NHB-108 Model Two Power Amplifier

The NHB-108 was the first power amplifier designed and built by darTZeel.

1 Year




The NHB-108 has earned legendary status among critics and music lovers alike. Its immediate success and multiple awards helped to quickly establish darTZeel in the premium market.

Regularly updated over a number of years and now reinvented in a «model two» version, this ultra-rapid, dual-mono amplifier is the high-end offering in the NHB series.

With power output of 150 watts per channel and its circuits patented worldwide that prevent global negative feedback, the NHB-108 model two connects effortlessly with any type of speaker, unleashing its full magic and capability.

With two power supplies, two transformers, two audio circuits, and two coolers, the darTZeel model two is very much a dual-mono power amplifier in every respect.

The power supply cord is the only sign that everything is housed within the one chassis.

The NHB-108 is the culmination of two decades of research and development.

Hervé Delétraz meticulously explored the possibilities for reproducing music in all its emotional richness and splendour.

The end product is an electronic audio circuit that has been greatly trimmed back to offer exceptional simplicity, which no one before thought possible.

Hervé Delétraz holds the patents that have made development of the NHB-108 possible.

His universal circuit diagram forms the basis for all their products, before applying the little touches that make a darTZeel.

In the relentless pursuit of perfection, everything must be considered down to the slightest detail.

darTZeel amplifiers delight not only in terms of how they sound, but also how they look and feel.

Through its toughened mineral glass panel, one can admire the fine-brushed, crescent-shaped bus bars made from 24-carat gold and the carefully partitioned internal layout that gives this exceptional amplifier its unique character.


Nominal Output Power
150 watts RMS @ 8 ohms
225 watts RMS @ 4 ohms
Power Stage Gain

26 dB @ 8 ohms

Analog Input Impedances
BNC Zeel 50 ohms, 1 Hz to 1 MHz
RCA line > 30 kohms, 5Hz to 100kHz
XLR > 30 kohms
Speaker Output Impedance

< 0.33 ohms from 20 Hz to 20 kHz (measured under 8 ohms)

Frequency Response

0.8 Hz – 600 kHz, +0, -3 dB

Rise Time

< 0.8 µs

Slew Rate

> 88 V/µs, peak-peak

DC Output Voltage

± 50 mV

Total Harmonic Distortion (THD)

< 1 % from 7 Hz to 77 kHz within the output dynamic range

Temporal Distortion

None, at any level and load, as specified above


< – 90 dB from 20Hz to 20kHz

Signal to noise ratio

> 112 dB (A) @ nominal power

Power consumption

50 watts @ idle, 900 watts @ maximum output power

Size in mm

440 x 350 x 170 (WxDxH). Total deep with handles : 415mm

Size in inches

17.32 x 13.78 x 6.7 (WxDxH). Total deep with handles : 16.4 inches

Net weight
30 kg