🚀 go-pugleaf

In article <1992Dec31.090155@trc.amoco.com> znpt01@trc.amoco.com (Norman P. Tracy) writes:
>
>All engineering is the art of trading off compromises.  In box speaker
>design the three basic tradeoffs are: 1) efficiency vs. 2) bandwidth (how
>low does it go) vs. 3) distortion.

Actually, there are two sets of triple-tradeoffs:

The first, which defines the "small signal" tradeoffs are: 1) efficiency
(how much input electrical power it converts to sound power), 2) bandwidth
(how low it will go) and 3) box volume.

The second, which define the "large signal" tradeoffs, are: 1) woofer
diameter (how much area the cone has), 2) Linear excursion (how far can
the cone move before it distorts and 3) Maximum acoustical output

The two groups are closely related through the bandwidth in that for a
given cone diameter and excursion capability, doubling the badwidth (going
an octave lower in cutoff) results in a reduction of 12 dB in maximum
acoustical output at the respective cutoff frequencies. Or, to achieve the
same acoustical output at 25 Hz that you have at 50 Hz requires either the
same cone area with 4 times the excursion capability or a woofer with
twice the diameter and the same excursion.

So Norm's conclusions are essentially correct. I just thought I'd add a
bit more of the cuzwhy's to the discussion.

>The speakers impedance and power ratings are only a very indirect
>indicator of how the designer picked these tradeoffs.  Without Dick Pierce's
>experience and test equipment the best most of us can do is listen to the
>EXACT combination of source/amp/speakers before plucking down the long green.

Yeah, though even the best of us can be fooled at times.

Norm's recommendation is essentially correct. The best way to decide is to
listen to the exact combination you're deciding upon. Find a dealer who
will either loan you equipment or has a liberal trade in policy. Listen to
things in YOUR room with YOUR music at the levels YOU like.


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