The HP205D is Icon Audio’s flagship valve headphone amplifier, based on directly heated triodes (DHT). At the heart of the design is the 205D valve dating from the 1920s — a circuit regarded as one of the simplest and most linear in headphone applications. The result is a sound of outstanding clarity and naturalness, awarded „Headphone Amplifier of the Year 2021” by Hi-Fi World magazine.
The 205D output valves (300B or Psvane 205D-L operation is possible) are driven by ECC88/6922/6DJ8 triodes, and the power supply is rectified by a 274B valve (or GZ34/5AR4, 5R4) for the smoothest, most analogue character. Headphone matching covers a 16–600 Ω range.
The unit is entirely hand-assembled, point-to-point, with no printed circuit boards. Available circuit and capacitor upgrade options, plus optional Bluetooth, allow it to be tailored to the individual needs of the most demanding listeners.
| Output valves | 205D (or 300B / Psvane 205D-L) |
| Input valves | ECC88 / 6922 / 6DJ8 |
| Rectifier | 274B (or GZ34 / 5AR4 / 5R4) |
| Power | below 1 W |
| Headphone matching | 16 – 600 Ω |
| Input sensitivity | 350 mV |
| Signal-to-noise ratio | −90 dB |
| Frequency response | 20 Hz – 20 kHz (+0 / −0.2 dB) |
| Power supply | 230 / 240 V, 36 W |
| Dimensions (W × D × H) | 160 × 270 × 160 mm |
| Weight | 7 kg |
Flagship valve headphone amplifier on directly heated triodes (the 205D valve) — hand-wired, valve rectifier, 16–600 Ω matching. Headphone Amplifier of the Year 2021.
