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    Experimetal thundertorm recording


    As an experiment I made an attempt to record a thunderstorm with mics on two sides of a building.
    The goal was to create a nice stereo effect.

    http://freesound.org/people/klankbeeld/sounds/240307/

    Gear chain
    * Rode NT4 XY in Rode Blimp > Sound Devices 302 >Tascam dr-100 Mk2.
    * And Primo EM 172 In Rode Blimp > Sony PCM D50 recorder

    In (my) theory it is/was not possible to get a nice result because;
    1 the great distance (10m) between the mics
    2 the building as barrier between the two signals (I want to use this)
    3 the out-of-sinc problem of the two different recorders

    Steps in Audacity to create the result
    Step 1 - Change Left/Right of the EM172's
    Step 2 - Synchronisation of the two signals.
    Step 3 - Rode NT4 (XY90) signals split to double mono
    Step 4 - Invert one channel of EM172's to create a special MS setting (to create accent on left and right channel.
    Step 5 - Than these signals tune and combine.

    This (NEW?) recording technique I call the KMS setting. K stands for Klankbeeld, hahaha an MS for normal MS setting.

    He man, It worked..... I could not believe my ears...

    PLEASE LEAVE YOUR COMMENT

    To hear, you first have to listen
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    You could try to emulate smaller distances, but larger than human head.

    As for syncing - check if your devices are well calibrated (different devices, at 44.1kHz may have few Hz diffs; at 1kHz signal up to 1%). Just record sine tone with these two, and mix the results on the computer. If there is a slow or fast beating - devices are shifted.

    You could try to manipulate delay between tracks (even binaural recordings use delay compensation between ears) to get wider and more full space.

    Try to play with directionality of mics (like 90 degrees, 120 degrees, 180 degrees - such sort of stuff).

    Call this JKC correction routine wink

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    thanks for the information @ayamahambho

    To hear, you first have to listen
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    I liked the recording, but found the volume a bit low. I was listening on crap headphones, so that could have been it.
    There is definetely stereo separation there, but I will create an amped version of the sound and re-listen.

    An interesting use of this would be if you can access large closed spaces (a church, for example would be ideal) and position mics on opposite sides of the room then record.

    As for aligning the two recordings, why not use a cue sound?
    This could be somethign like the beep from a digital clock. This sound should be emitted at the same distance from the 2 mics and be clearly picked up by both of them.
    This sound can be at the start or at the end of the recording. If you then alingn the 2 beeps on both tracks you will have aligned them to the same time reference.

    Not sure if the clock on 2 devices can really be out by as much as 1%. I would imagint that would be noticeable:
    - Notes would sound slightly out of tune (440Hz tone would become 435.6Hz or 444.4Hz
    - worse, a 120bpm loop would become 118.8 or 121.2bpm.

    Happy experimenting !

    I want to believe.
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    Hi Alienxxx,

    Thanks for all the tips and tricks.

    I will try one day to do the recording in a large room. great suggestion.

    And the cue sound was a bit hard because the mics were outdoors. But You are right its the bet thing to do. Next time I start recording indoors with the mics close and cue. than place the mics outdoors. the same at the end. Great tip Alienxxx.

    and, when the recorders go out of sing during a long recording..... we'll see.
    It was just fun to do..
    thanks Alienxxx

    To hear, you first have to listen
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    2071 sounds
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    Easy to test:
    bring the two records next to each other before stopping the recording and generate another cue sound.
    If you align the cue sound at the start of the recording and you find that the cue sound at the end of the recording is aligned - then the recorder clocks both run at the same speed. smile

    I want to believe.
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    Great tip. Thanks

    To hear, you first have to listen
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    I found nothing wrong with the original recording!

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    Thanks lonemonk

    To hear, you first have to listen

    9 posts