Ideally there is no influence on the sound with good filters. Apodizing filters roll the top off a little (perhaps not loosing as much as is gained by cleaning up other sloppier filters earlier in the processing path.)
Ringing the way most people think of it isn’t an artifact of a good filter. The fact of the matter is that signals that people often use to show “ringing” in a filter are not bandlimited: they are illegal PCM signals that don’t represent any properly bandlimited signal. “Curiously enough” a bandlimited impulse or step function has the ringing that many complain about - but we don’t perceive that ringing as an artifact at all. Poorly implemented filters can add ringing that isn’t in the original signal, in FIR filters the shorter the filter the more ringing (they are less like an ideal filter) With IIR filters the ringing can be limited to “post ringing”, but you can’t implement a stable digital IIR filter that does adequate antialiasing for full bandwidth PCM upsampling (just like you can’t implement an analog filter with a sharp enough cutoff to facilitate PCM upsampling, at least not of full bandwidth material.)
There is no DSD 8x upsampling filter in the DS - everything goes to 30 bits at 20 x the nominal DSD rate (DSD64) and then back to DSD256.
Note that almost all PCM dacs (or DSD dacs) aren’t really PCM dacs (or DSD dacs) as you are thinking of them: they almost all upsample PCM to a higher rate and then convert that PCM (or the incoming DSD) to fewer PCM bits (5, 6, 7) with a sigma delta modulator and then are sent those higher sample rate (but lower resolution) data to lower resolution DACs. A hybrid somewhere between the obvious non-oversampling PCM DAC and the obvious DSD based DAC.