NAD M28 7-Digital 7 Channel Power Amplifier

EXTREMELY POWERFUL 7-CHANNEL POWER AMPLIFIER

Hybrid Digital Purifi self-clocking amplifier

Purifi is a Danish technology company where some of the leading developers in the hi-fi industry are pursuing the goal of identifying and eliminating the last remaining weaknesses in digital amplifier technology. The current status of their work resulted in the Purifi self-clocking amplifier, which NAD is the first company to produce under license and has so far been used exclusively in the BluOS streaming amplifier M33.

The Purifi self-clocking technology convinces metrologically with extremely low intermodulation distortion, a particularly low distortion factor over the entire frequency response and the entire power bandwidth - only 0.00017% at 100 watts of output power! – as well as a minimal self-noise. Since the distortion of the amplifier is lower than the inherent noise of the measuring devices used today, Purifi first had to develop new measuring methods in order to be able to prove and document the progress.

The realization that a memory effect occurs in the components in the output filter of the amplifier was groundbreaking for the development of the self-clocking technology. This phenomenon, called hysteresis, obviously leads to the well-known loss of sound of conventional digital amplifiers. By modifying the output stage and using the clever algorithms of the self-clocking technology, Purifi managed to reduce the hysteresis effects by more than 75 dB. Another advantage of the self-clocking power amplifiers is that they are absolutely insensitive to changing speaker loads. Their extremely low output impedance also leads to a very high damping factor, which is reflected in absolutely clean and controlled bass reproduction.

Balanced signal transmission

In recording studios and in professional sound reinforcement technology, symmetrical signal transmission has been part of good sound in the truest sense of the word for many years. It transmits the audio signals not via a single but via two conductors, which means that possible interference is excluded, even over longer cable runs. In addition to gold-plated cinch sockets, the M28 also has balanced XLR inputs, which ensure interference-free signal feeding without noise or interference.

MAIN FEATURES

HybridDigital Purifi self-clocking amplifier
Continuous output power (2 channels driven): 220 W into 8, 400 W into 4 ohms
Continuous power output (all channels driven): 200 watts into 8, 340 watts into 4 ohms
Pulse Power: 280 watts into 8 ohms (all channels driven), 560 watts into 4 ohms (one channel driven)
balanced XLR inputs
gold-plated RCA inputs
12V trigger input
automatic switch-on
ground terminal
Separate power cord