L-5000 DHT (Direct Heat Triode) Linestage

In the early years of the last century, the directly heated triode was invented independently, and almost simultaneously, in the USA and Austria. This simple device, an anode, cathode and a grid in a vacuum contained in a glass bottle, transformed the world. With all the applications in which it has been employed, and with all the changes in electronic design for audio reproduction that have occurred since its invention, it is remarkable that over one hundred years later, the very first triode, the simplest vacuum tube audio signal amplifier, despite the imperfections ascribed to it, remains a favourite audio amplification device of many devoted music lovers worldwide.


The Allnic L-5000 DHT is the world’s first commercially produced, pure DHT preamplifier. Currently, the L-5000 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-5000 DHT preamplifier. ONLY A LIMITED NUMBER OF UNITS OF THIS DESIGN WILL BE MADE.


The L-5000 DHT has the following features:


  • Line output transformer coupling – The L-5000 DHT 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 about10% of wattage – voltage is not affected).
  • 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.
  • No negative feedback design
  • Advanced tube technology voltage regulation – For quieter and more dynamic operation, the L-5000 DHT has an ultra-high speed automatic voltage regulation circuit, utilizing vacuum tubes.
  • New vacuum tube damping technology – Allnic Audio’s patented "Absorb GEL tube damper" technology prevents harmful vibrations from reaching the signal / gain tubes and, therefore, prevents micro-phonic noise propagation in the tubes. Provided other tube components do not introduce micro-phonic noise into your system, with the Absorb Gel damping system, you will enjoy a degree of transparent sound that will surprise and please you.
  • Precision attenuator volume control – The L-5000 DHT does not employ a digital IC volume control or a low-cost carbon film volume control with a motor. Allnic Audio has developed a precision oil clutched motorized attenuator; the L-5000 DHT has no (± 0db) channel unbalance at any volume level.



Read a review of the L-5000 here


Price $27,350 inc GST


Click here to view the Product Manual and specifications.


>Contact us for purchase information or if you would like to experience any of our products in person.