You have temperature dependence and long-term drift, but those are slow effects that can't spectrally spread out the ultrasonic content much.
There is mixing with noise, hum or interference on the DAC reference or clock. That can be a problem when the huge ultrasonic quantization noise of a sigma-delta DAC mixes with some clock harmonic or so on the reference voltage. I don't see how it would make the audio performance very sensitive to the interpolation filter type.
On the digital side, decimation is the only time-variant effect I can think of. When something needs to be decimated, you have to make sure that anything that could alias to the audio range is very well suppressed. This is not applicable to interpolation by an integer factor, though.
I must of missed the bit where you called me out about what I said sound is. Subjective listening impressions are useful to members who want to experiment, you know, diyaudio
Last time I've checked DIY is about building and/or fixing something tangible. Sharing subjective impressions do not qualify as such.
But I understand, we have absolutely no common ground, not even in definitions. Though, as much as your posse can call me a troll, I will call your subjective stories for what they are, too.
You forgot the audio bit, and audio is subjective, people like to experiment to see what sounds better to them. I don't know who my posse are and I didn't call you a troll.
To nitpick a bit, decimation does not necessarily lead to a time-variant system. The classical counter example is a discrete wavelet transform, followed by its inverse. Typically, this transform includes an aliasing cancellation (e.g. by using quadrature mirror filters), enabling the reconstruction of the original signal even when decimation was used in the discrete wavelet transform, making the system shift-invariant (time invariant).
However, the above example is not a practical use case, since between the discrete wavelet transform and its inverse some processing is included, which breaks the aliasing cancellation.
It would also theoretically work by using perfect anti aliasing filters, but of course these are also not practical (require infinite length).
Funny how this applies only to the human auditory sense, haven't heard of anything similar for the visual sense. That's because the auditory sense is the easiest to fool.
The auditory sense is certainly easy to fool. Other senses are subjective too though, many people seem to like the colour on their TVs set to what appear to me garish and unrealistic levels.
I will if you really want, but you can't tell me who my posse are because I don't have one, I'm expressing by personal subjective opinions, so, no deal.
Sorry, I'll get my coat, and follow the wise example set by members in this thread and ignore the irrational demands of zealous objectivism
So do I, and leave the troll calling high end audio developers to pursue their business. Hiding a business plan behind the DIY label is apparently the nom du jour.
And some are still wondering why I have no issues with those operating a small business here, without smoke screens, false/outrageous claims, name calling, insulting everybody's intelligence, etc...
And some are still wondering why I have no issues with those operating a small business here, without smoke screens, false/outrageous claims, name calling, insulting everybody's intelligence, etc...
Too many conspiracy theories.
How convenient, really? It appears to me the Andreas business model is expanding.
