Patchbay Half-normalled?

[billisa]

My synths are all designed so that when the right output is unplugged, a mono signal is sent via the left output...

So, if I want to permanently hook up the synth to a patchbay, but want to retain the ability to record a mono signal (or both L/R through the same channel), should I set the patchbay synth connections for the synth to Half-Normalled?

This way when only plugging into the Top-front Output (Left), the Bottom front (Right) signal will be routed to the Top-Front thus giving a mono signal (or combo L/R) from the synth and not just the left channel?

[Whale Bone]

That's a nice idea. But I would want to know if that's how the keyboard combines the two signals, i.e. are they simply combined, or are they 'mixed' to adjust the output level/impedance, or is the keyboard processing a mono signal differently for the sake of patches or effects?

[billisa]

Originally Posted by Whale Bone

That's a nice idea. But I would want to know if that's how the keyboard combines the two signals, i.e. are they simply combined, or are they 'mixed' to adjust the output level/impedance, or is the keyboard processing a mono signal differently for the sake of patches or effects?

Thanks for the help. Apart from the L(MONO) R design, I don't know how each of my synths work. BUT from what I can HEAR my approach seems to work, at least within the Patchbay part of the equation. It effectively sounds like a mono signal (like recording L/R on 2 separate tracks, but panning them both dead-center.

The schematic of the Half-Normalled setting seems to show my idea should work. BUT I am no engineer!

So I guess leaving the synth design out of it, assuming the original scenario, it seems like you're saying that (for better or worse) the Half-Normalled setting is combining the L/R into the Top output?

[Big Kenny]

Give each out (L mono , and R) its own slot on your bay. When you want the mono, plug in the L mono, want stereo? Plug 'em both..

[billisa]

Originally Posted by Big Kenny

Give each out (L mono , and R) its own slot on your bay. When you want the mono, plug in the L mono, want stereo? Plug 'em both..

OK, AND using the Half-Normalled setting on the PatchBay? This is what I've been doing...

Thanks.

[Whale Bone]

You are certainly combining the two signals from what you describe. My question is if the keyboard does anything special to combine them or does it just do it the way you're doing it. I doubt you're hurting anything. If you are able to record it effectively and get a full frequency response and have no odd cancelation effect, then I'd say you're probably fine.

If you A/B just the left of the keyboard and the left+right combined via your patch bay and detect no difference in level, response, etc., then I'd think you have no real worries - you're not dealing with power amp outputs that have high voltages that could be damaging.

If you found a schematic of the output section of your keyboard, you'd know for sure. It is generally bad practice to simply tie two outputs together without properly mixing them, so that's why I brought up the question of how the keyboard does it.

[MOFO Pro]

Originally Posted by Big Kenny

Give each out (L mono , and R) its own slot on your bay. When you want the mono, plug in the L mono, want stereo? Plug 'em both..

From his earlier description, I'm thinking that the two channels are summed into the left channel when only that connector is attached... as soon as he plugs the right channel in... he's got stereo L/R output from the synth... His mono output from the left channel will be just that, the left channel... To accomplish what he's attempting he'll have to patch from the right channel out to the left channel in without breaking the left channel. Bottom to top on adjacent channels...

[billisa]

Originally Posted by MOFO Pro

From his earlier description, I'm thinking that the two channels are summed into the left channel when only that connector is attached... as soon as he plugs the right channel in... he's got stereo L/R output from the synth...

Yes! This is what my hope is (unless this is bad in some way).

[Farview]

Most keyboards that I have taken apart do combine the left and right channels when nothing is plugged into the right output. This is done with a switching jack on the right output. When nothing is in the jack, it sends the right channel to the left output. When you plug into the right jack, the right channel is disconnected from the left jack.

I can't think of any way to duplicate this with a patchbay. The only thing I can think of is hook both outputs to separate patchbay channels. When you want mono, unplug the right output on the keyboard.

[billisa]

Originally Posted by Farview

Most keyboards that I have taken apart do combine the left and right channels when nothing is plugged into the right output. This is done with a switching jack on the right output. When nothing is in the jack, it sends the right channel to the left output. When you plug into the right jack, the right channel is disconnected from the left jack.

I can't think of any way to duplicate this with a patchbay. The only thing I can think of is hook both outputs to separate patchbay channels. When you want mono, unplug the right output on the keyboard.

Thanks! I think what you're describing as happening inside the keyboard is what would take place in a Half-Normalled Patchbay -- the Bottom output is routed to the Top. Thus, plugging a synth L/R into the Top/Bottom channels of a Half-Normalled PatchBay should behave like the synth it's wired to (I believe).