On 19 Nov 2001, at 23:44, John H. Miller wrote:

> I have an old calendar program (Delrina Daily Planner) that I like
> very much and I would like to keep using.  It uses the PC Speaker
> to play different sounds as alarms for upcoming events.  I would
> like to route the PC Speaker alarms through my Sound Card instead.
> I am thinking about just clipping my PC Speaker and running the
> wires over to an open input on the sound card but I thought I would
> check and see if anyone is aware of a software program or driver
> that would allow me to play PC Speaker sounds through my Sound Card
> (without having to buy a new sound card)?  If not, I will just cut
> the speaker wires and run it physically to my sound card?
>
> Thanks for your help,
> John H. Miller

  I cannot recommend that you do this, for two reasons:

1.  The motherboard signal to the speaker is a square wave, already
amplified to sufficient levels to drive the speaker cone back and
forth.  It would not surprise me if these current levels greatly
exceed anything the electronic components on your sound card expect
to receive as inputs.  I would count it as lucky if only the sound
card is damaged.

2.  There was an era, just before Windows really caught on, when some
bright programmers figured out how to get better-than-square-wave
sound qualify from the PC speaker by sending it very high frequency
signals -- signals too high to hear directly and too fast for the
physical speaker to reproduce in any case -- which drove the speaker
to "shape" a more natural waveform than the raw square-wave hardware
was designed for.  An application using this technique -- and since
the next step was to rely on sound cards and OS drivers, your Delrina
app may qualify -- requires the physical dynamics of the PC speaker
to make intelligible sounds, and cannot be correctly processed by a
sound card.

  All that said, no cutting of wires should be necessary.  On every
system I've ever seen, the speaker connection to the motherboard was
a standard .10" connector (usually 4-pin although some early ones
were 2-pin).  Disconnecting the speaker to expose the pins on the
motherboard should just be a matter of sliding the connector off
those pins, and if you can't cannibalize a front-panel LED cable from
an old case to fit, you can buy a CD-ROM-drive-to-soundcard cable for
about $3 with the right kind of connector on it.
  Short of burning out your sound card (see #1 above), you can at
least minimize the physical damage done to your system to test this
arrangement....

Dave Gillett

                         PCBUILD's List Owners:
                      Bob Wright<[log in to unmask]>
                       Drew Dunn<[log in to unmask]>