[Lf] Radio Shack "Magic Speaker"

[Chuck Rippel]

It was goot to meet Frank, Andre and the rest of the crew while 
they were down in Nags Head, NC.  For myself, the highlight was 
hearing the Indian station on 18.2 khz.

The SWBC community has long enjoyed a series of speaker 
available from Radio Shack.  The Optimus Pro-7 features a ported, 
4" driver and 1" dome tweeter.  The cabinet was made of sturdy, 
cast aluminum.  The ported design made it extremely easy to drive 
with the 1-2 watts available from receiver audio amplifiers and the 
sound very detailed.  

It is important that the speaker uses a 4" radiator.  It was found 
during a study by JBL sound that specifically this size driver 
provides optimum reproduction and sonic dispersion of voice 
frequencies.

Unfortunately, the Pro-7 was discontinued some years ago.  
However, Radio Shack has again began to market that very same 
speaker under the model number, Pro-X44AV.  Selling for $59.99, 
it is listed in their 2000 catalogue on page #130.  There are 2 
different catalogue numbers.  40-2080 denotes a black speaker 
and 40-2081 gets you a speaker finished in white.  Frequency 
response is spec'ed at 90-20K cps and the impedence is 8 ohms.

I have heard but not checked into the rumor they are currently on 
sale for 1/2 off.  YMMV.


  
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Chuck Rippel, WA4HHG
R390A List Co-Administrator

Reply to: wa4hhg at amsat.org
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