What's the typical line-level input voltage for an audio signal? Something like two volts? Four, peak-to-peak? A 16-bit ADC quantizes that four volts into 65,536 distinct quantities which are reproduced as voltage levels and hence, sound by a DAC on playback. Okay, fine, whatever. BUT... in a 100% analog process, the line-level input max is much greater than two volts. I've heard of analog equipment being able to register signals in excess of 70 V. This gives the audio engineer practically infinite headroom in which to record and mix sound without losing detail.

Where analog generally falls down on the job is, you typically need actual musicians playing actual instruments in an actual studio to lay down a track. None of this wave-table-synth, virtual instrument shit. And no Auto-Tune or other automatic correction either; if a musician flubs a track, generally they have to rerecord it. Pop producers consider this a bug; serious musicians consider it a feature.

And a 24 bit ADC that quantizes the lower 16 bits into 4Vpp would be capable of registering signals at 512Vpp. No analog devices have such a large headroom (granted they don't build such a device, but if you attenuate the signal at the entrance to the ADC, you get something similar).

This, btw. is why nobody masters at 16 bits; the insufficient headroom. 16 bits is plenty for playback though.

[edit]

I do want to acknowledge the big weakness of a digital setup that you touch on here, which is the hard clipping. If you ever clip in digital, you have ruined the recording while many analog setups will have a soft rolloff (Tube amps v. BJT amps are similar; the soft clipping of a tube amp is much less unpleasant than the hard clipping of a BJT amp. You can "get away" with a lower wattage tube amp for this reason; a properly sized BJT amp is more accurate though). All this is moot for professional recordings though as a sound engineer who regularly clips by accident (rather than to intentionally get a particular sound) will get fired.

> No analog devices have such a large headroom

Obviously you've never mastered a Disaster Area album. :)

Voltage isn't particularly relevant of itself; what's that in dB above the noise floor?