DAC of the Year
There was a little category confusion around here this year — so many products doing more than one thing, and later on you’ll encounter another ‘DAC’ in our preamplifier category, because amongst other things it has inputs and a volume knob, so it’s clearly more than just a DAC. Nor should one describe the $2695 Prism Sound Callia as “just a DAC” — the UK digital specialist knows a thing or two about digital conversion, being an old hand in the professional audio sphere. Prism Sound’s first professional DACs and ADCs rapidly became popular in recording studios around the world, and its world-first AES/EBU interface analyser became the standard tool for broadcasters around the world, including the BBC, NHK, NBC, CBS, ABC and CCTV.
It is a relatively new name in home audio, but with products like the Callia, it should become known in this arena pretty fast as well. The Callia is physically quite small (285mm wide) and correspondingly light, at 2.1kg. As with our preamp winner it has a volume knob (and a lovely one, surrounded by a ring of blue LEDs that illuminate to give a visual representation of volume setting) in control of its line outputs, of which there are both unbalanced and balanced — so you could use it as a preamp, but a fairly limited one, given only three inputs, all digital: one USB-B for connection to a computer, plus one coaxial digital and one optical digital input. Input switching is managed automatically, with the Callia automatically detecting an active digital input and switching to it, after which it ‘locks’ into position and shows the format of the data stream on the front panel.
Internally, Prism Sound does most of its processing using in-house algorithms, via a Spartan-6 FPGA and 32-bit ARM Cortex microcontroller along with Prism Sound’s own clocking circuitry, which it calls a ‘CleverClox’. This is a hybrid phase-locked loop that locks the Callia’s clock to the selected SPDIF source with better than ±50ppm local clock accuracy, resulting in ultra-low jitter, claimed to deliver >60dB/decade above 100Hz jitter rejection. Although some Cirrus Logic CS4398 DACs are on the PCB, Prism Sound reportedly uses only their final switched-capacitor stage.
The results are thrilling to hear, with even the most complex music delivered with the ‘weave’ of the music intact while at the same time uniting the threads into a glorious tapestry of sound. It was always enjoyable, and frequently jaw-dropping in comparison to our previous references at the price... and an additional bonus in its awesome headphone output, which has its own dedicated volume control, and drove the toughest of our headphones with outstandingly transparent sound.
Given its potential minor role as a preamp, a remote control might have been a nice inclusion... but the Callia’s musical prowess sweeps away any such niggles. More info: www.prismsound.com
“A pro digital company turns to the audiophile market and delivers a doozie of a DAC in the Callia. Its conversion of digital sources is thrilling to hear.