Lowther PX4 Amplifier

Lowther is one of my favorite vintage audio companies. What they are doing is amazing. Their speakers especially. I just saw the PX4 and yes I am a little late to the show. That green and gold is a show stopper for me.

Amplifier topology:

PX4 Class-A push-pull

Valves fitted:

4 × PX4 (output)

2 × 6SN7

2 × 6J5

1 × 5U4G/5AR4

Bias arrangement:

Automatic cathode bias

Rated output power:

10 W + 10 W into 6 Ω

Frequency response (-3 dB):

10 Hz – 45 kHz

Signal-to-noise ratio:

93 dB

Input:

Main In × 1

Input sensitivity/impedance:

1 V rms for rated power / 300 kΩ

Variable feedback range:

0 dB – 10 dB (user adjustable)