ALLNIC AUDIO L-9000, Руководство пользователя

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INTRODUCING THE L-9000 OTL/OCL LINE-STAGE PREAMPLIFIER
Immerse yourself in the original recorded space. The L-9000 OTL/OCL (Output Transformer-
Less/Output Capacitor-Less) is a triple gain stage, remote controlled, line-stage preamplifier,
without transformers or capacitors in its single-ended signal path. It uses the 6080 double triode
as its directly coupled output power tubes; i.e., there are no output transformers on the single-
ended (unbalanced) RCA outputs, so the 6080s communicate the signal directly to the connected
power amplifier or amplifiers, fully revealing the 6080s’ inherent accuracy and beauty.
In common circuits, output capacitors or output transformers are required to separate the AC
music signal from the DC operating potential. If this is not done, the latter will destroy the power
amplifier, the loudspeakers, or both. However, these two coupling devices also introduce their
own influences on the transmission of the musical signal, adding their own character
(colouration), increasing distortion, and consuming small signals, all as predicted by physical
efficiency theory. In addition, they also limit signal dynamics. For these reasons, the elimination
of output transformers and capacitors has been considered the best solution for the design of
the most accurate amplifiers. Removal of these two coupling devices from the signal path
achieves the best results possible:
•
No colouration of the musical signal
•
Extremely detailed expression, natural harmonics and subtle musical decay
•
The lowest possible distortion
•
The widest musical dynamics
In the L-9000, there is no coupling device between the preamplifier and the power amplifier; that
is, the final gain/output tubes are directly connected to the power amplifier. Thus, the benefits
listed above are fully present in the Allnic L-9000 preamplifier.
Some circuit experts might be concerned about DC potential in the music signal in an OTL/OCL
design. However, the chance of this problem occurring can be essentially and reliably 100%
mitigated. To do this, Allnic uses a “floating power supply circuit”, a design that deals with the
issue by not creating any DC potential in the first place, or such a small potential that it is
harmless.
The L-9000’s OTL/OCL circuit is basically SEPP, “Single-Ended, Push-Pull”, so a “cancellation
circuit” is required to adjust the balance of signal between the upper and lower power output
tubes’ input grids. Allnic uses an extremely sophisticated “Active Balanced Positive and Negative
Feedback Circuit”, in which the 6AN8 pentode perfectly controls the circuit’s operation with
extremely low distortion and incredible speed.
The L-9000 OTL/OCL is a world-class, reference level, line-stage preamplifier. It offers
unbelievably realistic, holographic sound-staging combined with incredible resolution, clarity,
micro-dynamics, and drive. Instrument and vocal tones and timbres are breathtakingly lifelike,
and the placement of instruments and bodies in three dimensions startling, life-size, and
addictive. The L-9000 OTL/OCL has no voice of its own, none. It is silent, except for the music