That Oberheim Character!
You can hit the filter hard but it always sounds musical and never out of control
You might be thinking ‘what’s so unique about the OB-6’s sound?’ compared to its fellow synth brethren! Well, for most, it’s a combination of the vibey sounding oscillators with the very distinctive SEM-based ‘state-variable’ filter. While you can actually get pretty close to the OB-6 sound using other modern synths with 2-pole filters – for example the Andromeda and Roland JD-XA (although the JD-XA is only a 4-voice poly, in 2-pole, LPF3 mode you’ll be surprised how close it gets but watch your osc/resonance levels!) – there’s some subtle stuff going on in the OB-6 that you can’t quite emulate exactly, except perhaps on an older Obie (though the old OBs by their vintage nature are even more vibey and thick-sounding with more voices to play with too)!
While the oscillators sound great on the OB-6 (very similar sounding to the Prophet-6), the OB-6’s greatest assets are its filter/resonance, modulation facilities and mixer and the way these features interact. You can definitely hit the filter pretty hard to induce all sorts of subtle saturation and distortion (which adds what we’d describe as ‘wiriness/hairiness’ to the sound) but it always sounds musical and never out of control the way a self-oscillating filter does when pushed to extremes. The resonance reacts completely differently to a 4-pole filter and really bulks out the sound, while the extra high-frequency ‘leakage’ gives the resonance and filter something to chew on, resulting in thickening, boosting, more ‘air’ and liquefying of the sound without things going too wayward!
As we mentioned earlier, the nature of 2-pole filters is that they let through more high frequencies than a 4-pole LPF and consequently if you are making a pad (for example) and close down the filter cutoff for a warm pad, you’ll still hear some fizz/ sizzle leaking through – this means you can achieve warmth and clarity simultaneously but also gives you a unique texture that’s very different to the Prophet-6.
Of course, you can also move seamlessly between filter modes on the OB-6 (more on this later), but here we’re specifically talking about when the filter mode dial is firmly set to LPF only; it’s almost like having two filters in a single mode, though at the same time, if you want a very pure low filtered LPF sound with no HF ‘leakage’, the Obie filter isn’t necessarily your best bet – it definitely produces a very distinctive type of pad sound. Our favourite role for any Obie synth is brassy patches, ‘furry’ wide pads and characterful basses and many classic records have featured old Obies in upfront roles including main riffs, pads, leads and basslines. So without further ado, let’s explore more!