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mr.extrem
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Q: True Stereo IR's from a reverb unit..

Next week i have the chance to borrow the new Lexicon pcm96 and want to make some IR's from it. But there is something that confuses me a little bit...

For true Stereo IR's, i have to feed the Unit with a L and R Input Signal. But there is only one Output Channel available in the Sweep Generator.

And is there no other way to make a true stereo ir, than record it in 2 times? Because you don't have 4 diffrent outs from the Reverb unit where you can catch the L and R outputs signals from the two diffrent inputs L and R.
I hope you understand what i mean..

best regards Alex..

G5 dual 2.5 GHz, Soundcard: RME Multiface

Posted on May 29, 2009 12:12 PM

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mr.extrem

Q: True Stereo IR's from a reverb unit..

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  • by John Buehler,

    John Buehler John Buehler May 30, 2009 7:05 AM in response to mr.extrem
    Level 2 (385 points)
    May 30, 2009 7:05 AM in response to mr.extrem
    You are right, it takes two passes, a stereo recording of the sweep into the left input and out of the 2 outputs, and then again for the right. It is essentially a 4-track recording. This is the correct way to do it.

  • by John Buehler,

    John Buehler John Buehler May 30, 2009 7:52 AM in response to mr.extrem
    Level 2 (385 points)
    May 30, 2009 7:52 AM in response to mr.extrem
    By the way, I've done quite a bit of Lexicon units, and it is very important that you turn off the ubiquitous chorusing that is in most Lex verbs. Chorus ruins the sweep. Best to turn it off, and then use the Modulation delay in Logic to recreate the chorusing.

  • by mr.extrem,

    mr.extrem mr.extrem May 31, 2009 2:33 PM in response to John Buehler
    Level 1 (0 points)
    May 31, 2009 2:33 PM in response to John Buehler
    Hi John thanks for the answer...

    Actually i thought the choruses in the lexicons are nested deep in the algorithms and thats not possible to turn off the chorus ore other modulation-effekts.

    And because of this choruses nested most in the algoritm it is very hard to imitate this with patching a chorus just post ore pre to the space designer. I think it's quite impossible this way.... I tried this out, and what came out sounded just ****.

    But when you know more about this, please let me know..

    Do you patch the chorus post ore pre to the reverb?

  • by Pancenter,

    Pancenter Pancenter May 31, 2009 3:00 PM in response to John Buehler
    Level 6 (9,923 points)
    Audio
    May 31, 2009 3:00 PM in response to John Buehler
    John Buehler wrote:
    You are right, it takes two passes, a stereo recording of the sweep into the left input and out of the 2 outputs, and then again for the right. It is essentially a 4-track recording. This is the correct way to do it.


    I would also take an impulse response of Mono in Stereo out as the Lexicon internal stereo simulation can often be quite dramatic when used with voice, brass or woodwinds.

    Oops. nevermind, of course you will have that, and more.


    pancenter-

    Message was edited by: Pancenter

  • by John Buehler,

    John Buehler John Buehler May 31, 2009 3:01 PM in response to mr.extrem
    Level 2 (385 points)
    May 31, 2009 3:01 PM in response to mr.extrem
    I've never had trouble turning off the chorus on any Lexicon, but I haven't done a 96 yet. I can't imagine it's difficult. The chorus is always post reverb when I do it, meaning the chorus is applied to the output of Space Designer, not the input. The chorus is very subtle, like 1-2%, and it gives it a little more depth and variation to the reverb, and to my ear it makes the reverb sound much more like a Lexicon. But you can easily over-do it, and there a lots of chorus effects that sound like garbage to me. The chorus in a Lex verb is very pure and clean. I have also simulated the early-reflection type multi-tap delay signal that exists so prevalently in the input of the PCM-70, 80 and 90, and with enough effort you can get quite close. It's just a lot of work.

  • by mr.extrem,

    mr.extrem mr.extrem Jun 12, 2009 11:50 AM in response to mr.extrem
    Level 1 (0 points)
    Jun 12, 2009 11:50 AM in response to mr.extrem
    So i made some ir's of the pcm96...
    A few are not bad, does mean it sounds almost as the original algorithm. But the are many who sounds very worse. For example the "Random Hall" algorithm, where much stereo modulation is happen, the IR of it sounds like mono. I don't know what's exctly the reason, but these ones are not possible to sample and use in your convolution reverb.

  • by John Buehler,

    John Buehler John Buehler Jun 12, 2009 12:06 PM in response to mr.extrem
    Level 2 (385 points)
    Jun 12, 2009 12:06 PM in response to mr.extrem
    It seems likely that a reverb like random hall could not be done using the true stereo method because it requires 2 passes, and because it's random, left and right aren't working together. I would try a regular stereo capture instead.

  • by mr.extrem,

    mr.extrem mr.extrem Jun 14, 2009 2:19 PM in response to John Buehler
    Level 1 (0 points)
    Jun 14, 2009 2:19 PM in response to John Buehler
    Also tried a monoIn- to stereo Out IR. But its even worse. I think there are modulations in this algorithm where not can be reproduced by convolution technik.
    That's maybe the reason why this Hardware peaces are still very popular in many studios

    And its very living. Each snare drum sounds diffrent...