Hi,
(I have posted a similar message in general discussion before finding this thread)
I am BSC from Cologne in Germany and used to be a coder and musician on the Amstrad CPC in the late
80s and 90s. I have also written a tracker which was quite popular in the olden times called Soundtrakker.
A few years ago I got interested in the SID effect known from the Atari ST which I believed to be impossible
on the CPC until I saw a demo called "eklhaft" or so on the Spectrum. I started experimenting and came up
with some kind of SID player/tracker called "AYAY Kaeppttn" which is also on github:
https://github.com/BetaSoftCologne/AYAY
Last summer I got interested in this topic again and wrote another engine which mixes 3 virtual SID
voices into one, emulating some of the most common wave forms of the SID, which I am still working on.
There are some previews on soundcloud:
https://soundcloud.com/carl-carbunckel/tracks
Then, a few days ago, I learnt about an engine originally wrote for the Enterprise, first ported to the Speccy,
then the CPC which sounds absolutely awesome and apparently does some of the things better than I did.
BUT: My solution is less memory hungry (which is somewhat important to me as I would like to release
something at a demoparty based on this), so I am currently thinking about different options like cooperation
and such. It does probably not belong here but I am a bit frustrated to have found this other engine and
this some of my momentum for the project is gone.. Maybe that's why I am (also) here.. Looking for feedback,
new ideas, maybe some cooperation towards a production, positive energy in general 
Anyway, I am looking forward to interesting discussions with you guys!