A rough emulation of an old school 8 bit drum sample cell with some ideas borrowed from Roger Linn. This MaxForLive devices needs Ableton Live 9.x Suite.
Samples can be truncated at the beginning, facilitated by the zoom (Zoom) function which displays only 10ms of the drum sample, starting from the start point (Start). Samples can be tuned up and down two octaves (Tune). Tuning can be quantised to semitones using the step function (S). Tuning can be continuous or only happen at note start (Q). There is a volume envelope for shortening the decay (Decay), and an anti aliasing filter (HiCut). Since Version 1.7 samples can also be transposed via MIDI notes when trigger is set to (All). In that case, the center note is C3.What makes the specific sound of 8 bit drum computers is the low sample rate, which can be emulated with the (Down) parameter, a value of 2 means at 44.1kHz that the sample rate of the non-detuned drum sample equals 22.05kHz. The higher the (Down) parameter, the lower the sample rate and the more gritty and low-fi the sound will become.
The other important factor is bit resolution. With 8 bit there are only 256 steps for the amplitude value at a given moment. With 16 bit there are 65536 steps!The internal 8 bit process of MicroDrum emulates a logarithmic DAC stage and a 24dB anti aliasing filter, so it sounds as good as it can with 8 bit. Still it produces a lot of potentially nice noise in the higher frequencies.
However, for an acceptable low tom or bass drum this is not perfect. Thus a special filter can dampen the high frequencies above 500 Hz faster than the normal decay rate (Damp). This allows to get low drums with a punchy attack but less noise afterwards. Alternatively, upgrade to (12bit), and the noise is gone.When using a sample for a hi-hat and it is triggered repeatedly, it becomes very obvious that it is static. To overcome this, Roger Linn used a looping hi-hat sample and superimposed only the volume envelope. The loop point was not reset at sample start, so each time you triggered a hi-hat you did hear a slightly different sound. MicroDrum has the same playback feature (Free). It probably only makes sense for static looping sounds.
MicroDrum plays back the drum sample, if the incoming MIDI note matches the Trigger Note. Note Off messages are ignored if trigger mode is set to off and do cut the release of a sample if trigger gate is on (Gate). MicroDrum responds to note velocity. It has a volume (Volume) control and a panning function with random (Pan, Rnd). In (Accent) mode, volume is quantised to two steps, and the difference is defined with the (Accent Level) parameter.Samples are dragged in over the waveform view, clicking on the view triggers the samples. Below the view is the file name, next to it the file's sample rate. (Info) brings you to this page, but you probably figured this out already. Easter Egg: click on the (~) to fill the sample buffer with a sine wave.
Slice Mode: this was part of an earlier version and is long gone. Sometimes features disappear...The sampler is mono of course. This is 1982 and memory and CPU power costs a fortune!
Download MicroDrum Version 1.7, short read me text, demo Live set with some samples: MicroDrum.zip[last update: march 6 2016 see read_me.txt for details].
Support
I will most likely not be able to provide help with programming issues. If you intend to modify the instrument, you have to figure out yourself what goes on. However, comments and bug reports are always welcome.MicroDrum 1.7 has been tested wih Live 9.6 and Max 7.12 on Mac OS 10.8.5 and 10.10.5
LicenseYou can modify this device. You can use it to create the best song ever and sell that song. You cannot sell this device or a modified version of it. You cannot copy code from it to use it in other commercial devices or software packages.
Enjoy! Robert Henke, December 29 2014.