NAD M28

Hybrid Digital Amplification

The Masters M28 uses Eigentakt amplification technology, manufactured by NAD under license from Purifi. This new technology, which NAD was the first to adopt for the Masters Series M33 streaming amplifier, adds another level of precision by accounting for the previously unknown effects of the output filter in the feedback loop and further refining the self-oscillating class D technology as used by previous NAD Hybrid Digital designs. The result is a level of performance that approaches the theoretical limit of measured performance, whether at whispering levels or at full power.

In common with previous generations of NAD Hybrid Digital technology, but unlike most class D amplifier designs, the M28 is impervious to the speaker load presented to it, maintaining the same wide and uniform bandwidth response regardless of speaker impedance while at the same time providing high current capability. The 200W continuous into 8 ohms for all channels driven simultaneously and 700W dynamic power into 4 ohms attest to this.

Inherent to Eigentakt technology is its very analog-like behavior in the unlikely event that the amplifier is driven into clipping. While many class D designs can become unstable, Eigentakt behaves in a manner similar to the benign clipping with instant recovery of well-executed traditional class A/B amplifiers.

The sonic character of the M28 only reinforces the story told by the numbers. This is an incredibly powerful and transparent amplifier bringing new levels of refinement and dynamics at all levels.

Fully Balanced Audio The same efficient audio interface used by studios offers the highest level of signal integrity with the lowest noise floor.

Lockable connectors and special interface electronics allow long cable runs without noise pickup or signal loss. All you get is impressive sound with no chance of noise pickup or interference.

As our most powerful amplifier to date, the M28 can pump over 700W into difficult loads to track complex dynamic peaks in your movies and music. Everything from rim shots to asteroid explosions sounds remarkably real and immersive.

The M28 has power reserves to meet the demands of the latest high-resolution digital soundtracks. Thanks to advanced Purifi Eigentakt amplification technology, all this monstrous power costs far less than traditional technology and delivers more power and performance!

Documentation

User manual Technical data sheet

Technical Specifications

Power

FTC Power, Two Channels

≥ 220 W (Nominal THD, 8 Ω, 20 Hz - 20 kHz, two channels driven)
≥ 400 W (Nominal THD, 4 Ω, 20 Hz - 20 kHz, two channels driven)

Rated Power, All Channels

≥ 200 W (Nominal THD, 8 Ω, 20 Hz - 20 kHz, all channels driven)
≥ 340 W (Nominal THD, 4 Ω, 20 Hz - 20 kHz, all channels driven)

IHF Dynamic Power

280 W at 8 Ω (all channels driven)
560 W at 4 Ω (one channel driven)

Audio Performance

Distortion and Impedance

THD ≤ 0.003% (250 mW to rated power, CCIF IMD, DIM 100, ref. 20 Hz - 20 kHz)
Input sensitivity: 1.3 V (nominal rated power)
Input impedance: 47 kΩ (balanced), 23 kΩ (unbalanced)
Damping factor: > 750 (ref. 8 Ω, 50 Hz and 1 kHz)

Frequency Response

± 0.1 dB (ref. 20 Hz - 20 kHz)
-2.5 dB at 3 Hz and 100 kHz

Signal-to-Noise Ratio

Balanced: > 102 dB (A-weighted, ref. 1 W), > 124 dB (A-weighted, ref. nominal power)
Unbalanced: > 97 dB (A-weighted, ref. 1 W), > 120 dB (A-weighted, ref. nominal power)