[quote name='BigRedX' timestamp='1407247281' post='2518719']
Why are you asking us? Surely that's a part of what you are paying your luthier for - to advise you on the best way to get the sound, feel and look that you are after.
IMO if your luthier isn't doing this for you, then you have the wrong one.
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Its more than just a luthier, its also what kind of wood they have in stock.
My Spectors are also growly but because they use soft maple. The maple that Jon Shuker uses is too stiff to be growly without a healthy dose of wenge. The maple is almost like graphite. Dood's headless 6 sounds nice and growly though. Martin Petersen makes some amazing wenge and maple necks. Urb's bass has exactly the kind of growl I've been looking for. The Yamaha BBNEII Is also very growly but has a 5 piece maple and mahogany through neck and alder wings. Old Musicman Stingrays are super growly and some of the SR5s from the late 80's and early 90's are very growly too - maple neck and ash body.
Each bass is its own recipe and has its own flavour of growl. The Yamaha is very soft and purry, the Spectors are a little barky and the stingray has an aggressive snarl.