On Fri, 16 May 2008 12:38:03 +1000, Tony <tony@[EMAIL PROTECTED]
> wrote:
>www.billfitzmaurice.com
>The DR-200 and DR-250
The model 200 looks like an array of piezo tweeters with
some un-named other drivers in a ported box. The claimed
104 dB SPL/1W/1M sensitivity is actually possible in this
volume and with the claimed about-190 Hz pole.
It would require lower-range drivers of 98 dB/1W/1M
sensitivity if four drivers were connected in series-parallel,
maintaining the impedance of a single driver and the
ability to connect safely to conventional amplifiers.
Or, it could be made with four drivers of conventional
but high-ish (in this case, 92 dB/1W/1M) sensitivity
connected all in parallel, presenting a possibly
dangerously low impedance to the driving amplifier.
Stick an OhmMeter across the terminals, and report back.
A number around an Ohm will be fine for a pro-sound
amplifier designed for that gig, but death for anything
less.
I can't in good conscience say anything comforting
about the DR250. Too many holes, too bogus. Just my
personal take, of course.
I can almost believe the asymtotic 160 Hz knee in
that size folded horn, but the sensitivity (a *very*
difficult to both measure and, even, to define, number)
of 106 dB/1W/1M is *way, way* biggie big.
To put it in context, the Klipschorn was (pretty much
honestly) rated at 104 dB/1W/1M and the highest
sensitivity drivers made (which closely approach
the theoretical maximum) are rated at an agreed-upon
number of 110 dB/1W/1M. The last number is equivalent
to about 30% conversion efficiency, an amazingly
big number in the scheme of things. And both at
conventional impedances.
Well, you wanted opinions; like assholes, everybody's
got one. Please forgive if mine is too public.
All the best fortune,
Chris Hornbeck
"I have a gift for enraging people, but if I ever bore you,
it'll be with a knife." -Louise Brooks
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