DDS2 Phasing Issues

UDO Audio Gear Super 6
1

Hi all. I recently acquired Super 6 and I am pretty much blown away by the core sound.

TLDR: DDS2 is phasing on itself in Binaural. Here is a quick video: https://www.youtube.com/shorts/WNuSCfYmgTs

Writeup: I had some time to dig around the voice modes and I found what seems to be a bug in DDS2 while in Binaural (or maybe that is just how the things go with it, I could not find any inputs on this matter though).

Basically, I wanted to create a PWM bass. So I put mixer all the way to the right, PWM wave option on the DDS2 and I linked the LFO to the PWM in the DDS modulator. Binaural, since the Solo voice mode is hardwired to it. Basic PWM bass is born.

All seemed good, but I noticed there is odd phasing going on every couple of key strokes. I tried multiple things in the patch to fix it, but nothing really worked. I suspected the problem is in the oscillator.

Initialised again, 100% DDS2 and yeah, it is there right away, with any wave I tried. DDS1 has no such problem.

I also tried it with just the Left output, summed to mono and the problem is still there. Only way to not have this problem it seems is to disable the Binaural, but that means no Solo mode.

This is pretty annoying, as I am unable to hold a stable tone, also rendering the whole PWM (and pretty much any sound made with just the DDS2 unusable).

Is this just the way of this synth or can this be bypassed? Does it happen to you too?

Thanks!

2

Could it be that done drift is dialled in by default? It is present in the init patch.

3

I suspected the drift control too, but no luck there.

What I eventually noticed was that in the Ableton’s stereo input I used for the S6, both L and R were centered in the pan control, instead of hard-panned (from when I had tried using non-Binaural mode in mono earlier). This meant that in the video I attached, I was basically feeding the imager a double-mono signal, which caused the issue. In default true-stereo mode, everything seems fine with DDS2.

However, summing DDS2 to mono (pretty important for bass IMO) still brings the problem back. It doesn’t matter whether I sum it in-the-box or physically take only the L output from the synth—the phasing is still there. I tried new cables and even tapped the signal from the headphone out. No change.

Then I had an idea: I created separate mono inputs in Ableton for the synth’s L and R channels instead of using a stereo input. Using either channel on its own as a mono source works, and both L and R sound identical when isolated. No phasing.

Here’s where it gets weird:
– If I use only the L channel in Ableton, then physically unplug the R output on the synth (the standard mono-sum method per the manual), the phasing returns.
– If I use the R channel in Ableton and unplug the L output, nothing changes.

I’m not entirely sure what all of this means or whether my workaround is ideal, but I can record DDS2 in mono now, which was the goal.

Summary:
If you want to use your S6 in Solo mode with DDS2 and sum it to mono for lead or bass, do NOT physically remove the R channel. Summing Binaural mode to mono inside the synth introduces phasing—but only with DDS2, for some reason. Also, do not sum the stereo signal anywhere else outside the synth, it is pretty much impossible. Instead, split L and R into separate mono inputs in your mixer/DAW and use only one channel as your mono source.

Hope this helps somebody somewhere at some point!

4

In my experience, the easiest way to get a true mono sound is to use the synth in binaural mode, and mute the right channel of the S6 on my mixer or in the computer. Always leave both jacks plugged into the synth.

I suppose the only disadvantage, versus the method outlined in the user manual, is that you only have 6 voices, but for my tastes and uses that has never been an issue.

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