darTZeel Audio NHB-108 - Manual (Page 5)

darTZeel NHB-108 model one Audiophile's technical manual Page 5 of 28
darTZeel NHB-108 model one
Audiophile's technical manual
1. Introduction
Thank you for studying this manual,
demonstrating proof of your interest in
the darTZeel NHB-108 model one.
First of all, please do not think for a
minute that we consider audiophiles dif-
ferently from music lovers. We know
perfectly well that audiophiles love music
too, and we are very happy with this.
It is however true that music lovers are
generally less inclined to enjoy the tech-
nical and performance side of the music,
hence the existence of the Music lover's
manual.
In the light of what follows, you will bet-
ter understand why our technical choices
during the design of the darTZeel NHB-108
model one led to what one could call a
truly exceptional machine.
We trust that you will derive great pleas-
ure from reading this manual, and that
we succeed in communicating some of
the burning passion that has been boiling
inside us for more than 25 years.
Enjoy your reading!
2. Genesis of NHB-108
The NHB ("Never Heard Before") project
began in summer 1984.
Crazy about audio since childhood, we
gradually developed the idea of design-
ing a power amplifier.
Even though the NHB-108 model one is the
fruit of a single man, the moral, financial
and professional support from family and
friends over all these years has played a
huge part in this endeavor.
At the time it was only a dream, and we
are grateful to every gal and pal who has
been involved in it and contributed to its
achievement.
In the '70s and ‘80s, here in Europe,
Japanese electronics were queens and
kings of the market. Very rare, and
above all virtually unknown, was the real
high-end audio gear coming from USA or
elsewhere. The finish was already very
good, but the sound quality did not come
up to scratch, simply because it was not
one of the original design goals! Only a
few companies were able to offer real
breakthrough products. Not all of them
are still in business, Alas!
The more the years passed, the more
our desire for designing a new machine
became tangible. In mid spring 1984, we
produced a first digital power amplifier in
a school lab, as a diploma project.
Paradoxically, the innovation here was
not the fact that the amp was digital, but
that no feedback whatsoever was used.
The output stage was totally open-loop.
The sonic result was so astounding that
we immediately started the NHB project,
although its code name did not come
until later.
The initial idea was to design a new very
powerful digital amplifier, totally open
loop if possible, with the purest sound
reproduction we could attain, without
any other consideration, especially the
price factor.
The main problem at the time was that
the technology did not yet offer the
monochip solution, so we had to build
the circuit entirely in hybrid technology,
using mainly discrete devices. The odd
thing is that even in this early 21 st cen-
tury, we have still not surpassed the
speed of those old circuits.
Another problem then arose. Our circuits
were much more complex than a single
modern IC, and of course they were not
very reliable either. We especially en-
countered several performance consis-
tency problems from sample to sample,
and we gave up for a time. Some years