| the simple truth is that there is no tonal difference inherent in the plavement of the ports. However, the size, length, number, and tuning of these ports does in fact affect tone, as well as whether or not there are ports. Having ports on the back however means that you can't place your cabinet with its back right up against a wall - you'll have to leave a couple inches for the port to "breathe".
Other than that though, there is no tonal difference in where the ports are placed.
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#Big Macintosh of the brony bassist club.
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