Up for sale is a vintage Harman Kardon HK725 pre-amplifier - fully working and in good condition

A high-end Japanese made amp from 1980 designed by Finnish audio guru Matti Otala, and putting into practice his research into transient intermodulation, and intermittent impulse modulation - the result is a sophisticated ultrawideband pre-amp that produces beautiful and dynamic sound - able to articulate complex tonal and harmonic information with superb stereo imaging and separation

Features an outstanding quality phono stage - itself comprised of 8 stages - the phono signal is equalised to match the RIAA curve - an inverse process required to restore the signal for accurate reproduction. The record cutting lathe magnifies treble information and minimises bass information in order to meet physical constraints of vinyl real estate on a record. Many phono stages roll off this curve below 20Hz and above 20,000Hz - here the equalisation curve is met above and beyond audible range - ensuring absolute fidelity with deep controlled bass and transparent highs

A great looking amp - slightly more compact than others - a matte silver front panel with an array of square button controls. These not only look great, but employ fixed resistors for tone controls rather than the standard design approach of potentiometers - this allows for true bypass in the defeat position.

Physical condition is nice - some wear to the top of the cabinet - the front panel looks good with minor blemishes

SPECS

Frequency response: 1Hz to 150kHz

Total harmonic distortion: 0.005%

Input sensitivity: 2.3mV (MM), 145mV (line)

Signal to noise ratio: 90dB (MM), 106dB (line)

Dimensions: 385 x 72.5 x 320mm

Weight: 4.2kg

Year: 1980