darTZeel NHB-108 model one
User Manual, version B 1.0
Page
27
of 35
The medium can also be
steel
. The hammer hitting
the string, in a piano, generates a pulse which cre-
ates a propagating wave
in
the string, making it
vibrate. Then this vibration will be eventually
transmitted into the air.
Air: this is the ultimate medium where man-made
music propagates. Music is spread in wave form,
the latter being described by a physical law, called
"wave propagation theory". We will not enter into
the details, but mention just one crucial and essen-
tial point:
Acoustical waves do not
move
air.
When we read in some high-end magazine that such
and such a flagship loudspeaker can blow out a
candle while reproducing a trumpet or a saxophone,
this is just metaphorical.
The sound is produced by the
vibration
of air mole-
cules, step by step. Yes, you did read correctly. It is
vibration
, not
movement
.
If you know a friend who plays trumpet or saxo-
phone, just put your hand on the bell and you will
only feel vibration, not a single tiny puff of wind.
By the way, you would never think about a piano
being able to stir up air to produce wind, would
you?
These vibrations have a purely single-ended behav-
ior, since they are produced around a point of equi-
librium, where vibrations are zero.
To cut a long story short, we can say that the whole
acoustical chain is single-ended. The only moment
when the acoustical signal could be balanced is
when it travels into the electric wires. In the air,
sound is unbalanced, asymmetric, single-ended, as
you prefer.
Why then, this obsession to balance a naturally
unbalanced signal? Is it not against nature?
Furthermore, where is the real advantage in running
the loudspeaker in balanced mode? To our knowl-
edge, there is
no
balanced crossover in the market!
Has any manufacturer already told you that there is
no such thing? Okay, now you’ve been told.
T5.4.4. Via the darTZeel
In the version
B
of the
darTZeel NHB-108 model
one
, we have also installed balanced inputs. Did we
do this just in order to be “with it”?
First, we want to stress that we use
floating
bal-
anced inputs. This means that rather than doubling
the whole electronics, as seen above, we use high
quality input transformers. Of course the use of
transformers is much more expensive, but the re-
sulting performances are far superior.
Speaking of external disturbance immunity, trans-
formers are much better than full active balanced
topology. The common mode rejection (this is the
name given to that kind of immunity) can be – wait
for it – no less than
five thousand
times better when
using transformers instead of full balanced circuits.
Another, unbeatable, advantage is that they offer
true electrical isolation – called
galvanic isolation
–
between the line and the gear, providing out-
standing safety in professional use. Last but not
least is the fact that all the above-mentioned quali-
ties are defined at the building stage, meaning that
performances will not decrease over the years or
even decades to come. This is not by any means the
case in full active balanced versions.
In conclusion, we cannot resist insisting on the fact
that a full active balanced solution utilizes twice the
number of components, implying a more complex
signal path, less reliability, and furthermore, espe-
cially in power amplifiers, an output impedance
twice as high
as with single-ended topology, and
requires a higher output stage NFB to compensate.
Now that you have read these simple but demon-
strative explanations, do the words "full active bal-
anced" still mean "absolute superior sound" for
you?
All this explains our choice for using, as a matter of
course, transformers of the highest quality for our
XLR inputs in the version
B
.
We said above that by very nature, music is part of
a single-end world. More than 100 years ago, de-
signers chose floating balanced lines – full balanced
was not ready yet – for long distance links for the
sole purpose of minimizing external disturbances.
Electric signals were therefore transmitted in a bal-
anced way, the equipment working in single-ended
mode.
The
NHB-108 model one
version
B
offers this
very same possibility to professional users wanting
to link their remote consoles to the NHB-108 model
one, without having to use poor quality Balun-DI
devices.
Despite what all our esteemed competitors might
think, we nevertheless assert
and
corroborate that
the one and only means of processing, amplifying
and broadcasting a musical signal without altering
it, even in the slightest, is simply to use the single-
ended mode.
But only in a special way, though…
With short cables, say less than 10 meters, symmet-
rical - balanced - transmission does not have any
justification but marketing. A given gear "singing"
better in balanced mode only reveals poor design in
some part of the circuit, which can be partially
masked by internal disturbance cancellation.
