[Elecraft] "lousy audio" ?

[Don Wilhelm]

Deni,

Actually it has already been done.

Tom Hammond has a design with minimum components on his website that 
uses a TDA2003 audio chip.  Look in the General Amateur Radio files 
section at www.n0ss.net.  That is the one I am using.  Plenty of audio.  
I am driving it into two paralleled 5 inch woofer 9 ohm speakers and it 
works great and I switch in a 'tweeter' which consists of the same 
speaker used in the K2 (Jameco 99996) when I want more high frequency 
response for SWL Broadcast listening - my 'tweeter' is connected with a 
series 40 uF non-polarized capacitor.  My woofers were a special buy 
that I made many years ago and are not readily available, so my speaker 
setup is not readily reproducible.

My prior amplifier used only one of the 9 ohm speakers and also worked 
fine.  More power is available with lower impedance speakers (or in my 
case a paralleled pair). 

The frequency response will depend on your speaker choices and the 
enclosure - a bit of experimenting may be in order to obtain what you 
want to hear.  A metal enclosure and ferrite beads on the inputs can 
produce the RF Proofing, but I use a wood cabinet with the speakers to 
control resonance effects.  The electronics can be inside a shielded box 
if you encounter RF problems.
Maybe someone will come up with details of an enclosure design using 
available speakers.

73,
Don W3FPR

F5vjc wrote:
> So, how about someone comming up with a good communications quality
> amplified speaker and enclosure design, RFI proof of course!
>
> I would build one...I believe there was/is an Elecraft design but it
> looked overly complex...
>
> Anyone care to suggest a suitable audio chip, speaker and enclosure?
>
>