Re: How is the IIgs beep generated?

[Mitchell Spector <mitch2gs@hotmail.com>]

 "Michael J. Mahon" <mjmahon@aol.com> wrote:

>Mitchell Spector wrote:
>> "Michael J. Mahon" <mjmahon@aol.com> wrote:
>> 
>> 
>>>Michael J. Mahon wrote:
>>>
>>>>Mitchell Spector wrote:
>>>>
>>>>
>>>>>    Here's a question, one I've been curious about the past twenty years:
>>>>>Can you reproduce the IIgs "beep" on a stock Apple IIe?
>>>>
>>>>
>>>>It can be played using DAC522, but with 5-bit rather than 8-bit
>>>>precision, so it will be a little "rougher".  Still, it would be
>>>>a nice hack.  ;-)
>>>
>>>Can someone point me to the "bong" sound in the IIgs ROM?
>>>
>>>I'll extract it and try it out on SOUND.EDITOR.
>> 
>> 
>>     Not possible. It isn't a digitized waveform (like, say, the "Apple II!
>> shout in the ROM 3 firmware). In fact it isn't even produced by the 
>> Ensoniq chip.
>> 
>>     It's likely just toggling the speaker, very similar to how the Apple
>> II/+/e/c produce their own "beep" (the IIc+ has a different tone).
>> The IIgs "bonk" sounds very UN-Apple II-ish or IBM PC speaker-ish
>> for that matter, especially once you start playing with the pitch.
>> I wonder how it's produced, is it because of the 2.8 MHz CPU
>> or some extra sound circurity that is not found in the 8-bit Apple II,
>> but not part of the Ensoniq either?
>> 
>>     So the question remains: Can you re-produce the IIgs beep
>> on a stock Apple IIe? (digitizing it doesn't count!) :)
>
>Check out:
>
>http://home.comcast.net/~mjmahon/BONK.SHK
>
>(See my other post in this thread for details.)

    Hmm, tried it on my Apple IIGS a moments ago (would have 
tried it on the Apple IIc I rescued from a recycling center a few
weeks ago, but I just put it into storage with my other Apple II's).

    Well, it's quite similar to the IIGS "bonk" yet not at all the 
same. It still has that very distinctive Apple II speaker sound.
Difficult to describe, but I hear "Bonkzzzzzzt", "Bonkzzzzzt"
rather than a crisp and very defined "Bonk". 

    The more I listen to the GS's bell, the more I'm convinced
it's not something that can be reproduced on an Apple IIe.
Example, set the pitch in the Sound Control Panel to the
highest level. Try listening to it over and over, I've never
in all my years of Apple II gaming, programming and tinkering
heard a sound like that from the speaker (excluding, say, 
digitized audio, though even then it wouldn't be as clear).

Mitchell Spector