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The control of sound volume plays an important role in the sound quality
of audio amplifier. For solving this problem, Luxman makes efforts on studying
the problem of sound volume control from the point of view with sliding type
volume as topic. By applying the analog technology concerning the base of
music reproduction to an extreme extent, Luxman has developed ultimate
volume that could bring the highest purity. The analog volume control which
used to get a high evaluation for formerly installed in C-911 was built in C-8f.
The ultimate volume composed of the parts made of 4 connecting brass which
could match to the complete balance
circuit construction has achieved the
remarkable high precision and lower
distortion rate with its maximum
attenuation value at -“120dB and its
synchronization error under ±0.5dB
( 0 - 9 0 d B ) , a n d n o n u a n c e l o s s
occurred to the back ground of the
sound even when the sound volume
being small.
For the excellence of [f]. Controlling penetrating the center of music expression.
What is the existence meaning of control amplifier? Luxman has taken the pursuing for excellence of this topic as its mission and has poured its efforts and has poured its results in C-8f. The improvement of some basic functions such as input selection, sound volume control, etc. could offer
much sufficient energy to the signal sending to power amplifier than before, and could play a role as power amplifier drive to activate the music
expression. While continuing the pursuing for excellent purity music quality, Luxman has added innovative ODNF circuit and launched C-8f with an
intent for controlling the center of expression field. The "f" attached to C-8f meaning the "finest" tells you what is the target that the control amplifier
has been steadily pursuing for.
Collecting the analog technology to the extreme extent
gives birth to the 4-connected ultimate volume
Ultimate volume with high precision and lower distortion rate
The newly-developed ODNF circuit which could grasp
the moment when the music was played
Only by distinguishing the existence feeling of sound such as each violin,
viola, cello from the grandeur sounds of full orchestra, the rich sound excitement
could be gained. For freshly reproducing the nuance of each sound, efforts
should be made in pursing the speed of initial slewing rate which could catch the
moment when the sound was generated. In addition, to reproduce more natural
music, the smooth connection unified the sound colors covering the whole ranges
from lower end to the higher end is indispensable. It is the ODNF circuit that has
pursued the reproduction of music in a higher level, and aimed at fundamentally
reforming the relations between music signal and distortion. Luxman shall first
of all develop super-broad band·slewing rate and lower distortion circuit which
needs no phase correction be done for the amplification circuit part of music
signal. So the phase correction that has to be done in former negative feed back
(NFB) circuit could be omitted. In addition, the existence of NFB should be
paid attention too. For correcting the distortion of each music signal, the NFB
method so far has caused the limitation on band field and the lacking of music
information volume. Here, the distorted elements from output are fed back to the
final section of amplification circuit, and only the distorted elements are removed
from output waveform. Through the separating of NFB method from music
signal, the high speed of initial slewing rate generated at the moment and the
super-broad band field could be obtained. Furthermore, the DC servo amplifier
used in controlling super-lower band that is the factor offering un-natural color
ration to the lower band in NFB circuit could be removed. Thus the natural music
reproduction unified the sound colors covering the whole bands could be realized.
A power amplifier drive which could bring life to sound
When hearing the rich life feeling from the reproduction sound of system,
one can feel the existence of excellent control amplifier. For protecting the purity
of audio signal, there is a method to solve this problem by directly connecting
power amplifier to the CD player, etc. Thus one could feel the full expression of
leaping owned by the music by gaining a clear sound quality. To seek the music
expression full of life, it has to adjust the impudence of signal in the system
and to adopt the control amplifier which could enhance the energy of acoustics
up to the level of being able to drive power amplifier. In C-8f, the flat amplifier
composed of the circuits similar with that of power amplifier M-8f was built
in. The control function of audio signal could highlight the sound forum and
increase harmony than ever, and the functions displayed by power amplifier drive
for clearing each sound character has brought life to each syllable of sound.
ODNF circuit concept diagram INPUT OUTPUT
Main amplifier
Sub-amplifier
Distortionelements forcanceling
* Main amplifier: Non-NFB amplifier* Sub-amplifier: Only the differential elements of input and output and output waveform are amplified
(Only differentialsignal was amplifier)
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of custom-made parts. And the data and performance achieved through the
development of high sound quality parts by years efforts has given birth to the
Luxman special custom-made parts. For making good resistor, the studies on
the varieties of materials and methods from the selection of alumina used as the
porcelain material, to etching, carbonization, terminal material, terminal shape,
press-in method, etc. should be carried out on the basis of carbon film resistor
with excellent sound effects. For rapidly increasing the transferring volume
of information, the special resistor
which could reproduce the music
with rich expression was adopted.
I n a d d i t i o n , t h e c u s t o m - m a d e
p a r t s fi l l e d w i t h d e d i c a t i o n t o
t h e h i g h l e v e l t e c h n o l o g y a n d
s e n s i b i l i t y h e a d e d b y p o w e r
transistor, followed by electrolytic
condenser, copper styrol condenser,
copper-made bus bar, high purity
c a b l e , e t c . a r e a d o p t e d . I n t h e
fields of custom-made parts group that could be said the exclusive kingdom of
Luxman, you could enjoy all the sensibility
shown by Luxman on audio.
Giving a full play of the real value of complete balance
amplifier with high level know-how
The complete balance amplifier was adopted in C-8f. By adopting the
power source supply mode of S.T.A.R. circuit which has used the high grade
parts and taken the clear amplification reference point, the real value of balance
amplifier was given full play. The un-wanted elements occurred inside the circuit
will be cancelled effectively when output happened.
The high inertia power source following the drama with
ever-changing sounds
The changes of sounds vary from shrieking to noiseless. Mahler s
orchestra music featuring short-term fluctuation is nothing but a drama full
of ever-changing sounds. The high inertia power source supplying energy in
accordance with the fluctuation at every moment has liberated the leaping feeling
of the lively music as it was. The ordinary method carried out in controlling the
power supply in accordance with the music sound has become the controlling
lagged behind off the real time music, as well as has become the factor blocking
the leaping felling of music. The special electrolytic condenser with excellent
instantaneous discharge feature was built in the high inertia power. It has
created an environment which could pool an ample power, and minimizing the
delay control. It could supply dynamic power supply in a most natural mode to
amplification circuit.
The countermeasure aiming at completely eliminating noise
for thoroughly protecting the pure and stainless sound
It is a high rigidity and box-separating construction by adopting various
countermeasures against noise and un-wanted vibration. With the 5-points
earthing FRP chassis base which is excellent in the mode of absorbed oscillation
as the foundation, the parts are firmly fixed on the thick chassis, the case body
construction at heavyweight level keeping off the vibration noise was obtained.
In addition, by taking the layout with no direct interference with each other of
the power transistor, chemical condenser, amplifier block, and the separating
of these blocks with shield plates, as well as the strengthening of internal filter,
the flux and the interference of noise are cut down. The efforts dedicated to
improvement of the pure sound quality are extended to the construction of
power source. The power source part was separated by barrier construction,
and the independent power source room mode which was combined with
the body chassis by semi-floating processing was adopted. By isolating
electromagnetically and mechanically, the leaking flux within the same case
body could be shut out.
The special custom-made parts group provided by Luxman
is a "must" (product) for improving sound quality.
In the music, there hides a life of sound which was not yet heard by the
ears of human. Based on this confidence, for completely exploring the music
information hided in the source, Luxman has been dedicating itself to the
improvement of the reproduction at tiny level by adopting
Setting the "gain-1" position used
for multi-channel machine
A f t e r c a r e f u l c o n s i d e r a t i o n a b o u t
combining the multi-channel audio machine
such as the home theatre processor, etc. into
the main volume, the "gain-1" position was
newly determined. Thus the adequate music energy supply ability could be
given full display under the condition without losing the audio level balance of
each channel set by the processor, etc.
Making high grade design and finish intimate to music
It is a forum so intimate to the colorful music space. Audio amplifier is
pursuing such dignified beauty. The symmetrical design was adopted in C-8f
for removing the surplus performances. It is a slim and clean front panel. The
precise hair line processing that reflecting the grade of the articles of everyday
use could give you a legend of the high processing level in the internal
mechanical part.
