016

It would be nice to either:

A: Set UAPP to do maximum upsampling of files for a given DAC maximum sampling rate constrained to the resulting sample rate being an integer multiple of the original sampling rate

For example, my DAC can do 32/384 and I'm playing a 16/44.1 song. I would rather UAPP upsample this file to 352.8, rather than 384, as it currently does.


B: Being able to pick a maximum integer scaling factor such that UAPP will scale files up to but not beyond a user set integer scaling factor for upsampling.

For example, my DAC can do 32/384 and I'm playing a 16/44.1 song. I would like an option to pick either 2 or 4 and end up with 88.2 or 176.4 for my upsampled playback.

Currently, UAPP will only go to the maximum, which in my case, is 384.

RE: Fixed Multiplier Upsampling - ReggiNason - 03-28-2019

Hi.......the main point of upsampling is to make the digital filter (part of the DAC) easier to design. When you upsample, you can inject zeroes or random data into the data stream, it doesn't change the end result. Strange but true; you'll need to read a book on signal processing to understand why things work that way. Anti-aliasing is different... if you filled in every second pixel automatically with black, an antialiased image would look terrible. Whatever efforts the programmer put in, I still believe the hardware design should also be improved by the manufacturers. I can't see the good pcb assembly and good quality components. These factors add the external noise and cannot be mitigated in firmware design.