Electric guitar counted as digital?
Well, analog recording is basically electricity and magnetism so an electric guitar is perfectly fine. I guess I should have clarified all the finer points of defining a "purist". Well, I even seem to brake my own rules 'cause I do carry over my finished tracks to CD but everything prior to that is totally in the analogue domain. I still define this as being a purist.
I would like to clarify, however, that this is not an exclusively analogue vs digital sorta thing, as "purist" also means, to me, using very little to achieve the end product, which means a minimalist approach to recording, less of everything, including mics and out-board gear, even if it's analogue in nature.
Picture one microphone a said distance away from the piano, another near a guitar / guitar amp, another one or max two mic'ing a drum set, one for backing vocals, another for main vocal etc...... all running straight into a recorder / mixer combo [EQ may not even be allowed] and if a compressor is used, it is done on the way in, with very gentle peak limiting at most. Same thing for tape delay and only to taste. More often, though, natural room sound is solely used.
Basically, your choice of mics, placement of them and room, almost totally dictates the end sound.
The majority of the time is used to choose mics and precisely setup these mics and their levels. The actual recording is accomplished in one live take or overdubbing, if a one man band. Still, under my rules, that's being a purist.