# QU 16 - ST3 input - how do I mono this

**URL:** <https://forums.allen-heath.com/t/qu-16-st3-input-how-do-i-mono-this/13217>\
**Category:** Qu General Discussions\
**Created:** [9 May 2023 14:33 UTC](https://forums.allen-heath.com/t/qu-16-st3-input-how-do-i-mono-this/13217 "2023-05-09T14:33:41Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![olakunle-odebode](https://avatars.discourse-cdn.com/v4/letter/o/9e8a1a/32.png) [@olakunle-odebode](https://forums.allen-heath.com/u/olakunle-odebode)\
**Post date:** [9 May 2023 14:33 UTC](https://forums.allen-heath.com/t/qu-16-st3-input-how-do-i-mono-this/13217/1 "2023-05-09T14:33:41Z")

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I manage a Qu 16 digital mixer. Our mixing strategy is mono, so no panning on any mono inputs. Therefore same signal goes to main outputs Left and Right.

When I send a stereo input into the 1/8th inch ST3 input, such as the output from a mobile phone, or laptop, I’d like this to be mono, and I have not figure out a way to achieve this. Maybe it exists and I have not read enough of the manual.

The approach I had in mind which I know will work, would be to convert this to two mono inputs, via a suitable cable, pair these two mono inputs - i.e link them together, and adjust the panning, to make it mono. this I know will work, but that’s using up two channels.

It would really be nice if I could use ST3 which is the perfect input for my needs, and just mono it.

Thanks in advance. Highly appreciated.

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**Author:** ![lee7uk](https://sea2.discourse-cdn.com/flex002/user_avatar/forums.allen-heath.com/lee7uk/32/2014_2.png) [@lee7uk](https://forums.allen-heath.com/u/lee7uk)\
**Post date:** [10 May 2023 16:49 UTC](https://forums.allen-heath.com/t/qu-16-st3-input-how-do-i-mono-this/13217/2 "2023-05-10T16:49:28Z")

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There is no real provision to do the above from within the desk, I don’t think so anyway.

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**Author:** ![garyh](https://avatars.discourse-cdn.com/v4/letter/g/958977/32.png) [@garyh](https://forums.allen-heath.com/u/garyh)\
**Post date:** [10 May 2023 23:49 UTC](https://forums.allen-heath.com/t/qu-16-st3-input-how-do-i-mono-this/13217/3 "2023-05-10T23:49:45Z")

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With a stage box you can send L+R to an output. Without a stage box you would need to make or buy a stereo to mono outboard device.

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**Author:** ![mikec](https://avatars.discourse-cdn.com/v4/letter/m/977dab/32.png) [@mikec](https://forums.allen-heath.com/u/mikec)\
**Post date:** [11 May 2023 00:51 UTC](https://forums.allen-heath.com/t/qu-16-st3-input-how-do-i-mono-this/13217/4 "2023-05-11T00:51:13Z")

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If you have a system processor DSP look at doing the mono summing in the DSP.  
If your not already using the ALT OUT you can select L+R mono summing as an ALT OUT option.  
Or…look up “Rane why not to Y” they a the schematic for a passive summing circuit using resistors, it works  
well I’ve made a few, you can fit the parts into an XLR connector.

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**Author:** ![olakunle-odebode](https://avatars.discourse-cdn.com/v4/letter/o/9e8a1a/32.png) [@olakunle-odebode](https://forums.allen-heath.com/u/olakunle-odebode)\
**Post date:** [22 May 2023 08:59 UTC](https://forums.allen-heath.com/t/qu-16-st3-input-how-do-i-mono-this/13217/5 "2023-05-22T08:59:30Z")

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Thanks everyone, your responses are highly appreciated.