SR1a revisited

Reviewer: Srajan Ebaen
Financial interests: click here
Sources: Soundaware A280 SD card transport
D/A converter: Jay's Audio DAC-2 Signature Edition
Preamplifier: Nagra Classic
Amplifiers: Nord Acoustics NC500 monos with Rev D buffers
Review component retail: $3'499

Living with the SR1a since their review meant that I'd pretty much thrown everything at them that's come through since. The above is their current golden ticket or silver bullet. After having properly broken in the new Rev D buffers in the Nord Ncore 500 monos plus having a Jay's Audio DAC-2 Signature Edition on hand… the one thing I was still shy on just then was a proper preamp. On a lark, I brought upstairs our Nagra Classic. It wasn't hooked up downstairs where a Wyred4Sound STP-se II did battle against a Pass Labs XP-12. A snoozing Nagra is a major waste.

Without any particular foresight then—but plenty of self-congratulatory hindsight if I'm honest—this particular combo combines wide bandwidth low-impedance tubes with class D. It's a recipe that's worked out astonishingly well. Raal's amplifier interface box basically presents as one enormous load resistor. Consequently, Ncore's much ballyhooed steep damping factor from ultra-low output impedance gets completely annulled. It's like a bad marriage that never was. That happily eliminates what on our resident speakers remains my main critique of these class D amps. They overdamp the musical flow. Our class A Pass Labs XA.30.8 beats them up badly on bass swagger and general juiciness. Our 1MHz class A/B LinnenberG Liszt throw in more sophisticated treble.

But, driving Raal Requisite's black box erases all of that. Now these amps just provide high current with extremely low noise and do so demonstrably translucent to the preceding small-signal triodes. Those magnify the expanded tone modulation skills of the Chinese Asahi-Kasei based converter. Granted, here the Nagra is the odd man out with its 5-figure tab. But I'd be surprised if a $699 Schiit Freya wouldn't do a good job instead.

The moral of this 'Revisited' feature is simple. Affordable class D preceded by tubes can make for a perfect SR1a setup and a cool-running compact package that suits this headfi purpose well. With our LinnenberG and Pass amps needed in the main speaker system, I couldn't permanently allocate them to the Raal Requisite rig. Preferring them on our speakers over the Nord, I now had two Ncore monos for spares which were looking for gainful employment. It's when I chanced upon the notion of roping in the swish Swiss Nagra that things really clicked. In conclusion, those who contemplate ownership of the Raal Requisite ribbon earfield monitors but who wonder what likely expensive speaker amp to get might duplicate my tubes+class D recipe according to their own budget and taste. And that might just equal my own happiness. In which case, this anecdotal evidence would have served a purpose…