I installed one on my Ibanez AEB5. Definitely a difference in sound. Compared to the one I have with no OPort installed, it is a much fuller and punchier sound, with more low-end dynamic.
It doesn't make it so loud that it will compete with an URB, but it definitely improves the presence and evenness of the tone on an ABG.
One wonders what would happen if they actually created an OPort with the cubic volume of your average ABG in mind.
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