ILP Electronics Ltd. Hybrid Power Amplifier HY50 - Released 1973

Description from the time:

A brand new hybrid fabrication technique, recently perfected in our laboratories, has enabled us to achieve our latest range of completely integrated devices.
We have now finally reduced the modular amplifier to a simple input/output device requiring only the addition of a basic unstabilized (split-line) power supply.
The HY50 takes medium power modules to their logical conclusion by incorporating with it a heatsink, which is designed in special high conductivity alloy, sufficient for normal audio use without additional chassis sinking. All this without significantly increasing the size of the module comparable in size to a packet of 'King-size' cigarettes. Consistent with modern thinking a triple-rated output circuit with a load fuse allows for peak transient response without distortion but ensures the necessary protection.

Details:

Brand - ILP Electronics Ltd.

Model - Hybrid Power Amplifier HY50

Dimensions of 105 x 25 x 50 mm / 4.1 x 1 x 2 inch

Colour - Black

Potential applications - Low Power Disco, Medium Power HiFi Systems, and Guitar Amplifier.

Output power of 25W RMS into 8 Ω

S/N Ratio - better than 75 dB

THD - less than 0.1% at 25 Watts, typically 0.06%

Input Impedance - 47 kΩ

Input Sensitivity - 0 dB (0.775 V RMS)

Features - integral heatsink, only 5 connections, 7 amp output transistors, and no external components. It also has a Freq. Response of 10 Hz - 50 kHz, ±1 dB

Condition - New, mint condition item. Opened, never used. Some wear on the box from storage. (see pictures)