EHP-O2 Portable Headphone Amplifier
The EHP-O2 is a battery powered, portable headphone amplifier. The electronics have been designed by blogger NwAvGuy. The amplifier measures superlatively and they speak for themselves when describing the quality of the amplifier. This has been achieved by very careful component selection, taking advantage of their specific performance characteristics as well as shrewd electronic engineering.
It comes equipped with 2 rechargeable NiMh batteries for portable use as well as an AC adaptor for desktop use and charging purposes.
A built in gain switch allows the user to choose the appropriate gain for the source and headphones/earphones being used.
The EHP-O2 has:
1 x 3.5mm input jack
1 x 3.5mm output jack
1 x power inlet
1 x gain switch
The electronics in the EHP-O2 were designed to offer superior performance in every key specification possible. A snapshot of the measurements are:
THD @ 1kHz: 0.0017%
Noise level (ref 400mV): -105dB
Power output @ 33Ω : 641mW
Channel balance 0.6dB
Battery life: 8 hours
The EHP-O2 portable headphone amplifier is hand built in the UK.
DIY Builders: Unassembled PCBs are available for DIYers to build the EHP-O2 themselves.