Re: Release of DMS Drummer: A Percussion Sequencer for the Apple II

[Michael J. Mahon <mjmahon@aol.com>]

Michael J. Mahon <mjmahon@aol.com> wrote:
> "Michael J. Mahon" <mjmahon@aol.com> wrote:
>> With inspiration and musical mentoring provided by Seth Sternberger
>> of _8-Bit Weapon_, I've impemented a percussion sequencer/synthesizer
>> for the Apple II.
>> 
>> It allows a user to create sequences as long as 255 patterns, where
>> each pattern is one of a set of 16 musical measures. Within each of
>> these patterns, any one of 8 percussive voices can be played at any
>> 1/16th note boundary.  In addition, the "pitch" for playing back the
>> percussion sample can be specified, which is useful for pitched drums,
>> like tom-toms.
>> 
>> Like RT.SYNTH (which Seth also offers as DMS Synthesizer) DMS Drummer
>> uses the DAC522 5-bit 22kHz pulse-width-modulation wavetable synthesizer
>> engine, driven by a sequencer that runs in real time.  DAC522 represents
>> "silence" as pairs of 6 cycle pulses spaced 46 cycles apart, regardless
>> of whatever the code is doing--which subroutine it's calling or which
>> branch path it's taking.  Executing "branchy" code while maintaining
>> a constant stream of evenly spaced pulses is pretty tricky, but it must
>> be done if the sequencer is to keep silent except for the desired
>> sounds.
>> 
>> Seth is offering the full version on his website:
>>    http://www.8bitweapon.com/store.htm
>> for $15, but the demo version (downloadable both from my website
>> and his) is free for you to play with!  It is limited to 8 distinct
>> programmable patterns and the Save function is disabled.
>> 
>> Listen to the sample song, created by Seth, on either of our websites
>> to hear the realistic rhythm line that an 8-bit Apple II can produce!
>> The melody and bass lines are being played on RT.SYNTH, so the only
>> non-Apple II-produced sounds are the "explosions" (which could also
>> have been played by SOUND.EDITOR on an Apple II!).
>> 
>> -michael
>> 
>> DMS Drummer for more rhythmic Apple II computing!
>> Home page:  http://home.comcast.net/~mjmahon/
>> 
>> "The wastebasket is our most important design
>> tool--and it's seriously underused."
> 
> I should mention that many emulators do a pretty bad emulation of Apple
> sound at 22kHz--I recommend a real Apple II, but with a good amplifier
> attached. The "treble" should be turned down, since any frequencies above
> 5kHz are just noise. 
> 
> Headphones are also good, unless you are one of the people who can hear
> 22kHz. ;-)

One more thing--DMS Drummer has a 
command to "flip" the sound output between speaker and cassette output.
Although the cassette output is at microphone level, it is often more
convenient to connect to an external amplifier. 

-michael - NadaNet 3.1 and AppleCrate II: http://home.comcast.net/~mjmahon