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heated triode stages. The L-5000 DHT preamplifier, predecessor to the L-8000 DHT, was pure
DHT - from input to output.
Of course, Mr. Park is not the only builder who has accomplished this, but to our knowledge no
other pure DHT preamplifiers have been commercially available. There are serious and
significant reasons why such preamplifiers could not be acceptable in the marketplace. First
among them has been the enormous problem of microphonics. One of the many special
elements of Mr. Park’s design is reduction of microphonic influence on the DHT’s. Where others
have sometimes accepted the effects of this problem because even with it they prefer the
incredible realism of the pure DHT approach, Mr.Park has succeeded in creating a circuit and
mechanical design that reduces the DHTs’ susceptibility to microphonic influence to
insignificance. Like the Allnic L-7000, which is an indirectly heated triode preamplifier, the L-
8000 has a noise floor that is effectively absent.
The Allnic L-8000 DHT preamplifier is the improved successor to the L-5000 DHT, which was THE
WORLD’S FIRST COMMERCIALLY PRODUCED, PURE DHT PREAMPLIFIER.
Currently, the L-8000 DHT’s large output tubes are very rare items, produced many decades ago.
Allnic has been able to secure a limited number of these valves, enough to produce an also
limited number of the L-8000 DHT preamplifier. ONLY A LIMITED NUMBER OF UNITS OF THIS
DESIGN WILL BE MADE. This allows for valve stock to be retained for replacements, should that
ever become necessary, something that is unlikely for a very, very long time – unless one drops
the tube! This is because the qualities of the valves combined with the circuit in which they
function will extend their life to the utmost limits, very, very much beyond 10,000 hours.
The L-8000 DHT is Allnic Audio’s next to the top of the line (L-10000) line-stage preamplifier.
Like all Allnic Audio products, it uses Permalloy (Iron and nickel alloy) for its transformer
cores. Allnic is grateful to Mr. G.W. Elmen of Western Electric for inventing Permalloy for
transformer core use, and in so doing, providing an enormous service to recorded music
listeners everywhere.
Another world’s “first of its kind” for Allnic Audio
61 STEP CONSTANT IMPEDANCE BRIDGED TYPE ATTENUATOR
Allnic Audio’s newly developed 61 step constant impedance bridged type attenuator, a world’s
first, is installed inside the L-8000 DHT, which contributes to the L-8000 DHT’s outstanding
dimensional sound. It does so by ensuring that the attenuator’s impedance is absolutely
constant across all frequencies. This is in addition to the zero channel imbalance, a standard
feature of Allnic’s in-house produced, motorized attenuators.
