This video shows that the generator of Xminilab is good enough for Lo-Fi music synthesis.

I assume the Xprotolab Plain can do the same trick. With its price, it could become competitive on sound DIY market - if it had the missing link between ADC and the generator. The generator has to be controlled by voltage.
Look at this - there is demand for cheap modules:
www.kickstarter.com/projects/2012099678/...modules?ref=category
Even if your modules cannot support visual programming, they would find their customers because of lower price.
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