Conference napalm::commusic_v1

    Sounds pretty twisted to me ;-)
    
    Not having a Proteus, I haven't tackled quad in quite that way.
    
    I did do a quad project with my stepdaughter and her classmate, both
    art students.  They wanted a 'surround sound' metaphor for a
    performance art piece.  After me telling and showing them some of the
    musical and sound effects sounds I had, we laid it out on paper.
    
    About 7 minutes long.  I dubbed nature sounds, car crashes, drums,
    dialog fragments, you name it, onto individual tracks on my 8track.
    I then routed some of the channels to one stereo mixer and some to
    another.  Each mixer's output went to a separate stereo cassette
    recorder.
    
    After cueing up the cassettes, I began the mix onto two cassettes at
    once.  Later, they played the two cassettes on two boom boxes with
    detachable speakers for genuine quad.  Fine art ?  Nah.. just fun.
    
    karl
    
    p.s. It WOULD have been fine art if I'd generated it randomly using a
    computer, right ?

    Howzabout trying a velocity crossover between one patch and another?
    If the two patches were assigned to different outputs you could
    control them via velocity...
    
    Edd
    

    
    	Given that many new "Video" recievers have surround sound decoders
    does anyone know how to encode the sound ?  What type of harware is
    required ?
    	
    		Steve P.
    

    Not really inkeeping with the exact topic, but what the hell....
    
    I was only a kid when quad came and went. It never really got anywhere.
    Why was this? It seems to me that the problem wasn't technology, or
    price, so much as people just didn't want it?
    
    What do you all think? (did anyone actually buy a quad system?)
    
    tony 

> Sounds pretty twisted to me ;-)

It is, but at least I'm not corrupting the minds of young female art students!
8^)

>    Howzabout trying a velocity crossover between one patch and another?
>    If the two patches were assigned to different outputs you could
>    control them via velocity.
..
 
Is that possible on the proteus?  There is an XFADE function. I don't
know how to do it across linked patches. One thing that prevents me
from experimenting is the lack of a velocity sensative keyboard.

>    Not really inkeeping with the exact topic, but what the hell....
    
>    I was only a kid when quad came and went. It never really got anywhere.
>    Why was this? It seems to me that the problem wasn't technology, or
>    price, so much as people just didn't want it?
    
>    What do you all think? (did anyone actually buy a quad system?)
     
Sure, this is on the topic. You must be young, it wasn't that long ago!
Or, maybe I'm just OLD. Gad!

I didn;t get sucked into buying a system. But, a receiver that I bought in
1974, did have some hoaky feature that supposedly simplifying upgrading it
to quad. I never believed it, nor did it play any part in my decision to buy.

The technology was rather poor. LP's were "the big thing" then, and quad LP's
had a wear out problem, caused by the increased, and more critical grove
tolerences, and bumpies (what do you call the irregular surface
in record groves anyway?). If your cartridge and needle were not perfect,
no quad. 

They did have quad FM receivers, but there weren't a lot of stations.

I'd probably blame it on less than satasfactory hardware technology, and
an extreeme lack of software. The quad effect was not very dramatic anyway,
and the added cost of speakers, and channels didn't quite excite the
masses.

I'd guess that with todays technology, it would be much more popular.
But, who knows.

    Re: .4
    
    Ha ha ha ha ha
    
    I still own a Pioneer QX949 top of the line quad receiver circa 1974, a
    Lafayette quad amp, a Sony quad open reel, Pioneer quad *headphones*
    and about 30 or so quad albums on LP and open reel.
    
    What happened?  The record companies dithered and went "dual format". 
    The quad albums cost an extra buck and were separate pressings.  I.e.
    you could buy weither stereo or quad.  If they had just gone and done
    quad albums only, things might have been different.  I should also
    mention that there were three LP systems, SQ (CBS/Sony) (QS, Sansui,
    also known as "Regular Matrix") and CD-4 (RCA/JVC).  The CD4 had the
    best separation (each stereo channel was essentially a stereo FM
    program, demux to get four channels) but the high frequencies needed to
    multiplex the back channels was a pain to cut into vinyl.  Most CD4
    pressings were noisy (pops, crackles).  The SQ and QS matrix systems
    had inferior separation (but could provide "synthetic" quad from stero
    sources).  
    
    None of these worked with tape because they relied on tricks like
    multiplexing a carrier at 38 KHz (well out of tape's range) or using
    phase encoding (bad move considering cassette's tendency for phasing
    problems), so tapes went "discrete" for open reel and 8-tracks,
    while cassettes never happened because Philips refused to license
    four-in-one-direction track schemes which were incompatible with
    stereo machines (Portastudios get away with it because they are
    "special purpose").  
    
    Also, the FCC never could decide on a quad radio format (although many
    stations went with SQ).  My reciever even has a jack to plug in an
    "optional" decoder for quad FM which was expected to come along any day
    back in 74.  
    
    However, quad is still with us thanks to home theaters and Dolby
    Surround Sound which has me wondering whether to laugh or cry as people
    line up to pay $$$$$$ to have quad television commercials while they
    could care less about quad *music*.  Sigh...  
    
    Notice also that the manufacturers, both hardware and software learned
    *something* from the disaster, and applied the lessons well in
    introducing the CD (namely stop selling the old stuff and people will
    flock to the new).
    
    Edd Cote might want me to hook all that crap up some day so he can hear
    the first three Steely Dans in quad, not to mention Pink Floyd's DSOTM,
    some Pharoah Sanders, Sanatana's "Abraxas" and a number of other
    mindbenders.  I still have my system, now driven from a stereo amp,
    hooked up in the old Hafler "Dynaquad" ambience recovery configuration. 
    I really don't like stereo by itself, it sounds flat.  
    
    						Brian

What's the point of quadrophonic sound, anyway?

1) You only have two ears.
2) Using THREE speakers arranged in a triangle, you can produce any effect
	that four speakrs can produce.

	1

        
        O 
   
   
   2         3


For example, consider the arrangement above with the listener facing speaker
one. For a sound that's coming from directly behind the listener, speakers 2
and 3 would output the same level.
     For a sound coming directly to the left, most of the output would come
from speaker 2, with a little sound from speaker 1 to offset the sound from
behind.

Would this work? I could be totally wrong.

- Jim

    
    If ears were perfectly omnidirectional, triphonic sound might be
    sufficient to produce surround sound.  But, most human ears have
    specific pickup patterns which are a result of ear canal geometry and
    ear lobe shape.  This additional shaping of a sound's component
    frequencies provides more cues for the brain's attempts to locate the
    sound source.
    
    The perceived sound stage used to be a significant part of the
    listening experience for me, but lately I'm more involved in the
    composition and performance aspect.  I suspect that the reason quad
    didn't catch on was the lack of added value for the extra expense and
    inconvenience.  But, for some situations, like the performance piece
    previously cited in this discussion, there is no substitute.
    

	Any sounds can be replicated with ear phones in stereo.
	Especially if you neglect head movement or account for it by changing
	the sound as the head moves.  This is probably the correct thing to
	do.  A CD should encode individual sound sources with position;
	then you could enter your position relative to the ensemble, and
	have a wireless head set that detected your position and adjusted
	the sound accordingly.  Neglect Doppler.
Tom

    re .9
    To make this work, you would need to make the time delay for each
    source consistent (with reality), for the paths from each source to
    each ear. I read an article about some researchers who did just this;
    they found that you get perfect Doppler from the system for free as a
    side effect of changing the time delay to accomodate movement of the
    source(s) or listener.
    
    I believe they were researching sound source movement, both direct
    path, and some number of reflected sound paths. 
    
    I can dig up the reference for anyone interested.

    re .8
    
    Researchers have found that there is a strong notch filter effect in
    human ears, due to the shape of the outer ear.  The position of the
    notch varies as a function of the angle of entry. I think the notch
    shifts to lower frequencies as the angle moves from straight ahead
    upwards to over the listener's head.  They demonstrated by synthesis
    that the subjective height is encoded by this notch.
    
    The front to side angle is encoded by two variables: the relative delay
    between the listener's two ears, and the low pass filtering effect from
    turning one's ear away from a source.
    
    These two variables give you enough info to tell 2 out of the three
    dimensions that relate the listener's position to the source's
    position. The missing dimension is the distance between them: that has
    been found to be a function of the relative volume, and the amount of
    reverberation present. Distant sources have more reverb than closer
    ones.
    
    
    Adjusting the relative delay between the left and right signal of a
    stereo pair is much more effective than merely adjusting the relative
    volume. If you had a mixer with delay control, and an adjustable notch
    filter, for each source, you could do some dynamite 3-D mixes!

    I was at the Electronic Music Studio at Dartmouth last month (where I
    studied ages ago). When I was there we had a four-track system with
    four speakers and a color organ in the ceiling. 8^)
    
    Now there's a graduate student doing experiments with spacial sound
    using a virtual-reality type glove as a controller.
    
    -Ross

    
    	Long, long time ago, back when I was a sophmore in high school, I
    worked with a fella that was building a quad panning system for John
    Cage or somebody. The idea was to have these dancers and pan the music
    each person was dancing to around the room, following the dancers
    movements. This was in the mid 70's - sounds like something Cage would
    do. 
    
    	I was into the idea of "location modulation" back then and devised
    a system to route signals to amplifiers using two quadrature control
    signals - two signals whose relative phase would result in the location
    (speaker) the sound source came from. I set up an experiment similar
    to .0's in my yard one time using records for the input, until the
    neighbors complained. I could spin the sound around left or right,
    or do this crosshatch pattern.
    
    	I really thought it would be fun to have the music hop around
    in the space (an extension of the then-popular "ping pong" effect),
    front to back and side to side - with a decent correlation to the
    musical passage. I wanted to write Chick Correa and Frank Zappa
    to tell them of my idea - cause *their* music would really be fantastic
    using this - but never bothered, thinking they probably never listen
    to me anyway. Then quad died.
    
    	I hear that there's a format laid-out for CD players in quad.
    This would of course have perfect seperation and all. I think with
    the advent of the ambience processor any chance for quad systems
    as defined in the 70's is small. Unless people suddenly get into
    sounds zinging around the room, in one ear, through their brains
    and then out the other as something desirable in listening to music.
    
    	Joe