What effect does a well-flamed maple back on the sound? Must all good violins have well-flamed maple backs?

Tonally it does not need to be well flamed. It looks nice and the wood is more expensive. If you are building a good instrument you probably want it to be aesthetcally pleasing in addition to sounding good. Hence most luthiers use "well flamed" maple for the back and neck.

The reason I ask this is that I've come across China made violins (of brands which are not well known overseas) that use well-flamed maple backs (not printed on ones). But they costs less than US150. I wonder if they are good? Maybe I should put it another way - are all violins that use well-flamed maple defintely good violins?
Assuming you dont get to try out the sound of the violin before buying, would you go for a violin described above (unknown Chinese brand using well-flamed maple back), or a brand that is better known internationally but uses only slightly flamed maple back?

Painted flaming is uncommon now, as is pressed plywood.

The wholesaler's markup on Chinese violins is HUGE - much bigger than the normal retailer markup. Hence someone who imports direct from China can give a much better price for a comparable instrument. Beyond that observation, it's hard to tell just by looking.

Liz

There is nothing, absolutely nothing, intrinsically valuable about a flamed piece of maple versus an unflamed piece. The difference in value is strictly a matter of appearance.

And the difference, at a wholesale level, between a log that is flamed versus one that is not, is non-existent. Until you cut a log, you don't know what it looks like.

The prevalence of flaming is a clever way to make things look like high quality. But flaming in and of itself has nothing to do with quality. It is not part of the process, and its presence has no effect on the spectral qualities of the wood.

Ah ha! So now I know... Actually, I don't really find the "flamed" maple backs particularly attractive.