phantom images in stereo

    Mar 04 2006 | 9:49 am
    Does anybody have any experience with producing phantom images in stereo? I'm looking for that one sound that really jumps out of the speaker, and suddenly seems to be behind the listener (okay, behind and beside... not directly behind). There's an Aphex Twin track that does it, and it just produces such an amazing sensation... knowing that there are no speakers back there, but the sound's there anyway. I'd love to figure out how to duplicate that effect. I've been playing around with basic delaying and filtering, but though I can get a sort of enhanced stereo position, I can't seem to get that real mind-blowing "he's behind you" feel.
    Any tips?

    • Mar 04 2006 | 11:24 am
      ...update. I managed to get a pretty good sense of it by taking my input (mono in this case), sending the clean signal to the left channel, and sending the right to delay~ (around 60.), fffb~ (mid/high roll-off), comb~ (21., 0.35, 0.35, 0.54), and then just adjusting the right channel level to taste! Not bad.
      I juiced it up a little, as well, by adding a stereo vst~ reverb, using only the left input, but both outputs (the non-vst~ed, but delayed, signal is still going in clean to the right channel).
      Still, if anybody has any killer techniques for heightening this sensation, I'd appreciate any tips.
    • Mar 04 2006 | 1:33 pm
      you produce that effect by adding a phasereversed L signal of up to 30% to the R channel.
      if you do that, also experiment with dynamic control, or try to apply this effect only to the mids and highs, or only to the louder parts of the signal.
    • Mar 04 2006 | 6:19 pm
      Thanks Roman,
      I've been playing around with that and it does seem to do a better job than just delaying -- maybe a combination of the two would be even more dramatic(??). I guess pushing it farther would be down to frequency content and room acoustics, so I'll mess around with different input sounds until I find one that really jumps. (I'd imagine it also has a lot to do with dynamic control, as you mentioned, since it's the perception of moving which provides the context for judging how "far back" the sound is at any given moment... at least, in part.)
      I also checked out the link in your signature -- that's really handy. I was wondering if there was a complete list of AU/VST anywhere...
    • Mar 05 2006 | 2:32 am
    • Mar 05 2006 | 10:11 am
      Yeah, I'm really just looking for the occasional "error" in the imagining... something to jump out of the mix, here and there, as an effect. I'm not necessarily trying to produce a stable image, in a certain position. The overall stereo image of the mix would provide the context for these "popping out" sounds. I certainly understand what you're saying about listening environment, and so on. I actually never noticed these effects in the Aphex Twin track I was talking about, until I got new speakers. I moved from decent home-stereo speakers, to entry-level professional speakers (Blue Sky Mediadesk 2.1 -- highly recommended, for the dough!), and suddenly the imaging opened up, and everything I was hearing became so much more detailed.
      I was thinking of delays because, as I understand it, timing errors influence the perception of direction (so long as the delays remain within the 50 ms window within which the percept "fuses"). Aren't these timing errors resulting in similar phase issues? I'd wondered, also, whether raw electronic sounds -- simpler waveforms, without room influences already present (like samples) -- would give a more pronouced effect, so thanks for the heads-up on that.
      Anyway, the phase thing will do for my purposes. I'm building a performance instrument that will respond to drum patterns, in a sort of interactive composition program. I'd just like to incorporate this "image-messing-up" effect as another possibility.
      Thanks for the help.
    • Mar 08 2006 | 7:44 am
      jbmaxwell wrote: > There's an Aphex Twin track that does it, and it just produces such > an amazing sensation... knowing that there are no speakers back > there, but the sound's there anyway.
      Which track is it? Maybe when I hear it...
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