Drum engine midi mapping unstable?

MIDIbox SID
1

Hi all.

I’m finally giving my sammich 6581 the time it deserves. . . but it’s behaving oddly.

When I play the drum sounds over a midi keyboard the mapping jumps around. For instance, a bass drum will be on C#1, but after I play a few more keys it either disappears completely or gets replaced by another sound. The mapping also has several dead zones on the keyboard where a group of 6 or 7 keys in a row don’t trigger the Sid.

Is this some weird note stealing thing that’s normal or is this a more serious problem? Thanks!

2

When I play the drum sounds over a midi keyboard the mapping jumps around. For instance, a bass drum will be on C#1, but after I play a few more keys it either disappears completely or gets replaced by another sound.

Yes, this is related to the dynamic voice allocation, as drum sounds have to share 6 oscillators, see also http://www.ucapps.de/midibox_sid_manual_d.html

If a drum instrument is played very often (like bass drum), it could also be assigned to a dedicated oscillator.

It’s even possible to assign multiple instruments to the same oscillator, just for the case that they alternate anyhow (e.g. hi hats)

(this also makes sense if a voice is routed through the filter)

The mapping also has several dead zones on the keyboard where a group of 6 or 7 keys in a row don’t trigger the Sid.

Yes, there are 16 instruments mapped to two octaves (=24 keys).

The remaining 8 keys are not mapped (initially I wanted to avoid confusion…)

Best Regards, Thorsten.

3

Got it. Thanks for such a speedy and thorough answer TK! I’ll try the dedicated oscillators method tonight.