Representing the top of the line in LAMM hybrid and solid-state audio equipment, the L2.1 Reference is the result of years of intensive research to secure the most accurate reproduction of recorded music. Unique topology and application of the most advanced technological resources and processes bring the L2.1 Reference near the threshold of excellence in sound reproduction.
A main distinction of the L2.1 Reference—when compared to other preamplifiers—is its nearly inaudible sonic signature. When connected to the right LAMM power amplifier, it allows for extraordinary transparency of perceived sound and the recreation of a three-dimensional soundstage in the home—providing recording studio quality in the comfort of your living room.
The L2.1 Reference features a sophisticated design and topology that brings out the most natural sound performance in the audio pathway. Its unique circuitry utilizing specially selected, super-linear, high voltage MOS-FET transistors ensures a class A operation from input to output, with no overall feedback at any stage. All stages, including high current output buffers, are single-ended. A distinctive electronic protection circuit enables manual muting of the outputs until the preamplifier has stabilized after a turn-on; it also enables functioning of the preamplifier in a “muting” mode during operation and automatic switching to muting in case the AC line voltage drops or is interrupted.
Other features include 3 inputs; 1 tape loop; output signal phase switch; balanced and single-ended outputs; and built-in remote on/off for LAMM power amplifiers.
The L2.1 Reference has a separate power supply that utilizes a choke contained filter, vacuum tube rectifier, and voltage regulator.
Special care was taken in designing a high-voltage (+350V), high-speed, vacuum-tube voltage regulator. Using this voltage regulator, in conjunction with other technical aspects, enables the reproduction of smallest nuances and three-dimensional subtleties in the music palette (provided that such details were not lost in a recording process). A somewhat unusual combination of high-voltage, vacuum-tube power supply and superlinear, high-voltage MOS-FETs allows it to attain an enormously large output swing, while retaining nearly constant harmonic contents of the signal with an absolute dominance of the second harmonic.
Design-wise, special attention was paid towards optimizing the output impedance of the preamplifier to attain almost full independence of the output impedance from frequency, while allowing the preamplifier to drive (without audible sonic degradation) significant capacitive loads created by many modern interconnect cables.
Each preamplifier is carefully hand-crafted the highest quality materials, including military grade low noise Dale metal film resistors; unique TKD stepped potentiometers (41 detents); PRC wire wound resistors; Electrocube and Roederstein film capacitors; high frequency switching grade Cornell Dubilier electrolytic capacitors; specially selected long life vacuum tubes; high quality heavy duty gold-plated RCA connectors; and gold-plated Neutrik XLR connectors. The preamplifier power supply features a custom-designed super-low noise toroidal power transformer. AC voltage is filtered by a special RFI power line filter.
In creating a preamplifier with practically no sonic signature, we do take into consideration the fundamental limitations inherent in reproduction of live music by electronic means.
The L2.1 Reference works on all world AC line voltages (100/120/220/230/240V).
The following measurements of the L2.1 Reference were performed by the late Bascom H. King
M1.1 or M2.1 or ML2 or ML2.1