Max piece construction techniques


    Apr 01 2006 | 6:01 pm
    This is by no means exhaustive, but these are some things that I have
    found useful over the years, and I am indebted those who showed me some
    of these. These are for pieces that are through-composed, so they
    definitely won't apply in all cases. I'll be curious to hear your
    comments, opinions, refutations, etc.
    Peter McCulloch
    Performance:
    The patch should be as simple to operate as possible. If you're only
    advancing through cues, they should be operable from the computer
    keyboard. Do not ask the computer operator to click through cue
    numbers as it is easy to miss, and it forces the operator to focus on
    the screen instead of the music. Spacebar is large and hard to miss
    for advancing cues. Also, if it will be someone other than you
    operating the computer part (and without much rehearsal) do not ask the
    operator to do things that are awkward. I ran a piece that asked the
    computer operator to follow pedalling indications with the spacebar
    while clicking through very small messageboxes containing cue numbers,
    which left me with no hands free to turn pages or ride the mixer.
    Instead of having separate tasks, make them smaller tasks. So instead
    of "pedalling" to record into a long delay loop, have two cues, one for
    starting, and one for stopping. It's much easier to time for the
    operator.
    In addition to performance, your cues system should have some rehearsal
    algorithms built-in. Not necessarily that you should be able to skip
    around at random (though that would be helpful creatively), but
    moreover that if the piece begins with a two-minute soundfile, when you
    skip ahead, you should either skip ahead in the soundfile, or simply
    mute it, rather than having to wait two minutes for it to finish.
    Could even be as simple as having a button that stops all soundfiles
    that are playing. A "Panic" setting also can be a good thing, as it
    allows you a safe way of muting everything, before you rewind, etc. I
    use a big message box with sends at the beginning of each main section
    that will get everything set appropriately.
    There's a strong chance that you'll get the same 20-30 minute long
    sound check that the guy with the tape piece will. It's not fair, but
    it seems to happen a lot, so plan for it by making your interface/setup
    as monkeyproof as possible. Starting the piece should be simple and
    fast, and you shouldn't have to remember to open patcher x and click on
    three things in a specific order. (that's what trigger is for...) Be
    able to do a full reset of your patch WITHOUT having to reload it: use
    the universal object in the top-level patcher to make loadbang and
    loadmess reload where necessary. Being able to skip around in the
    patch saves valuable rehearsal time and allows you to test the parts
    that may present the most issues. Try to find out in advance whether
    you're dealing with a digital or analog mixer, and, if possible, about
    the experience of the engineer. Inexperienced engineer + fancy
    unfamiliar digital board with complicated setup = bring a small analog
    mixer as backup; you may be thankful. I've seen this equation play out
    very badly before at a national conference where you would have
    expected better.
    Prepare for different performance spaces. That long reverb may sound
    great in a small room, but may just be too soupy in a large room.
    Having a trim on these type of processes (i.e. reverb time trimmed to
    -1 sec.) can help you quickly adapt without having to edit cues.
    Feedback delays are a particular candidate for this. You also don't
    have to do it multiplicatively; you could use a clip 0 0.95 before the
    feedback coeff. Vary the rightmost inlet to set the maximum amount of
    feedback gain, while preserving the lower values. You should have easy
    access to these trim values in case you have to compensate in the
    middle of the performance. Maintaining a list of values that have
    worked in the past can suggest patterns for usage. (these values seem
    to work in big spaces, these seem to work in small spaces)
    In performance, do not route the dry audio through your patch. (unless
    you have a strong musical reason for doing so) Use a prefader aux send
    into your computer. This way, the computer always sees a consistent
    level, and you can control the mix of the live instrument
    independently. Having a physical fader is always more useful in
    performance than having a virtual fader because you don't have to mouse
    for it. I've seen a lot of disasters happen by not following this
    rule.
    Have a way of easily testing your audio output. In my stereo patches,
    I have a test-sound player that loops a soundfile that plays different
    pitches in the right and left channels. (Make sure that the soundfile,
    etc. roughly conforms to the dynamics of your piece) This allows you to
    test output, set levels, and ensure that panning is correct all in one.
    If you're working with a performer, have a way of providing a tuning
    note. You could do it via the built-in synth, etc.; don't assume that
    there will be a piano, etc. where you're going to perform. (or that
    it will be in tune!)
    Have easy ways of recording the input and output of your patches. If
    you record the input, then you can use it later for testing purposes
    when the performer is not around, or when you're not in the performance
    space. Also, it makes it much easier to put together a recording.
    Having multiple recordings of the input makes it easier to stress test
    the patch. You might want to do some routines on the dac~ so that it
    shuts off recording before you shut off audio. (sel 0, trigger 0 0)
    Higher bit rates may be an especially good idea...
    If you're using qlist, try this trick: If you want to add a comment,
    type
    COMMENT This is adjusting the delay-time;
    then add a receive COMMENT with a gate and send it to print. Very
    useful for troubleshooting. I use an additional one called CUEACTION
    (or something like that) to describe what goes on in that cue. It
    helps in performance, because I can see what's supposed to be
    happening, so I know if part of a cue isn't firing correctly.
    Programming:
    Controlling the inputs and outputs of a process is almost as important
    as the process itself, so envelopes, or even just the ability to easily
    bypass the process can be very useful. Processes that are always on
    chew up sonic space and lead to a reduction in information. (things
    that always move together become perceptually grouped under Gestalt
    theory) I also use spatialization to move processes from foreground to
    background.
    Gain control is one of the most important things in ensuring consistent
    performances. Making sure that signal-processing parts of the patch
    see the same approximate signal levels each time you run the patch
    helps you to assure a good blend with synthetic components and
    soundfiles. Adding a volume meter with a target level in the main
    patch is a good step towards this. (specify the note(s) that this
    should target; i.e. the fortississimo high C instead of the
    mezzoforte F#) I'm working on developing some calibration routines
    that will try to do this automatically. Use peak in combination with
    meter~ to keep track of the loudest incoming (and outgoing) amplitude
    so that you can trim accordingly. Generally speaking, I've found it's
    more effective to have performers play the loudest part of the piece
    while you're setting levels than to ask them to play their loudest
    note, because they'll tend to underestimate.
    Modules should have multiple levels of gain control. You should be
    able to access it in an on/off fashion, but also variable, and having
    an additional trim component to this all is extraordinarily helpful. I
    use a toggle, floatbox, bondo, * 1. combo for this. There should be
    mute/unmute subroutines so that the module cleanly enters/exits the
    mute state without clicks. I use matrix~ 1 1 0. for this. (sending it
    0 0 $1 100, etc.) It's musically advantageous to be able to turn
    on/off the input without doing the same for the output.
    If you have a very prominent feedback delay part of the patch, have a
    way of clearing the input, or at least quickly reducing the amount of
    feedback should an undesirable sound get stuck. It's very important
    to use an envelope to control the input, needless to say.
    Otherwise that one click turns into
    click.......click.....click.....click.....click.....click... . And
    high-frequency feedback...eeeee.... A clip~ on the output, or
    somewhere in the chain, can be a very practical thing.
    Matrix mixers can provide a lot of sonic variety. Having access to
    multiple delay units as part of the chain can make the other processes
    more interesting. Also, WHERE you listen in the process can be very
    important. Think also about the way that mixers work, what with using
    aux sends, etc. on processes. You might not need a full-blown matrix~;
    I've seen very elegant solutions done with poly~ and changing the
    targets of send~ and receive~ objects.
    Spatialization can be very effective as a means of density control. If
    you use two reverbs instead of one, you can create nice effects like
    sounds moving off into the distance on the left, right, etc. With a
    little bit of lowpass filtering, and adjusting the wet/dry ratios on
    the signal, you can build a pretty decent spatializer, which will add a
    lot of depth to the sound. (though I like multi-channel, it's
    surprising what you can get out of stereo) Spatial crescendos have
    much more impact than just amplitude crescendos. Also, as an interface
    thing, considering x/y separate from distance can allow you to build
    things that are musically interesting, though perhaps less perceptually
    accurate. (such as a loud sound that's moving from speaker to speaker,
    or a very distant sound that's in all speakers equally)
    Stability versus speed: some things that save CPU can also be less
    stable, so be sure to stress test them to make sure. Oftentimes people
    try to do things at the control-rate (such as LFOs) to save CPU, and
    this works to a certain point, but after that you tend to get into
    diminished returns. (especially if you're having to interpolate lots
    of values) CPU spikes from a flood of control-rate data can bog down a
    patch, too; generally speaking, the audio rate is much more stable
    because it generally runs at the same speed. Vexpr is a great way of
    streamlining mixing/spatialization tasks. Also, once you're doing a
    lot of audio processing, the control-rate can be less dependable
    timing-wise. (unless you're using audio interrupt, but there's more
    overhead for that)
    Sometimes processes can be more or less functionally equivalent.
    Having a reverb before a filter bank may work the same as that huge
    filter bank you were trying to use, or if you're using a bunch of
    detunings, see how much different a chorus on the output is from what
    you're getting. I use pcontrol for doing muting/unmuting, and have
    found it to be very dependable, but there are lots of other ways to do
    it.
    omx.4band~ can be very useful at the final output stage.
    Trigger is really important to use to control the order of control-rate
    processes. As a general rule of thumb, if I'm sending one value to
    multiple places, I use trigger to ensure that regardless of how things
    get moved around, the order is preserved, and this goes double when
    dealing with send and receives.
    A very soft ping-pong delay, particularly on synthetic processes, can
    be very helpful at adding depth to the sound. If you use a windowed
    delay, you can change the values over time with a metro and a drunk;
    this keeps it from getting too predictable. This is also a great trick
    for thickening up a granular sound.
    A high-shelf filter using biquad~ can change the color of a sound
    significantly by functioning like a lowpass or high-boost.
    Ranges of values are more interesting than singular values for almost
    anything, and rand~ is great for this.
    If you use fiddle~, use a poly~ to wrap it. That way you can run it at
    its desired vector size of 64, and run the rest of the patch at
    whatever vector size you want. (I use 256, just because I'm on an
    older machine and trying to wring as much as I can out of it)
    Preset systems are good, but are not necessarily musical. Sometimes
    just changing a few values at a time via a mapping process can be very
    effective, and your preset system should be flexible enough to
    accomodate this where practical. Having a way of naming presets can be
    very useful as a reminder as to what they do. Having multiple ways of
    accessing the same value is a good idea. i.e. a global receive and a
    local receive would allow you to set all the filter Q's, or just the
    one filter Q.
    Rigorously stress-test your patch. Leave it running overnight, try
    unexpected inputs, etc. Do anything you can to simulate performance
    conditions. (sometimes I'll add a little bit of the output back into
    the input to test it for microphone bleed)
    It's good policy to name all your abstractions such that they begin
    with a unique identifier. (mine all start with PM.) Otherwise, if you
    send the patch to someone, they may have a different patch with the
    same name and havoc ensues... Eventually, if you're going to send it
    out, it's probably a good idea to consolidate abstractions into
    patchers where possible, so that there's a minimum of "which patch?"
    and less potential for naming conflicts.
    Envelope followers can be great for mapping, particularly if you add a
    layer of abstraction to them, by having them control the speed of a
    rand~, cycle~, etc., or even just delaying them by a few seconds.
    Also, independent amplitude LFOs can be surprisingly effective when
    combining synthetic sounds.