The ecp audio L-2 is a single tube, parafeed, "spud" amplifier for dynamic headphones.
The L-2 uses a single high-mu, high-Gm tube for both amplification and output power. The L-2 does not merely use up-to-date parts, it is a thoroughly modern tube circuit design based on the culmination of years of experience. The L-2 uses modern solid state parts to help the tubes perform their best; better than previously possible.
For tube audio, the tradeoff has been liquid midrange versus the bass, speed, and punch of solid state. With the L-2, this tradeoff has been eliminated. Bass problems in tube amps are more of a circuit design problem than a tube problem. In fact, tubes are just as capable of amplifying bass signals as solid state devices. But most designers use tube circuit designs that are little changed since the 1930's. This is not the case with the L-2.
The L-2 uses cascaded MOSFETs to provide an extremely high load to the plate of the tube. This high impedance load provides more than 100dB of audio circuit isolation from the power supply. The L-2 also uses a novel bi-polar transistor shunt regulator to provide very low impedance and linear bias.
Additionally, the L-2 uses Lundahl mu-metal core input transformers. The input transformers act as balanced to single ended converters for balanced sources, while rejecting upwards of 120dBs of common mode noise. The result is an amplifier that renders the interconnects used nearly immaterial.
Headphones are extremely sensitive. Therefore, the best headphone amplifiers need to be extremely quiet. The L-2 excels at this. The L-2 is so quiet that, even with low impedance headphones, you simply cannot tell it is on. There is no noise, no hiss, no buzz, no hum -- nothing but silence.
All of this adds up to a very clean, fast, powerful amplifier with the liquid midrange that only a single ended tube amplifier can provide.
Each amplifier is assembled in the customer's choice of wood, and comes with a dedicated power supply.