Round N°2: D300Ref⇔T+ clock-sync'd vs. D300Ref⇒Gaia⇔T1 clock-sync'd. Whilst very close, this match did slightly favor the more direct path for its even greater – um, directness. Of course very few people would ever make this comparison. Though very unjust, the use of SD cards for cutting-edge replay is just too obscure. Now that feature on the Soundaware becomes redundant and Gaia the more affordable of the two. Case closed? Not quite. This is the perfect juncture to impress upon prospective buyers that the Terminator-Plus clock-sync feature isn't necessarily all roses. With the wrong speaker, it could expose certain thorns. I mean that quite literal. Things could get a bit prickly.

What might the wrong speaker or amp/speaker combination be? Something that toes the line of hyper enunciation already. I'd point at a Cube/Voxativ-type widebander or Alain Pratali's quasi widebander of Aurai Audio M1. If you're sensitive and appreciative of musical flow and a certain relaxed and easy elegance, overdoing the aspect of ever more precise enunciation can eventually feel a bit unnatural. It can conjure slightly glassy undertones or a perspective that feels too close up and down-the-throat explicit. A few buttons defeat clock sync and we don't yet account for swapping clock cables to learn what voicing freedom they might offer. Regardless, think of clock sync as increased focus and transient acuity. It leads to crisper detailing. Its relative virtue will depend on your existing system balance. How do you prioritize between easy flow as though from a somewhat greater distance versus more specific precision from a seemingly lesser distance?

Clock sync acts as though your ears as microphones moved closer in on the music action. Your listening distance doesn't change. Still, your ears seem closer because focus locks down even tighter. What if your primary source is USB? How would Gaia behave as a USB-in/I²S-out bridge? That's how we use our D300Ref when not in SD card mode. That's how I'd use Gaia now.

Round N°3: iMac⇒T+ vs. iMac⇒Gaia⇒T+ vs iMac⇒Gaia⇔T+ clock-sync'd. This round split into two, headfi and speakerfi. For headphones, Kinki Studio's Vision THR-1 saw balanced signal from the Vinnie Rossi L2 DHT preamp and fed Final D8000 via a custom balanced leash from Campfire Audio's Ken Ball.

The Japanese planarmagnetic full-size headphones are very bassy and full-bodied. They're not voiced for maximum speed and impulsiveness like the Aurai Audio M1 2-way towers on the same floor. Final's sonic profile thus scattered to the wind all prickly precautions. Dust to dust. They adored the 2-stage resolution increase of first USB bridge then clock sync over running the iMac's USB through Audirvana 3 direct to DAC.

All that the words 'resolution enhancement' would promise factored except for gains in soundstage depth. Here headfi is hamstrung against loudspeakers 3 meters into a room with double-high ceilings. But attributes like superior sorting; more apparent grip or focus; crisper separation of little stuff behind big stuff to get quieter things out of the shadow of louder things… all of it was on virtual display.

Tone and timbre were comprehensively covered by direct-coupled Western Electric VT52 and an amp whose review had called it "strong on colors and earthy robustness which… isn't about close-up details but the stuff  behind  them: tonal weight, foundational power, color saturation and a milieu of organic warmth." 

It made for a truly ideal mix of Harbeth-type richness with e-stat detail. That finer detail came from the extra stage of reclocking and buffering inside Gaia. Once again clock sync via two Audio Art Cable Statement Digital—OCC silver, Oyaide BNC—added atop that finer detail a sense of greater rhythmic perspicacity. Think of nails on glass tapping out more precise beat code than fleshy finger tips would.