Could a question that regards to music software or sequencers be treated as appropriate?
Like 'How to make this and that in Reason 4'?
Synthesizers and sequencers are just a type of musical instruments, and is without a doubt a form of musical "practice & performance, composition, technique, theory, and history."
As such it is without a shadow of a doubt on topic with the current definition of topics. The only way it could not be is if we add a "unless you use a computer" at the end. :-)
I think you're looking for the Audio Recording and Production site.
For instance, their FAQ has some of these topics:
- audio editing, mixing, and mastering
- signal processing
- audio post-production
- audio-related media and file formats
- installation, configuration, and operation of software related to these topics
Though, I could be wrong in over looking something, and although someone might be able to read more specific detail into what you mean, given the information provided I certainly can't and can only say, no.