Which books OR online courses are best for Audio Industry


Pl. recommend books you feel must for Loudspeaker design building Amplifier. Also about online couses for the same. here are many on acoustics but very few on Amp & loudspeakers.
ashoka
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Loudspeaker Design Cookbook by Vance Dickason
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Testing Loudspeakers Book by Joseph D'Appolito
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both available at Parts Express
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