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kenhan

stereo / mono question

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Hello.

 

I output signal from Helix LT via XLR L & R to my interface. I'm curious what would happen if:

 

1. I output only from XLR Left. What happens to the stereo effects such as stereo delay? Do the L & R channels get combined?

 

2. Sometimes I output XLR L & R to my interface, and then go from 1/4 L out to my guitar amp. In this case is the 1/4 L only outputting what is going out of XLR L, or do XLR out and 1/4 out function separately so that XLR L & R output as separate stereo signal, and 1/4 outputs a combined signal?

 

Thanks.

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1. If you plug in only left output jack (XLR or 1/4) the signal is combined.

 

2. I believe i read an answer to this over a year ago, IIR, the outputs are treated separately. Stereo XLR while combined mono 1/4.

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The Helix's Main 1/4" and XLR Output format jacks are independent regarding either format's L/Mono jack summing to Mono only that format's output. The other format remains unaffected.

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1. If you plug in only left output jack (XLR or 1/4) the signal is combined.

 

2. I believe i read an answer to this over a year ago, IIR, the outputs are treated separately. Stereo XLR while combined mono 1/4.

This doesn't seem to work 100% for me. If I plug in only the left cable in the 1/4" direct into the mixer, stereo delay effects seem strangely warped. When I set the panning to Left 100%, then volume drops to about half of the original, but the mixdown doesn't cause the warped delay.

 

Note, I have the Helix Floor

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This doesn't seem to work 100% for me. If I plug in only the left cable in the 1/4" direct into the mixer, stereo delay effects seem strangely warped. When I set the panning to Left 100%, then volume drops to about half of the original, but the mixdown doesn't cause the warped delay.

 

Note, I have the Helix Floor

That's the "danger" of using a stereo setup then going mono. Stereo separates the timing and phasing etc depending on the effect your using, so when collapsed to mono, you experience phase issues.

 

Because you panned left, you loose 3db of the center sounds and also the right channel stereo effects, therefore; lose of volume and no phase issues.

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That's the "danger" of using a stereo setup then going mono. Stereo separates the timing and phasing etc depending on the effect your using, so when collapsed to mono, you experience phase issues.

 

Because you panned left, you loose 3db of the center sounds and also the right channel stereo effects, therefore; lose of volume and no phase issues.

Thanks, but what is a better way of collapsing to mono then?

 

Thing is, I record with my sounds in stereo on USB, but when I play live I play mono.

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Thanks, but what is a better way of collapsing to mono then?

 

Thing is, I record with my sounds in stereo on USB, but when I play live I play mono.

Build a second set list that is the same using all mono effects. Stereo reverbs seem to do ok in mono (at least the pre 2.5 ones.) I had to rebuild all mine for mono.

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Build a second set list that is the same using all mono effects. Stereo reverbs seem to do ok in mono (at least the pre 2.5 ones.) I had to rebuild all mine for mono.

Is there a quick way to change from stereo to mono without losing the assigned controls and snapshot settings?

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Is there a quick way to change from stereo to mono without losing the assigned controls and snapshot settings?

Not sure. I know you can change from cab to no cab on amps while preserving settings but stereo to mono I feel may not work.

 

Here is the amp way edited for effets....

 

It has to be done in the editor.

 

1. copy and past preset in New location.

 

2. Click on the effect you want to convert selecting it in the effects chain

 

3. Under effects chain find the same effect mono version and double click.

 

I haven't tried it for effects.

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Not sure. I know you can change from cab to no cab on amps while preserving settings but stereo to mono I feel may not work.

 

Here is the amp way edited for effets....

 

It has to be done in the editor.

 

1. copy and past preset in New location.

 

2. Click on the effect you want to convert selecting it in the effects chain

 

3. Under effects chain find the same effect mono version and double click.

 

I haven't tried it for effects.

Thanks I'll give it a shot!

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There's a post on here somewhere regarding this.  I don't know the exact method off the top of my head.

 

Export the preset you want to convert.  preset files are human readable text files (setlists and bundles are binary and unreadable).  There is a setting in there that sets each effect as stereo or mono.  Change it from stereo to mono (probably by going from 1 to 0?).  Save the file. Import the preset into a new location or setlist (maybe have a stereo setlist and a mono setlist?).  Should be all set.  A little complicated, but, easier than writing everything down if the way above doesn't work.  And with a little work, you could somewhat automate the process.

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Volume/Pan > Stereo Width (Stereo), Line 6 Original utility to collapse stereo paths

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On 3/15/2018 at 2:13 AM, rompelstompel said:

Thanks, but what is a better way of collapsing to mono then?

 

Thing is, I record with my sounds in stereo on USB, but when I play live I play mono.

Actually I read somewhere that Helix implements a make-up delay between stereo paths/channels to eliminate phasing issues. Not sure if it's extensively tested, but I'm using XLR left for live too, and no issues so far.

However, for stereo delays, you are intentionally adding "phase difference" between L&R. Usually, the L&R signals are separated far enough to avoid serious phase cancellation, and results in a somewhat pleasant chorusing effect when summed to mono. If that's not what you want, try messing with the delay parameters, particularly turning off pre-delay and reducing mod depth.

If that still doesn't work, you might have to make duplicate presets with mono delays. From experience, the other effects seem to sum to mono perfectly fine, so that's a bit better than reworking the entire preset to mono!

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2 hours ago, Meiannatee said:

Actually I read somewhere that Helix implements a make-up delay between stereo paths/channels to eliminate phasing issues. Not sure if it's extensively tested, but I'm using XLR left for live too, and no issues so far.

However, for stereo delays, you are intentionally adding "phase difference" between L&R. Usually, the L&R signals are separated far enough to avoid serious phase cancellation, and results in a somewhat pleasant chorusing effect when summed to mono. If that's not what you want, try messing with the delay parameters, particularly turning off pre-delay and reducing mod depth.

If that still doesn't work, you might have to make duplicate presets with mono delays. From experience, the other effects seem to sum to mono perfectly fine, so that's a bit better than reworking the entire preset to mono!

Still, it seems strange to me that the output's mixdown is different from panning to left. I get the volume drop, but how can the phases be different there than if I pan to left?

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I've figured out the difference between panning left 100% and summing left+right. Panning something that is on the right channel 100% to the left effectively mutes it. I've tested with a dual delay, only the right one mixed in. Then added a pan 100% to the left. Nothing. 

That's why I didn't hear the artifacts when panning... 

Thanks for the tips on how to easily change to mono! I'll do the dual setlist thing for now. 

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On 3/18/2018 at 8:05 PM, rompelstompel said:

I've figured out the difference between panning left 100% and summing left+right. Panning something that is on the right channel 100% to the left effectively mutes it. I've tested with a dual delay, only the right one mixed in. Then added a pan 100% to the left. Nothing. 

That's why I didn't hear the artifacts when panning... 

Thanks for the tips on how to easily change to mono! I'll do the dual setlist thing for now. 

Yes. To clarify panning:

 

At 100% L pan: L volume 100%, R volume 0%

At middle: L volume 100%, R volume 100%

At 100% R pan: L volume 0%, R volume 100%

 

All values in between are interpolations of the points above.

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1 hour ago, Meiannatee said:

Yes. To clarify panning:

 

At 100% L pan: L volume 100%, R volume 0%

At middle: L volume 100%, R volume 100%

At 100% R pan: L volume 0%, R volume 100%

 

All values in between are interpolations of the points above.

Thanks for clarifying

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