So one of the most beguiling things for me about the Super 6’s SSI 2144 filters is their self oscillation. I regularly run them into self-oscillation with DDS2 set to off via LFO mode whilst balancing DDS1 into the equation. I’m super glad there’s a dedicated DDS2 filter modulation slider as there’s so much mileage there with audio rate modulation. That’s perhaps for another thread on phasing sideband FX by slightly detuning DDS2 relative to DDS1 (remember we’re not hearing DDS2 directly, only its frequency modulating the self oscillation of the filters). However…
It occurred to me that by virtue of solely using ENV1’s Decay Hold parameter on the filter we can actually ping the filters with a gate rather than sweeping them. So last night I delved into what I understand about the technique as follows from init state:
- Set the mix knob fully clockwise
- Set DDS2 footage knob to LFO and the switch either all the way down or up (audio in). We’ll no longer hear anything when notes are triggered.
- Arrange ENV2 with a small amount of attack (say about 20%, less clicky than at zero) decay at zero, sustain 100% and release at 100%
- Ensure filter env modulation is set to use ENV1, 100% depth
- Arrange ENV1 A,D,S,R all to zero
- Set filter freq around 50%, then whilst playing some notes push the resonance to the brink of self oscillation. If you go too far then the resonance will ring out permanently due to the VCA envelope (ENV2) release being at max. At this point it’ll help if you perhaps turn the arpeggiator on but at a slow tempo so you get a constant rate of envelope triggering.
- Press shift and start to bring up ENV1 Decay Hold parameter. I think by now if you’ve set the resonance slider just about right you’ll have some pings going but you will need to balance it so the resonance isn’t ringing out permanently, go low and then bring it to the point where you’ve got some consistency with the pings.
- This is optional but seems to help force the filter into excitation; In the modulation matrix you can route ENV1 to Resonance and set the depth to 100% so that resonance is maxed when the envelopes are triggered but is then immediately cut out leaving the filter to ring by itself without a secondary resonance offset.
- Well I think we should be in the land of ping by now
You can adjust the filter frequency slider to choose the base frequency of your pings.
What next?
Well the first thing I tried was setting the key tracking to full. Although in normal self oscillation (assuming you’ve auto tuned your filters) the filters track nigh on perfectly in equal temperament, with certain settings they may not be quite as well behaved across the full range of the keyboard when pinging. I started off with binaural mode off, just using the left output and Pan/LR Phase set to maximum. What I could hear is that there’s some inconsistency in the resonance amplitudes per filter. A few of my 12 filters have stronger resonance than the others. This tends to vary by base frequency as set by the filter frequency slider. Fine tune things by re-adjusting the resonance slider, ENV1 Decay Hold time, filter drive has less of an effect than I imagined it would but is always worth checking.
You can try playing the filters polyphonically due to the fact they’re tracking the keyboard. Depending on how you’ve set everything it may be more or less consistent. We need to bear in mind on the Super 6 that there are only 6 mod paths for some mod routings (I forget them all but keytracking is one) even though we have 12 filters. You may hear some amplitude differences between the filters as they round robin. At this point I decided to go into binaural mode (re-insert the left jack and monitor in stereo again). Due to the binaural mode phasing nature you will hear your notes panning around somewhat randomly.
Some more wiggy fun can begin now (:
Obviously we can no longer use the DDS2 slider in the filter section to modulate the self-oscillating filters at audio rate but of course, we have LFO1 in HF TRK mode (: Push LFO1 rate up to adjust the filter FM frequency. You can have it static or I tried routing ENV1 to LFO1 filter depth in the mod matrix. Adjusting the Decay, Sustain and Release of ENV1 brings in excessive pitch modulation of our pings but the Attack parameter kinda can give a bit more of a shLAP sound to the pings.
By now the sound design is up to you and where you want to go. I started by routing the Bender to filter frequency in the mod matrix and recording that into sequences but there’s any number of things to try. To fine tune key tracking you can (on S6 Desktop at least) try Note to Filter frequency in the Mod matrix.
So that’s been my 12 hours in the land of Ping. Hope it’s been useful for someone
You may have approached it differently, let me know how you did it if so. It’s a different technique to just playing the filters in sustained self oscillation where their decay is more consistent i.e. not based on the filter coming to rest from excitation. I love the latter technique it’s perhaps more consistent and many of the audio rate modulation tricks still apply but from what I understand, pinging filters allows for more organic note decays due to the inherent instability of analogue filters. The transients are quite different as well with the former having a thicker, more percussive beater sound vs the purer, hand drum like transients of the gated pings. Bongos and congas abound, Enjoy!
Btw I have to say it now I’m here: UDO = Best Performance Synth company of the 2020s for me, thanks so much guys for realising what makes synths great and bringing it to market, I met some of you guys at Superbooth ‘23 & ‘24 plus Machina Bristronica ‘24 and hope to be able to make it to Machina Bristronica ‘25 on the Sunday. I’ve got so much to talk about since finally getting a Super 6 !!