AUDYA4 dimensions are 21"x14"x5"
i'm currently using: (as i'm trying to keep weight down)
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16"x22"x5"
thinking about getting, for a bit more protection: (but it's a bit bigger), this pic is of the 10"x15", but same case
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19"x21"6"
neither of these is a perfect fit, as they are 2"-5" over on the depth
what are you guys using for your AUDYA4?