Note, I compare PCM and DSD on a DAC with real PCM and DSD conversion.
There is no point to compare with SDM DACs where PCM inputs result in DSP processing like oversampling and SDM conversion. Or likewise DSD inputs may involve conversion to low rate PCM (Chord).
Yes, DSD has much better attack and leading edge, with more weight. While PCM sounds flat, shallow and congested. This effect is smallest at 1.5M PCM, but still there. Like with DSD the drum sounds like a real “thump-thump” while on PCM it just sounds like “flap-flap”. With PCM, the body is missing.
So far, to me, ASDM7EC modulator gives the cleanest transients. I was kind of surprised how big difference it was over ASDM7, given how low in level the differences are. Listening to DSD256 recordings is also very nice. With DSD64 recordings the results clearly depend on the ADC used.
There are now at least two nice DSD256 ADC’s, Merging and RME.
Yes, insufficient reconstruction due to low digital filter oversampling rate. With PCM you can reach at most 1.5M. This still leaves images and thus incomplete reconstruction. Another reason are linearity errors. This is where listening experience and measurements correlate, when digital filter output rate is increased and linearity errors corrected with a noise-shaper and reduced bit-depth the adverse PCM effects are lessened.
When I run the DAC at DSD256 rate, I can run digital filters up to 256x instead of 32x (1.5M PCM) and the modulator ultimately solves linearity problems.