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Hypex FA251 or FA501 used as power-amp for bi-amping
Copyright 2020 © Troels Gravesen

An easy way to operate your speakers by bi-amping is to use the Hypex FA251 or FA501 as a power amplifier without any use of the DSP facility. As least for a beginning. Later it may be advantageous to add a little bass lift at e.g. 30-35Hz - and for vinyl lovers, a 2nd order high-pass section at 20 Hz helps greatly protecting your speakers and power amplifier for any very-low frequency accidents.

It goes without saying you need a pair of speakers with bi-wiring/bi-amping terminals. That is FOUR binding posts, two for mid-tweeter and two for bass. This means the crossover is have separate boards for the two sections. Usually this is done for bi-wiring, having one pair of wires for mid and tweeter and one pair of wires for the bass.



You connect the bass section to the Hypex module like described here: http://www.troelsgravesen.dk/FUSION_FA251.htm at bottom of page.

 

 

 


This is how it technically looks.
The Hypex gets it signal from speaker terminals; high-level input.

 


With the program for download here, the gain knob should be in the middle, click position, to match your power amp.


Had some oak leftovers and made a pair of boxes with speaker terminals.


Here the FA501, blue+red for PLUS and grey+black for MINUS.

Download software here. Unpack zip file on place folder in FilterData in My Documents.


Preset 1 with flat response and sub-filter.

Preset 2 with 3 dB lift @ 35 Hz and sub filter.

Preset 3 with 6 dB lift at 35 Hz and sub filter.