Phase issues in non-binaural mode (not summing to mono cleanly)

When using non-binaural mode it always sounds hollow / phased in a weird way when summed to mono (thought it might be the sounds I was making but it happens with the raw oscillators). Initially thought it was my unit but tried another one out at a store and it had the same issue.

This is the weird thing - when I try using it in mono mode (only plugging into one output) the phasing issue happens with the left output, not the right.

Has anyone else noticed this?

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Weird question, but was this a sound using just DDS1, DDS2, or both?

I ask because on my unit, DDS2 is unbalanced, comes out left or right of center when in binaural mode. I let support know, they replicated the issue, and said it was added to the bug list for future firmware. So maybe, if it’s only DDS2, that’s the issue you’re hearing.

This is just a guess, but: If using only the Left output auto-switches to Mono Sum (combing Left and Right signals to Left out), as stated by UDO, then you will get phasing because the outputs are at slightly different levels and phases I think, even in non-binaural mode. You may be able to mitigate this by making sure the new “slop” control is at minimum. If you only use the Right output, it doesn’t Sum to Mono, so you are only hearing the Right output, therefore, no weird phasing.

Isn’t non-binaural just simple voice panning though? Like each of the 12 voices is just a mono source placed randomly in the stereo field, so in theory it should sum to mono perfectly, especially if we’re talking just one voice running one oscillator and nothing else.

Binaural is obviously going to have phasing to some degree but in most of the patches I’ve made this hasn’t been an issue, at least not towards the general tone / EQ balance of the patch. Summing to mono in non-binaural seems to completely scoop the mids.

Also tried with DRIFT feature at minimum setting and unfortunately doesn’t do anything in regards to this.

Recorded a little comparison if you wanna check it out, let me know if you can hear the difference:

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Happens with both DDS 1 and DDS 2.

Even before the new randomise/drift control, I’m pretty sure George has said that there were already subtle differences in the L & R, introduced deliberately at the digital stage, and by the slight difference in tolerances between the analogue components. Which may be the cause of the phasing that is clearly audible in your link.

Subtle differences shouldn’t be that destructive though - really hoping this is a bug / something that they can turn on or off if it was a deliberate choice. I’m definitely pedantic but it makes non-binaural unusable for me :frowning:

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Hey so I have busted out Voxengo Correlometer and confirmed that with Binaural mode switched off there is indeed comb filtering for both Poly Modes.

As with the Binaural mode it appears that while playing notes in the lower registers its mostly 100% phase correlated (basically mono) under 300hz.

I tested the left / right channel only suggestion and confirmed that you can use the right channel but there are subtle changes in volume and timbre every keypress which I personally do not mind. Left channel sums and exhibits comb filtering. With binaural engaged there is no comb filtering.

I personally don’t mind as I have barely made it out of binaural mode and 6 voices has been plenty, but I would love to see the pan implementation / comb filtering addressed in an update down the line somewhere and the pan-spread assigned to the LR Phase slider going from centre-panned all the way to hard R/L when binaural mode is disengaged.

Big ups to UDO this synth rocks! Take care & greetings from Aus :slight_smile:

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Not really!
I described it there:

Would be nice if we could get a normal 12 voice mono (as in not-stereo) mode.

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It does sound a bit strange. I mainly use my super6 with headphones, and in a weird way, it almost sounds wider when I turn off binaural, and more centered when I have it on. Yeah, looking forward to this getting fixed

So if I have binaural mode turned off with stereo output and I quickly press a note multiple times, I notice that it dances around from left to right. I think this kind of behavior is fine in some situations, but there are definitely times where I’d want to have things more centered as well.

Is this the same behavior you guys are experiencing?

As far as i understood, this is not a bug, it’s a feature!
The voices in non-binaural mode are distributed to the stereo channels in a way, that with headphones they sound some kind of realistically from one side (or the other) outside your head… and this is definitely not an accident.
In binaural mode, when two voices play in parallel, this effect get’s a little lost, but then you have other stereo effects, that are not less interesting.

If you use the Super6 as a solo instrument, than this is some kind of impressingly nice.
In other setups this might be disturbing.
So it should be optional.
And i got the response from support, that making this optional is on the feature whish list.

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Good to know! In all honesty, I plan to use the synth in binaural mode 95% of the time, so this isn’t a massive issue… But it’s also my only polysynth, so having the option to turn this off would definitely be a big plus.

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Is anyone else able to confirm “As with the Binaural mode it appears that while playing notes in the lower registers its mostly 100% phase correlated (basically mono) under 300hz.”??

This would be pretty good to know in the manual, for mixing purposes. I’m also curious what happens to the bass frequencies in the super modes.