Conference napalm::commusic_v1

    No real instrument is a point source.  Placing an instrument in
    the stereo field by panning a mono source is a crude approximation
    of reality.  It's more than just "recording ambience", it's the
    actual sound we're talking about here.  You can cover up some of
    the "point sourceness" by adding room/hall ambience with a stereo
    reverb, but that's just a coverup.
    
    How valuable is the result?  Well probably no more of an improvement
    than stereo was over mono.
    
    Stereo samples require twice the storage of mono samples.  Depending
    on your perspective, this might be construed as "too" large.  Any
    decent stereo sample ought to allow full exploitation of paired
    uncorrelated mono samples (cf. the proposed mechanisms in my ultimate
    drum machine), so *you* can decide how to use/abuse your sample
    memory.                           
    
    len.
    

    
    
    My EPS is supposed to do 'stereo sampling', sort of. At least, what
    you end up doing is having two wavesamples attached to the same
    base note(s), and panned L/R (or 1/2)... I don't know, it sounds
    great but for all the reasons in .1 I agree, it's not exactly a
    big deal, and I certainly won't be making lots'n lots of stereo
    samples.
    
    /pjh

    Well, gee, len, since the sound of a Bb clarinet is differnet from
    every angle, just how many reocrdings and what steradian granularity
    should we sample for one instrument?
    Tom
    ~/~ ;-) ^^^ 
    Mono is fine, plus panning and stereo reverb.
    Tom

    I heard a stereo sample of an F-16 flying overhead that was done on the
    Emulator III.  Quite impressive, but I doubt that it will ever be as
    popular as an orchestra hit. 

    I guess I don't see what the big deal is, either.

-b

    Now, an orchestra hit should be a stereo sample, because it's
    distributed in space, I mean the orchestral instruemnts are.
    But a violin?
    Tom

    As always, the exercise of good judgement entails knowing just when
    to stop.
    
    Stereo sampling is occasionally worthwhile.  For modest additional
    complexity, a sampler could offer you the choice of stereo or mono
    sampling.  It should not require you to use one or the other.
    
    ~/~ duly noted, but ...
    
    Consider the following admittedly contrived situation - a sample
    of a full orchestra hit.  Would a mono point source sample, panned
    with stereo reverb, really suffice?
    
    And yes, the sound field varies from point to point; we all know
    that.  The point (uhm, excuse me) is that the replication of the
    ambience of that field is greatly helped by stereo.  It is not greatly
    helped much more by additional channels.
    
    Taking Tom's point to the limit (remember what I said about judgement),
    we really don't need stereo recording, because it can never perfectly
    duplicate the "real" three dimensional sound field associated with
    any instrument, and besides, just throw a stereo reverb on your
    "mono" to hoke up a stereo image.
    
    len.
    

    I agree that we don't need stereo at all.  All of the musical
    information a Mozart symphony comes over monaural AM broadcast.
               Tom

    Let's abolish color movies and TV, too!

    Well, so far it's great, hohum, and forever mono...
    
    My point, poorly expressed, is this: sampling is primarily used
    to record a single note of an instrument, and then allow it to be
    played back, triggered by MIDI, over a controlled transposition
    range. If the instrument, like a harp or grand piano, has a large
    frequency range, then many individual note samples and their xposition
    range are set end-to-end, and thus can respond to the corresponding
    incoming MIDI note numbers.
    
    So tell me, aside from the dread OrcHit, what single-note musical
    event requires stereo recording ? Remember if you record a lot of
    room ambience, you'll really get sludge when playing a rapid passage.
    
    I guess I *DO* think that setting individual note/range PAN positions
    thru software is 'good enough'. Even if you did have a bunch of
    REAL stereo samples, the sound origination point has to sit somewhere
    between the speakers.. and unless you could pan in software, that
    point would be right in the middle. Gee.. just like mono.
    
    karl

    I have to agree 100% with Karl on this. Stereo sampling...BFD...I'm
    not impressed. I'd much rather have all that extra memory to spread
    out over additional multisamples-- or to have many sets of
    multisamples able to be layered-- or having many different sets
    of multisample instruments able to be accessed instantly with the
    touch of a single
    button (this would be particularly useful to me since I play out
    a lot). Gee....sounds like I'm looking for a mono EPS...
    
    Mike D 

    I just saw Karl's personal_name go up 3 degrees in 2 notes!!!
    
    What's happening out there?? Having a meltdown???
    
    ...tepid 84 here today, slight breeze up here on the Mount.
    
    Edd

    uh, digression.. set a new record in downtown Tucson yesterday.
    
    112 in the shade.
    
    No wonder I'm a little slow.
    
    karl

    
    re: Mike D.
    
       Well, the EPS is really one of those pseudo-stereo output boxes
    anyway. I'm still figuring it out (they still haven't sent the manual,
    would you believe?) and I don't have the 8-out expansion, but the
    two outputs if has can (stereo drum roll, please) pan, cross-fade
    stacked samples, and (sound of lots of people yawning in stereo)
    play it all in mono. I dunno. I'd rather do my panning from the
    mixer, the stereo samples sound great, but, what a gimmick.
    
       What sounds would I sample in stereo? 
    
       how about:
    
       a loop featuring a chorus of crickets and frogs
       a freight train going by at 70 mph (loop the cars passing)
       split a piano so the low notes come out the left and as you move
         up the keyboard the notes start going to the right
    
	okay, so I'm reaching a bit.
    
    
    /pjh       

    The Ensoniq rep. demonstrated with great facility how the panning
    funtions can be use to create a stereo mix on the EPS, and even
    on the ESQ1.
    
    On the ESQ1 you can modify your patches to have fixed positions in
    the stereo field.  Then you create your mix by which patch you use.
    
    I think stereo sampling would have it's place, but not for everything.
    It's sort of pointless when you're going to use a synthetic ambience
    on everything anyway, right ?
    
    

    did you ever mix the outputs of a stereo reverb together and loose
    the reverb because the right-side reverb is the inverted version
    of
    the left-side reverb?  That's what the SPX90 does.
    apparently.
    I mixed the outputs together and gotthe input w/o reverberation
    emulation.
    Tom

    It doesn't seem like anybody's been listening to what I actually
    said.  I didn't say stereo was great.  Nor did I say it was necessary.
    I said that with modest additional complexity, a sampler could let
    you choose whether or not to use stereo samples, and how to use
    them if you did.
     
    Also, a stereo sample need not be centered.  As I proposed in my
    ultimate drum machine reply, you can place a stereo sample *anywhere*
    in the stereo image by "squashing" it as it gets closer to the left
    or right extremes.  Placement and spread (apparent size) are independent
    parameters.
    
    It remains true that *no* real sound source is a point source.
    The sound of a harp does not originate from one point on the string;
    a lot of the sound comes from the sounding board.  Listen to a mono
    source panned to a single point in the stereo image.  Listen
    through headphones to make the point more obvious.  It sounds unreal.
    It sounds spatially compressed.  Maybe if you have a lot of such
    sources, it's not so obnoxious.  But it sounds *much* more realistic
    if there's at least *some* stereo spread to the sound, regardless of
    where it's panned.   But then again, these are synthetic instruments,
    so their ambience must sound synthetic too, right?  I mean, nobody
    actually plays these things except into a mixer, right?
     
    If point sources panned across the stereo image were as adequate
    as many seem to be claiming here ("just throw a little stereo reverb
    on it"), then I am hard pressed to understand why anybody bothers
    with any form of stereo output for anything.  Oh, yes, I forgot,
    the only reason engineers design such features is because the marketing
    guys forced them to.
           
    len.
    

    re .16 - the SRV2000 has two completely distinct reverbs in the
    same box.  When you mix the stereo outs, you get a denser reverb.
    
    Just because many manufacturers "cheat" with fake stereo output
    doesn't defeat my point.
    
    len.
    

    The effect of panning a sound across the sound field is a different
    point that sampling in stereo.  Panning with amplitude is phony
    becuase the phase in each ear doesn't change as it moves.  A real
    clarinetist walking across the stage playing about an A440
    cause a changing phase in each each as well as some amplitude change.
    The phase change is probably more important than the amplitude change.
    Moving sources are a different problem.  
    
    However, the fact that mixing mono into stereo also makes the same
    phase into each ear can contributte to flatness, I imagine.
    Probably, a good panner would change a delay in a range of
    0-50ms as you panned all the way from left to right, in opposite
    direction for each ear.  So, at even mix left to right, the
    amplitudes are equal and the phase change for each channel is zero
    time.  All the way clockwise would be maybe 100ms retardation for
    the left channel and no amplitude (so let's get another example).
    Let's say a mix knob is at 3 o'clock.  The right channel would be
    advanced say 25ms and amplitude say 24dB louder. (probably too much).
    The left channel would be retarded 25ms and 24dB softer.
    A pan should change phase as well as ampltitude.
    So cheap small 100ms digital echo/reverbs could be used to help
    pan mono sources.
    Tom

    Not only should it be delayed, but it should also be lowpass-filtered
    (to mimic the shadowing effects of a human head).	
    	
    Gee, this is exactly what a sonic hologram generator does...:-)
    
    

I see stereo samples useful for freeing up effects.  For example, load your
favorite mono sample into your sampler, route it through your favorite stereo
effects unit, and route it back to the sampler.  Tell the sampler to sample
itself in stereo (can off the shelf units do this, given enough memory?).  You
now have an ambient stereo sample (after some twiddling with loop points, 
perhaps), and your effects unit is now freed up.

Stereo sampling is also useful if your sampler supports direct-to-disk
recording since it is really being used as a stereo digital recorder.  And
since this seems to be the wave of the future for samplers/music_workstations,
it looks as though stereo sampling has arrived to stay.

Of course Len's proposal of supporting 'double length mono' should be 
mandatory in any stereo sampler.  Which means that they really should be
called 'Stereo Capable'.

Todd.

    re .19, digidelaying one side when panned mostly to the other..
    excellent idea, Tom.  It is of course just an offshoot of some of
    my notes from a couple of years ago re depth in stereo productions..
    
>< Note 1480.14 by ARGUE::HARRIMAN "Hell's only command: 'SET'" >
>       What sounds would I sample in stereo? how about:
>       split a piano so the low notes come out the left and as you move
>         up the keyboard the notes start going to the right

    Pete, I already have several keyboard setups that do this, implemented
    on MONO samplers (Emax and Kurzweil) which have stereo panning
    capability.  True 'stereo sampling' means that EACH NOTE sample
    has two separate digital waveforms, played back in exact
    synchronization.... in your scenario above one can emulate the 
    width of the keyboard easily by software location
    of the apparent sound source... from MONO sound sources. You seem
    to have confused stereo sampling with stereo multisample playback.
    
    A picture of stereo multi(mono)sample playback:
    
             |         |         |         |         |         |  
     sample 1| sample 2| sample 3| sample 4| sample 5| sample 6| sam..    
range        |         |         |         |         |         |  
    A-1 to A0|A#0 TO A1|A#1 TO A2|A#2 TO A3|A#3 TO A4|A#4 TO A5|A#5...
             |         |         |         |         |         |  
Pan val: -7  |   - 4   |  -2     |    0    |  +2     |  +4     |  +7..    
             |         |         |         |         |         |  
    FAR LEFT            ---- panning position -----            FAR RIGHT        

    karl

    ..even the lowly FZ1 does this.
    
    Richard.

    
    re: .22
    
      point taken, I guess, although it would seem to me that you could
    do it either way. Just as well, since it's more complicated as a
    stereo sample (albeit multisampled) than as a mono-panned sample.
    
      Actually I have one that does this also, in mono, courtesy of
    Ensoniq. My Kawai piano sample is in lowly multisampled monophonic.
    
    /Paul_j_harriman