stereo image clone thingy...?

[Jim_L]

Well, after looking at the vast amounts of pics here (holy cr@p!), it got me to thinking...
I don't know what to call the effect i've heard before on the radio on some commercial announcements but it would be a doubling effect of some kind.
I'd love to get it for my guitar as I'm always thinking about stereo placement of instruments & vox.
Basically i'd like to get a single source (guitar and/or vox) and have it come out on the far left & right of the stereo field at the same time.
It's not a delay or chorus effect and recording a single audio source (like guitar or vox) onto 2 channels and hard panning is not it either.
So I don't know what it's called but if there's a chance of building one within reason.... i'm in.
Thanks for reading.
-Jim

[Suicufnoc]

Unless I'm misunderstand what you mean, the "best" way to do it is to double mic the amp, hard pan, and put a small delay on one channel (a few milliseconds).

[Earthscum]

Are you thinking something like a stereo ping-pong?

[Mark Hammer]

If there are phase differences between left and right versions of a signal, it can appear to have a stereo image.
If there are delay differences between left and right, it can appear to have a stereo image.
If there are spectral content differences between left and right it can appear to have a stereo image.

Back in the days when I'd buy vinyl albums that said "Electronically reprocessed for stereo" on the cover, Philips used to make a chip that was a "stereo synthesizer".  Basically, it was a fixed phase shifter that produced complementary notches and peaks, yielding two output copies of the mono input signal.  One had peaks where the other had notches, and vice versa.  No time difference between the two outputs; they just sounded different from each other, and that was enough to trick us.

These days, more sophisticated trickeryis used.  My guess is there is no audibly discrete delays, but some sort of very short delay difference is being used.  I know the old A/DA Stereo Tapped Delay used to include stereo positioning of mono input signals as one of its many possible uses.

[Jim_L]

i remembered after i hit the 'send' button that I had come across an expensive 'studio quality' rack mount device online way back when (and I searched to no avail, forgetting what the brand was) that had an audio sample online.
I thought it was a Fractal Audio unit and searched there but it didn't have the sample.
Somehow the unit took the mono audio signal (again, whatever you put in it, guitar, vox, etc.) and put it hard left and right. No delay or reverb, nothing in the middle.
Identical in execution but far apart in the stereo field.

[artifus]

http://www.soundonsound.com/sos/jan07/articles/pcmusician_0107.htm#2
http://www.soundonsound.com/sos/nov10/articles/stereoprocessing.htm
http://www.soundonsound.com/sos/oct00/articles/stereomix.htm

[Jim_L]

I found it:
http://www.dawsons.co.uk/tc-helicon-voice-pro-rack
check out the audio samples near the bottom of the page, samples #1 & #4
it's a doubling effect.

btw, thanks for the articles Artifus, i don't use a computer but their still interesting!

[frequencycentral]

ADT. You can adapt a Little Angel to do it.

[Earthscum]

I am soooo confused... what you linked does exactly nothing of what you have described... actually, it seems to do everything you said the effect you were searching for did not to have. Mis-link? or am I completely missing something here...

[Rodgre]

It's definitely a process of delay and pitch shifting. Not unlike chorus. Not unlike mild pitch shifting. Not unlike short-delayed doubling.

I know what you're saying. It's a dramatic effect when you suddenly hear it happen in the context of a mono voiceover. Still, it's not too different from what you get with any time/pitch based doubling effect. Definitely not like the old-school 70's "stereo synthesizer" effect you get from an old Orban unit.

If you want that sound for a guitar, I would look into the Boss Dimension circuit, which uses 2 delay lines, modulated out of phase with each other, so in stereo, you don't hear the cyclical sweep of a standard chorus, as both sides are balancing each other out, pitch-wise.

Another thing to keep in mind, as far as live guitar sound is concerned, contrast is key. If you run your rig with this effect on it all the time, it might sound great to you, because you know it's happening, but after a while, it just becomes wallpaper. It is most effective when you can switch the effect in and out for appropriate parts. To me, that's the most impressive way to use stereo spreading effects. Every time you switch it on or off, the listener notices the change and it's more of a "wow!" moment.

I run a stereo guitar rig when I play live and I use varying degrees of stereo, which can be effective in either a large venue with a stereo PA, or a small venue where your stage volume is heard by the audience. Just running the same signal into two different kinds of amps is one form of stereo. Then I have a stereo delay with modulation on one side of it, which makes for a nice subtle spread between the amps. Then I have a TC chorus JUST on one amp when I want the extreme spread. I developed this after using a Roland JC-120H in stereo for most of the late-80s/early-90s, with the chorus always on. It got really dramatic when I shut it off, then put it back on.

Roger

[Processaurus]

http://www.soundonsound.com/sos/jan07/articles/pcmusician_0107.htm#2
http://www.soundonsound.com/sos/nov10/articles/stereoprocessing.htm
http://www.soundonsound.com/sos/oct00/articles/stereomix.htm

About midway through the 2nd link (Faking Stereo With M/S, and Faking Stereo with Reverb and Delay) is some very good reading for prospective pedal designers interested in stereo-fying their effects.

Back in the days when I'd buy vinyl albums that said "Electronically reprocessed for stereo" on the cover, Philips used to make a chip that was a "stereo synthesizer".  Basically, it was a fixed phase shifter that produced complementary notches and peaks, yielding two output copies of the mono input signal.  One had peaks where the other had notches, and vice versa.  No time difference between the two outputs; they just sounded different from each other, and that was enough to trick us.

That sounds like a form of faked Mid/Side, where you have your dry guitar in both channels (the Mid) and then the effect (the Side) added to the dry guitar in phase on on channel, and out of phase on the other.  In this case the synthesized "Side" is a phase shifted signal.  You see it as well with stereo output chorus and flanger pedals.

[tca]

You could try this: http://www.ethanwiner.com/St-Synth.html

or look at some patents to get some ideas: http://www.google.com/patents/US4239939

This last stereo synthesizer is quite simple. Please tell us something about if you build such a device.

Cheers.

[Jim_L]

Sorry for such a late reply.
As for the linked page effect I posted, I should have said "This is what I found on my initial search that was very close to what I heard."
It has a rough aproximation of the 'stereo sound', if the effects could be turned off.
It's not a ping pong or stereo delay effect but some kind of doubling (i hate using that word as it's not quite correct) where the signal is panned hard R & L with no delay or phasing.
For example, you can come close recording yourself talking the same thing on 2 tracks once at a time but as your 2nd 'take' isn't exactly as the first, it will be more of a chorus effect & won't be the same.
Thats about as close to an explanation as I can come up with.

Maybe it can be done on a computer with the same audio source (as a reference example), I don't know, I don't use computers.

[Gurner]

Basically, it was a fixed phase shifter that produced complementary notches and peaks, yielding two output copies of the mono input signal.  One had peaks where the other had notches, and vice versa.  No time difference between the two outputs; they just sounded different from each other, and that was enough to trick us.

A phase shifted signal is a signal that leads or lags the original, ...therefore time differences are definitely in there, albeit small ones and not the same time shift across all frequencies.

.
For example, you can come close recording yourself talking the same thing on 2 tracks once at a time but as your 2nd 'take' isn't exactly as the first, it will be more of a chorus effect & won't be the same.
Thats about as close to an explanation as I can come up with.

Maybe it can be done on a computer with the same audio source (as a reference example), I don't know, I don't use computers.

What you describe is what a chorus pedal actually tries to emulate.