Don't get me wrong. I love hearing others' impressions especially when they are totally different from mine. It's just that these misconceptions about NOS have been driving me nuts for over a decade now. It only took an expenditure of $30k for the APx555 to finally clarify these points! Don't defend NOS via science. Just love it for the sound! I mean, look at me. Vinyl totally sucks balls when it comes to science and measurements. Although I would point out that despite the errors, they are analog errors and not quantization errors at the ADC, but that's another story. As an aside please donate. See bottom right of the Home Page. I don't ask you guys for this every post like Amir. We need money for the sake of audio science. By the way, NOS DACs without analog reconstruction filters don't need a cap in the output stage - this could provide some benefits with respect to "immediacy". Also, impulse response with NOS DAC will likely not have the amount of ringing found from the use of linear or minimum phase filters used in oversampling DACs. Although this ringing is out-of-band, and in theory not audible, I have some doubts. People have been able to hear differences. (Heck, people here have been able to discern absolute polarity), something that I didn't think possible! There are lots of parameters that can be tuned with such filters: roll-off, transition-band width, passband cutoff, stopband demarcation, stopband attenuation. Changing these will have different effects, so it's hard to generalize. Foobar users can download the Resampler-V plug-in to play with some of these parameters for linear and minimum phase filters. No need for HQplayer, although HQPlayer does offer way more complex filter types.