ALLNIC AUDIO L-6500 Kullanıcı El Kitabı - Sayfa 4
Amplifikatör ALLNIC AUDIO L-6500 için çevrimiçi göz atın veya pdf Kullanıcı El Kitabı indirin. ALLNIC AUDIO L-6500 14 sayfaları. Line-stage preamplifier
INTRODUCING THE L-6500 LINE-STAGE PREAMPLIFIER
Immerse yourself in the original recorded space. The L-6500 is a single gain stage, transformer-
coupled, remote-controlled line-stage pre-amplifier.
The L-6500 is silent, except for the music emanating from the blackest of backgrounds. The
outstanding sonic quality is matched by the simple elegance, flexibility and ergonomic
functionality of the casework and connection options. Few pre-amplifiers can compete at any
price.
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.
The L-6500 has the following features:
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Line output transformer coupling – The L-6500 is "transformer coupled. In tube amp
circuitry, there are two coupling methods; one is capacitor coupling and the other is
transformer coupling. Capacitor coupling is the traditional, low cost method. It is somewhat
stable but transfers only voltage, not wattage (i.e., not real energy). With transformer
coupling, about 90% of real wattage is transferred (there is still a transformer loss of about
10% of wattage – voltage is not affected).
Transformer coupling is superior to capacitor coupling. However, all the advantages of
transformer coupling depend on the quality of the transformer and on the choice of tubes.
Allnic Audio manufactures its own transformers and uses what it views to be the best core
material, Permalloy. Allnic Audio's unprecedented, wide (16Hz ~ 75kHz, -3db), low
distortional, and ultra-flexible (up to 50kHz square wave response) output transformer helps
Allnic Audio to realize the ideal transformer coupled preamplifier. Of course, gain tubes are
also carefully selected for three critical factors for function with the Permalloy output
transformers: high gm, low internal resistance and high mu.
Constant and low output impedance – One of the benefits of transformer coupling is that it
facilitates constant low output impedance. Low output impedance is critical to the design of
a good preamplifier. The L-6500 has a 150 ohm (150Ω) constant output impedance at all
frequencies. In capacitor coupling (C-R coupling), a "cathode follower circuit" is usually used
to lower output impedance. Unfortunately, this method of lowering output impedance is
accompanied by high distortion and has an "L" shaped output impedance curve. Please
compare the two graphs below, especially for low frequency response.
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