Its inputs, referred to as “Enjoyment Sources,” are numbered from one to six. This isn’t due to a lack of originality but with the modular input design: Among these, three inputs offer the choice between Zeel 50-ohm BNC and RCA connections. For the latter, a six-decibel attenuation switch can also be engaged. Additionally, the preamplifier includes a standard XLR input and two customizable inputs based on customer's preferences, which can be configured as balanced, unbalanced, or MC phono inputs. The “Standard” configuration of the NHB-18NS already includes one MC input. My test unit, however, was equipped with two MC inputs, increasing its cost by 10,000 Euro to 75,000 Euro. With a two-way toggle switch on the phono input, you can not only choose between normal RIAA equalisation and one with the so-called Neumann constant, and switch on a subsonic ic filter, but also to adjust the amplification in six three-decibel steps between 57 and 72 decibels and the load impedance in six steps between 43 and 300 ohms. Even without menus with the corresponding software and a lot of processor power, the darTZeel preamplifier proves to be extremely flexible.

On the output side, the NHB-18NS also leaves you spoilt for choice: in addition to a RCA and a XLR socket, there are also three BNC connectors with 50 ohms for connecting to darTZell power amplifiers, making bi- or even tri-amping a breeze. Since Hervé Delétraz owns various Revox and Studer tape machines, he has also provided his preamplifier with a tape output, unfortunately only an unbalanced one with a RCA socket. On the other hand, the effort put into the power supply is all the greater: in the front part of the preamplifier, which is designed in a double-mono construction, under a red anodised cover with the writing ‘darTZeel – The never heard before experience’, there are batteries that are charged by an external power supply unit, which is also excellently manufactured in the characteristic company colours.

The power supply for the power amps is integrated into the very elaborately designed power amp, and it would not be an exaggeration to say that the circuits are arranged around the power supply. The enclosure of the NHB-108 is divided into four sections, two per channel. The two 300-watt toroidal transformers are located behind the front panel. The comprehensive operating instructions, with their detailed explanation of the development of the power amplifier, state that the transformers were wound on 450-watt cores to prevent them from saturating. The primary windings are electrostatically shielded from the secondary windings so that no high-frequency interference is transmitted. The transformers are mounted on a so-called ‘false’ base plate and placed on rubber dampers so that practically no vibrations are transmitted to the circuits. The 20-millimetre-thick plate with the transformers is located a short distance from the five-millimetre-thick base plate that is visible from the outside. All cables and lines are routed through the space in between, minimising electromagnetic interference.