Seeking listening help in Austin area

Hi Spencer,

I'm afraid that you do not get as much SPL increase from moving closer to the SoundLabs as you do with conventional speakers.  Likewise you do not get as much SPL decrease as you move further away.

The reason is, the big SoundLabs do a good job of approximating a line source, while most conventional speakers approximate a point source.  SPL falls off by only 3 dB for each doubling of distance from a line source, as compared with 6 dB for each doubling of distance from a point source.  Likewise SPL increases by only 3 dB for each halving of distance from a line source, versus 6 dB for each halving of distance from a point source.  These numbers don't take the contribution of room reflections into account, but these trends hold up well in a home listening room.  

In fact, at very close range, the SoundLabs approximate a planar source, with virtually ZERO change in SPL as distance changes!  The difference in SPL in going from 1 foot down to 1 inch is negligible. 

Duke

@geoffkait , It looks like I misunderstood what you meant by "twice the volume".  

It can mean "subjectively twice as loud", which is generally considered to be +10 dB.   That's now I'd normally use the term.

But it can also mean "equivalent to doubling the amplifier power", which would be +3 dB, which is indeed what we'd get from sitting half as far away from a line source.

Duke