The LA5 TX is an exceptional valve line preamplifier with a transformer output — with no capacitors in the output path. Instead, the signal leaves the unit through proprietary Icon Audio transformers, which according to the manufacturer gives ideal system coupling, free of the „mechanical” character of solid-state electronics.
The 6SN7 valves work as an input buffer, providing a constant, high impedance for the source — so the transformers work in optimal conditions regardless of the connected equipment. A low output impedance (250 Ω) and a balanced output allow long runs with no loss of quality. A GZ34 valve rectifier (or 274B / 5AR4) completes the calm, smooth sound.
The design is entirely hand-assembled, point-to-point, with a power supply regulated by a dual choke and DC valve heating. Inside: a motorised ALPS Blue potentiometer (optional stepped attenuator), Solen/SCR capacitors (Mundorf option), 2 W resistors and silver-plated PTFE wiring. Intended for top-class valve and solid-state power amplifiers.
| Valves | 2× 6SN7 (CV181) |
| Rectifier | GZ34 (or 274B / 5AR4) |
| Transformers | proprietary Icon Audio output transformers |
| Gain | 3× (7 dB) |
| Max. output | 20 V (at 6.66 V input) |
| Output impedance | 250 Ω |
| Signal-to-noise ratio | −90 dB |
| Frequency response | 20 Hz – 15 kHz (+0/−0.5 dB); 7 Hz – 28 kHz (+0/−3 dB) |
| THD distortion | below 0.18% (0.5 V output) |
| Inputs / outputs | 4× line; balanced output + RCA; recording loop |
| Power supply | 220 / 240 V, 75 W |
| Weight | 18 kg |
Valve line preamplifier with a transformer output (no output capacitors) — balanced output, 6SN7 triodes, hand-wired assembly. The purest system coupling in hi-end.
