darTZeel Audio NHB-108 - Manual (Page 15)

darTZeel NHB-108 model one Audiophile's technical manual Page 15 of 28
5.4. Symmetrically balanced?
The following could seem contradictory
sometimes. It is mainly due to the terms
"balanced" and "symmetrical", or "un-
balanced" and "single ended".
In French, these terms lead to even
more confusion, since both "balanced"
and "symmetrical" are translated by
"symétrique".
So, you will not feel less comfortable
than our French-speaking friends. Feel
free to contact us at [email protected] if
you need explanations in greater depth.
It is absolutely fascinating to note that
some technical choices only serve falla-
cious sales arguments, and to our regret,
audio is no exception to the rule…
Most high-end power amplifiers, espe-
cially flagship models, offer balanced
inputs, described as being the very best,
technically and sonically speaking. As
often as not there’s no option as regards
balanced inputs: in fact there’s nothing
else!
For the darTZeel NHB-108 model one, our
approach has been almost the opposite.
To minimize the cost? Could you even
believe that?
Maybe the time has come to refresh our
memory to some extent…
5.4.1. From the microphone…
A balanced line is in fact a transmission
line without reference to ground. Imag-
ine that instead of transmitting the sig-
nal between one wire and ground, we
use two wires. A 3
rd cable, earmarked for
ground, is of course also present, even
though not necessary for the signal right
now.
This transmission mode finally leads to
external noise and disturbance cancella-
tion.
In pro audio engineering, balanced lines
are de rigueur and massively used. Un-
balanced links are very rare indeed! The
reason is very easy to understand:
Microphones generate very tiny electric
signals, and very long lengths of cable
run from the studio to the mixing con-
sole. In these conditions, it is primordial
for the signal to be free of any hum
and/or noise.
Also, in concert performances, mixing
consoles are generally located quite far
from the stage, and balanced lines are
welcome. A technical trick, using that
3
rd , ground wire, also makes it possible
to carry the phantom power supply feed-
ing electrostatic microphones.
So now you have understood that bal-
anced links are used especially in profes-
sional applications.
5.4.2. To the loudspeakers…
Let us quit the studio and come back to
the high-end, musical world.
Basing themselves on what they consider
to be the real benchmark, audio compa-
nies equip their flagship machines with
the balanced lines described above, us-
ing the well known XLR connectors.
Most of the time they offer "fully bal-
anced" topology from input to output,
claiming that the sound will remain unaf-
fected since it is immune to external dis-
turbances.
Technically speaking, fully balanced to-
pology is relatively easy to achieve. It
suffices to double the entire electronics,
in a mirroring fashion, assigning a new
channel path for the inverted signal. Of
course this simplicity has a price, in fact
double the price. Finally, the balanced
signal is amplified and routed to the
loudspeakers.
Come to think of it, are loudspeakers
balanced or not balanced? That is the
question!
5.4.3. And into the air…
Once in the air, the musical signal is
traveling on its last trip before delicately
tickling your eardrums.
How exactly does music propagate itself
in the air?
Music is a matter of vibration, and
propagates in the shape of waves. Any
wave, to be propagated, needs a me-
dium. No medium, no wave, no sound.
Just try playing trumpet on the Moon.
Not an easy task, even if your name is
Armstrong…