Conference napalm::commusic_v1

    From a power point of view (and this is probably nothing of value here), 
    100W into each of two speakers is the same amount of power as 200W into 
    one speaker.  But, as far as what you hear goes that may be another story 
    as near as I can tell.  That is, acoustics probably come into play and can 
    cause results to be skewed many different ways.  Also, if any of the
    sound equipment (amps, speakers or enclosures) are not identical there 
    could be many things (such as different frequency responses) that could
    cause the system to sound louder at different speaker locations, listening 
    locations or at different frequencies.  Not sure that I fully understand 
    the question ...
    
    Steve

    Another interesting effect is due to geometry of sound propagation.
    With one speaker, the intensity falls off with the square of the
    distance.  If you made a long line of speakers all the way across in
    front of the audience, than for medium small distances the intensity
    would fall off only by the distance.  If you made a big wall of
    speakers (including in front of you) everywhere extending infinitely in
    all directions, it would never all off no matter how far away the
    audience was.  I tried this when I was 2�.  Worked great but it cost a
    bundle.
    Sure you can pump twice as much audio power into the atmosphere with
    two equal speakers, but the signals will interfere in different ways
    at different frequencies, sometimes reinforcing sometimes cancelling
    and in-between, even if they are wired up the same polarity.
    Expect the power to be RMS of the two speakers, or about 41% higher
    power, or about 1.5dB.  Remember folks, that's by power, not voltage. 
    If we had doubled voltage or current at the speaker, that would have
    been 6dB; 41% more 3dB.
    Tom

    I guess I wasn't real clear about the question, I'll try to clarify it
    a bit.
    
    The argument seems to state that you can get higher overall sound
    levels from a 2 ch amp if you use the two sides in biamp mode rather than
    running them in parallel (I don't mean bridged). Is this true?
    
    If I have a 2 ch power amp that drives 2 speakers, 1 speaker/channel,
    will I be able to generate higher sound levels by adding a crossover
    and using one channel for low and the other for high frequencies?
    Assume that the speaker impedences seen by the amp are the same in
    each case, and assume equal efficiencies in the speakers in each case.  
    
    I hope this makes it a bit clearer.
    
	Ron

    I guess no one knows, 2 weeks having passed, but I'll hazard a guess
    that it doesn't make any difference. Assuming all other things being
    equal (e.g., each single driver has the same frequency response as the
    crossover/driver-pair combination),  I'd even argue that since the
    crossover can't be 100% efficient, the "uncrossedover" hookup delivers
    more power to the drivers, and if the drivers are equally efficient,
    more power to the listener's ears.
    
    len.
    

    Well, it's an apples and oranges thing, isn't it?
    
    Assume you have a sound source with lots of bottom and little high end.
    Let's say 80% of the energy is below the crossover, 20% above.  This
    means when biamping, the low end system has to generate considerably
    mor epower than the high end system.  Now, go run the rig in parallel,
    you will get considerably more volume, since the low end can now draw
    from *2* amps.  If we started out assuming the drivers were identical
    (like in a bass amp where 4-10 cabs are used for both low and high
    end), then biamping would not provide more usable volume *in this
    instance*.  A more even distibution of energy across the frequency
    range changes things.
    
    An interesting aside:  in biamping of bass guitars, it has become
    common to sell amps that are not matched "stereo" pairs, but have more
    low end power than high end.  Examples are amps from Gallien Kreuger
    and Trace Elliot which drive 250-300 watts into the low end and only
    100 watts into the highs.    
    
    							Brian

    Contrary?  I think we agree (for different reasons) that biamping
    *doesn't* provide more volume.
    
    len.
    

    
    Back from vacation. Biamping doesn't always give you more spl, in a
    strict sense. What Tom says is true, it can be additive or subtractive.
    Biamping a good two way system that has an excellent passive crossover,
    can sometimes sound worse. Because the passive crossover has more than
    simple crossover functions. There may be pads, phase correction, and
    other functions that your run of the mill electronic xover will not
    have.
    
    What biamping usually gives you is not more volume, but more headroom.
    The passive crossover will get saturated at some point, which is the
    spl limit of the system. An electronic xover will not saturate so the
    sopl limit is the limit of the driver itself. 
    
    You can actually get less spl when biamping, as Brian noted. If you're
    only using 10 out of the 100 watts on the high end channel, that's 90
    watts sitting there which the low end channel could be using. At least
    this is true for a pro, dual mono amplifier.
    
    CdH