Siel Opera 6 + Siel Expander: a 12 voices 4 osc stereo analog polysynth

video upload by ohm-studi-ohm

"Well I confess the title is a bit misleading as this is not truly a 12 voices 4 osc stereo analog polysynth but rather 2 identical 6 voices 2 osc analog polysynth.
Indeed the Expander is the desktop version of the Opera 6 (also rebranded as the DK600 and Kiwi). Exact same motherboard and analog board (that explain the quite big footprint of the Expander).
They were however meant to be complementary, the Expander being control-less and without any editing possibilities, the only way to program it was to use an Opera 6 to dump patches to it.
But nowadays thanks to Tauntek's Expander firmware you can access all synth parameters by MIDI Control Change and with the help of your favorite MIDI controller you can have the equivalent of an Opera 6.
Still, playing the two synths together is quite a treat. The Expander can respond to Program Changes (stock firmware too) and thus with identical sound set you can recall the same sound on both unit by dialing in the program number on the Opera 6.
Furthermore the Opera 6 offers a split mode (when recalling preset 97 and validating 01, split point is assignable) so you can get 2x 6 voices identical sound on the left and right part of the keyboard. Not a proprer 12 voices synth but still it gives some polyphony headroom.
In the demo I hard panned both synth, this also has the benefit of giving a nice stereo image as both synth being analog by nature will not sound exactly the same. Especially by slightly detuning both units.
Most part of the demo sounds are layered but i do quickly demo splits at occasion.
Recorded dry, no fx, no EQ."