01-01-2021, 09:26 PM
(01-01-2021, 08:51 PM)XORadmin Wrote: I don't really think it is necessary to have any extra adjustment points as again the response of the DAC is linear by specifications. If it is not the case with you then you got most likely a hardware problem and should contact me directly. Any additional adjustment points would be a workaround only I think (thinking twice about it)
I think this is disingenuous on your part. No hardware is perfect, there is a margin of error in all hardware that needs to be accounted for somehow, i.e. software calibration. It is not a workaround if you don't verify the response of every DAC that goes into your product.
The NerdSeq is already hindered by the use of a 12bit DAC for pitch duties in my opinion. 12bit alone is barely adequate for standard chromatic tuning, much less more exotic ones. Being 12bit and only using 2 calibration points is only asking for problems.
I have a Mutable Yarns which has performed flawlessly for me, it is a very precise piece of hardware. From the spec sheet for Yarns:
High-end 16-bit DAC and voltage references.
12-point calibration table, adjusted in factory.
I trust Émilie when she uses the term High-end. Not only is the DAC 16bit and "High-end", she still uses a 12 point calibration table. I wouldn't call it a workaround, I would say it is the right way to do it.
Another Mutable example is Marbles:
14-bit DAC with accurate software calibration - error below 1mV.
I don't have one to verify but I imagine similar calibration tricks are used in this module in order to make this claim.
Have you ever verified the linearity of the DACs you use?