[comp.sys.apple] APPLE IIGS SPEAKER OUTPUT

aehl@csd4.milw.wisc.edu (Donald J Aehl) (11/15/87)

Could anyone explain to me why I am not able to record the sound from
an Apple IIgs speaker output with just a ordinary tape recorder and a
stereo patch-cable?

I have tried this a few times with both Music Construction Set and with
The Music Studio and neither allows me to record the sound (music) with
any clarity.  When I play the sound back it is accompanied with a lot of
static and noise in the background.

I have heard that if you connect the sound output to the input of a stereo
reciever and then into a cassette deck, the music can be clearly recorded.
Why can't I do it with a normal stereo tape recorder (I don't own a stereo
reciever).  Does this problem have something to do with amplification?
My feeling is that it does but I really don'y know much about sound 
elecxtronics.

Any help or explanations would be greatly appreciated.

(no I don't own MDideas' stereo card)

TMURPHY@WPI.BITNET (11/17/87)

The problem with recording is probably the impedance of the outputs/inputs
used.  I don't know what the GS has, but if it's a speaker connection it's
probably 8 ohms, while a microphone input would be a few thousand ohms.
In other words, they don't like each other.  A standard audio input (line
level) should work, otherwise try a phono level input.

Chris Murphy
Worcester Polytechnic Institute
Bitnet:  TMURPHY@WPI
Arpanet: tmurphy%wpi.bitnet@talcott.harvard.edu

kamath@reed.UUCP (Sean Kamath) (11/28/87)

In article <8711170209.AA02996@wpi> TMURPHY@WPI.BITNET writes:
>
>The problem with recording is probably the impedance of the outputs/inputs
>used.  I don't know what the GS has, but if it's a speaker connection it's
>probably 8 ohms, while a microphone input would be a few thousand ohms.
>In other words, they don't like each other.  A standard audio input (line
>level) should work, otherwise try a phono level input.
>
>Chris Murphy
>Worcester Polytechnic Institute
>Bitnet:  TMURPHY@WPI
>Arpanet: tmurphy%wpi.bitnet@talcott.harvard.edu

And the propable answer to this problem is to take a 10 ohm resister and
short the leads, while it's hooked up to the microphone, to give it a ~8
ohm impedance.  However, the question is, how many watts is the output
power?  . . .

I think I'd use a bigger resister, but. . .

Sean




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