Although Purifi is a new company (established 2017) its founders, Bruno Putzeys (Philips, Hypex, Kii Audio), Lars Risbo (Toccata Technology, Texas Instruments), and Peter Lyngdorf (Hi-Fi Klubben, TacT, Dali, NAD, Snell, AudioNord, Steinway-Lyngdorf) are all household names in the audio industry.
Purifi’s first product, the 1ET400A, 400-watt Class-D amplifier module (pictured above, click on image to enlarge), was shown for the first time at the recently-concluded Munich High End, 2019. The technology is said to be completely indifferent to frequency, level and impedance variations, with lower levels of THD and IMD than any other amplifier available. The company claims ‘extraordinary low noise’ (~11.5μV A-weighted), THD+N of less than 0.00017%, output current of 25 amps, and dynamic range of 131dB. It also claims 94% efficiency for the module when it’s delivering 400-watts into 4Ω.
Putzeys, who holds patents for Hypex’s much-vaunted NCore and UcD technologies, created a new Class-D technology for Purifi known as Eigentakt (‘self-clocking’), which he says was the result of his research into the self-oscillation behaviours in Class-D amplifiers. Putzeys claims that the circuit, using new algorithms in control loops, improves on all existing Class-D designs by an order of magnitude or more and it’s this technology that NAD will adapt to suit its signature design requirements.
‘The Eigentakt technology is unique,’ said Putzeys. ‘Amplifiers using the technology will be indifferent to speaker load, volume level, and signal content, resulting in negligible THD and IMD levels, and will feature exceptionally clean clipping while at the same time delivering a frequency response in the audio band that is within ±0.01dB under all load conditions.’
Gordon Simmonds, CEO of the Canada-based Lenbrook Group, which owns NAD Electronics, Bluesound and PSB Loudspeakers, told Australian Hi-Fi Magazine that the design team at NAD, led by Greg Stidsen and Taresh Vadgama, had been working with Putzeys, Risbo and Lyngdorf for many years. ‘Clearly, we all share the same commitment to audio excellence so NAD is pleased and proud to be at the forefront of adopting Purifi’s class-leading technology,’ he said. ‘Our teams are already fully engaged in the process of developing a next-generation amplifier platform that will feature this circuitry, keeping NAD and our other brands at the forefront of audio technology as it begins to weave into our product roadmap.’
‘I have personally been involved with NAD Electronics and have known the Lenbrook team for 40 years,’ said Lyngdorf. ‘NAD is the perfect collaboration partner for this new technology and we look forward to their implementation, as we are sure it will propel the industry’s expectations for high-fidelity amplifiers.’
For more information, contact NAD’s Australian distributor, Convoy International