Average time is 200 – 300 hours from start to finish.
The traditional recipe is maple for back, sides, and neck. Spuce for the belly.
The reason being that violins actually work similarly to a drum – with the soft flexible drum skin making the sound and the drum body reflecting the sound out to our ears. Violins have a flexible soft wood spruce belly (the top) which produces most of the sound, and the hardwood maple back and sides reflect the sound out to our ears.
They’re physically exactly the same, the difference is all in the setup. Violins are mainly setup for classical players, usually with sweet sounding nylon/perlon strings, and with standardised string spacings, string heights, and bridge radius. Fiddles are mainly setup for ‘fiddlers’ or fast players, usually with the brighter sounding steel strings, a lower string height, and a flatter bridge to help with fast string crossing.