#1
Hi i'm just curious , what's the differences between rosewood , maple , mahagony, etc ?
Can you tell the wood by just looking the guitar ?
#2
Just by looking you say? Not if the wood's covered in paint (with the exception of bookmatched guitars of course)

Ebony, maple and rosewood are the most common woods for fretboards and they're all quite easy to recognize. They all have their tonal qualities, but playability-wise it's probably more important whether the fingerboard has been polished and stuff

The same goes for neck and body woods: some types of wood are just more suited for certain specific purposes like strength, weight, resonance, etc. up to the point where guitar manufacturers even tend to combine certain woods for the bodies of solid tops: a Gibson Les Paul for example typically combines a mahogany body with a maple top (LP Studios excluded)

In the end the choice of woods probably isn't as important as, say, the type of pickups -> any experienced player can tell a Telecaster apart from an ESP just by listening to a recording, but I doubt there's many people who can instantly tell you whether the manufacturer decided to use an unconventional wood type for those instruments. It certainly makes a difference but sadly the selection and employment of grade A quality tonewoods is probably the most expensive thing factor in the manufacturing process of an awesome guitar (after manual labor, that is)

It's a slightly different story with acoustic guitars tho: they don't have pickups which instantly makes the selection of tone woods one of the most important element in shaping the guitar's sound (don't underestimate other factors like string types and body shapes tho...)

If you want some info on why people prefer certain wood types just google about...

http://www.jemsite.com/jem/wood.htm

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