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Setting expectations? Time-domain performance in speakers tends to be all over the place. Opinions about the audibility of time coherence vary just as broadly à la 1st-order argument. Would it be reasonable to think that listeners insensitive to measurably more time-correct speakers could be just as inured to the echo-less charms of NOS DACs? Proponents of standard digital filters must believe that pre/post ringing is inaudible and merely a theoretical blemish. NOS DAC adherents must believe that it's quite obvious. Does hearing it require familiarity to perceive; or perhaps suitable ancillaries to become more pronounced? The Martin Colloms review provides a useful tidbit. "... It results in a very
truthful and articulate sound particularly
evident on piano [emphasis mine - Ed.].
Piano strings are struck by falling hammers to produce a mix of metallic transient when the string is first excited followed by the resonant response of the amplifying soundboard and physical wooden carcass of the instrument.
More exaggerated on the leading edge are the spinet, virginal and harpsichord. Their strings are mechanically plucked in a sort of permanent needling pizzicato, their sound bodies more compact to add less redolence. This allows a keen focus on transient behavior over a far broader multitude of tones and harmonics than the usual percussion.
Power filtering block at right.
If part of the NOS DAC appeal is superior impulse fidelity—apodizing filters attempt to duplicate this—a few harpsichord or perhaps qanoun/cymbalom sessions should be helpful to corroborate its extent. Needless to say, natural transients don't imply hyped sharpness (etchiness in common hifi parlance) but cleaner more articulate enunciation. That said, higher percussive precision doesn't make for an intuitive tie-in with that greater organic flow one keeps reading about as perhaps the loudest claim for zero-sampling zero-filtering D/A conversion.
Surprisingly sizeable output transformers.
How would those two seemingly mutually exclusive qualities manifest in the 1543 DAC? For context one corner would have 20 x AK4399 32-bit chips per channel at 195kHz upsampling—that's no typo!—with a Lundahl-coupled E182CC output stage. The other corner would see 16 x undisclosed industrial chips without oversampling or digital filtering but Lundahl 1588 output transformers compliments of Metrum Acoustics' Hex.
White CAD with green backlighting and Concert Fidelity CF-080 LSX preamp with Psvane tubes.
For CAD's pending Revelation USB cable Scott has applied for a patent whilst production is to be subcontracted as he doesn't see himself manufacturing wire. When asked what distinguishes his USB cable—geometry, conductor, dielectric, shielding?—he chuckled and quipped that I'd not mentioned the most important ingredient. Though still tweaking certain details, he was quite certain that final production will feature a switched 5V power line. Users of component-powered USB transceivers will switch it off to disconnect computer power altogether; owners of USB-powered solutions will leave it in the circuit: one cable to support both scenarios.
