v127p9xg@ubvmsa.cc.buffalo.edu (Robert J Miskines) (10/05/90)
I have heard of this improvement as well. I did a little digging, and found
that all that was necessary was re-routing the PC's speaker output through
a 4.7uF Electrolytic capacitor to your stereo/amp. It truely does wonders.
However, although this is a simple modification, take into account that there
are very few software packages out there that provide sound of any ddecent
quality. Honestly, they (the software companies) expect the sound to be
heard through that 2" squeeker, so even if they did include good sound effects,
they probably wouldnt be heard anyway.
But, on to the installation....
First, locate the connector where the speaker connects to the motherboard.
It may be noted in the manual for the motherboard, or you may haveto
employ a DC voltmeter.. anyway, determine the polarity of the signal. Although
it IS audio, it is not AC. the digital logic, as used by IBM and clone
makers, only provides DC..
Cut these (2) wires. strip 1/2" or so from each of the 4 ends.
Cut (2) pieces of 'hobby' wire, 18 ga or so, each approx 12" long.
Strip 1/2" insulation off of each of these 4 ends.
Twist together (1) the negative output from the motherboard
(2) one of the wires leading to the speaker
(3) one of the ends of one of the 12" wires
make that connection permanent by either soldering, using a 'wire nut' or
some form of crimp connector. Insulate with electrical tape so it does not
contact anything else within the computer.
get a single-pole double-throw switch. This will have 3 terminals, in a row.
To the center terminal, solder the motherboard positive audio out.
To either of the outside terminals, solder the other speaker lead.
To the remaining outside terminal, solder the positive end of a 4.7uF
electrolytic capacitor.
Solder the negative terminal of the capacitor to one end of the other 12"
wire.
Connect the other end of that wire (from the capacitor) to the center
terminal of an "RCA" jack (also known as "Phono"). this is the type of jack
you have on the back of your stereo/amp for interconnecting other 'stuff'.
To the outer/case terminal of the jack, connect the final loose end.. This is
an end of the wire you twisted together with the motherboard (-) and a speaker
lead.
schematic follows...
o-----------|(------O RCA center
| + ^capacitor
|
o o----------O RCA case
|
|
o-----------------------o--->o--------|----------O Spkr out(1)
SPDT switch ^ |
^Mboard "+" |
vMboard "-" |
o-------------------------------------o----------O Spkr out (2)
Now, the switch will obviously select where you want the output to go.. speaker
or stereo. Use a 'phono' 'Y' to bring the signal into both channels of your
stereo/amp.
DISCLAIMER: I suppose this wont mean much, but..
I have installed this modification as described on my IBM AT
compatible, and several of my friends with compats mfg'd by other
companies have installed it as well with no problems. However,
I cannot and will not make any guarantees as to what this will do
to your computer. You bear all responsibility associated with
installing this..
comments/questions to:
Robert J Miskines
V127P9XG @ UBVMSA.CC.EDU.BUFFALO