8 Voices of legend
What happens when you take 8 mono synths and use them together? Huge analog sound! This sound is the result of slight imperfections between each voice card and, because of some electronic components (mis)behavior, parts from the orginal circuit (notably the OB-X) caused all sort of distortion happening at different stages from filter to VCA and also at the output stage, OB-Xtreme place a special
There is a lot to say about what V2 is, I can already say what it is not : a simple V1 cross-platform update. V2 is a full remake, while V1 was a simpler take on an OB voice card architecture, V2 is more closely related to original OB designs and specs (including features from OB-X, OB-Xa etc) it is not a direct V1 replacement, nevertheless it got a Legacy mode for Envelope Generators and Filter control so V1 sounds can be reproduced or made (more on that later).
V2 have higher specs in every part of the circuit, it comes as an upgrade gift to all V1 owners, V1 owners will get it for free or use a “give what you want” option.
Pre-Release main features
This pre release is the full functioning synth minus the v2 factory presets (only v1 bank + some extra are included until September) and LFO2 not active. This will be ready for final release in september 2022 which will come as a free 2.0.1 update for all owners of v2. Bare with me, trying to keep this summer release date as one man operation was THE WAR 🙂 at least you can already design sounds and funk it up with some Brass Stabs, cutting leads, lush pads and screaming bass.
A complete list of OB-XTreme 2.0 features is provided below, in a nutshell OB-Xtreme can act as an 8 voice polyphonic, 8 voice unison mono or true (one voice) mono, a FAT mode engages the unison while also providing polyphonic unison, that means 8×8 voices power.
Most OB-X/OB-Xa functions are provided, including SAW, PULSE, TRI oscillators shapes and the peculiar SAW+PULSE which can produce an interesting +1 OCT harmonic depending on the pulse width setting.
the 2Pole filter is based on the OB-X and the 4Pole is based on the CEM3320 implementation, the 2pole has that classic SVF linear “singing” resonance accross the bandwidth while the 4pole will resonate less at lower cutoff values (a bit Moog like), a bandpass output is also provided in 2pole mode while 4pole have an optional volume loss compensation.
The Xtreme factor is the main control over the emulated OTA enduced distortion, one chip in particular the CA3080 was used a lot at different places in the circuit (although less and less over the OB synths evolution). OB-Xtreme gives some control over that, you can push them way beyond the original specs or stay at minimum for more traditional behavior, you can also bypass PRE or POST circuits for versatility. The PRE stage will act more on lower notes while the POST stage is linear across the range.
Another feature is the under the hood access so you can control the 8 voice cards voltages across the main parts. The cards variations are an important factor to mimic the analog character, while using a VCM (virtual component modeling) approach, I wanted something effective but not time consumming so I designed some pre-defined offsets and deviations that you can mix in or scatter accross all 8 voices.
You get five macro sliders: OSC (which doubles on the front panel as the “SPREAD”) controlling OSC 1 and 2 tuning offsets, FILT filter envelopes offsets, AMP for amplitude envelope offsets, VCF for VCF deviation and PW for pulse width offsets. Additionaly you can toggle a realtime small random deviation per note or randomize and scatter deviations around. voltages offsets reflect on the GUI as positive or negative voltages (yellow/blue).
I removed a not so usefull temperature function that changed the EG timing to make room for individual card tuning (will be featured in September update) so we can have a ressembling chord mode.