Now the company is wandering much deeper into traditional two-channel territory with the EA13, a 39-pound tube amplifier using four EL34 output tubes, two NOS Sylvania input tubes, mechanical VU meters and custom output transformers. Output transformers are among the most critical components in a traditional tube amplifier because they have to match the high impedance of the output tubes to the much lower impedance of the loudspeaker without compromising frequency response, increasing distortion or wasting power.