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yes, the ports are in front, hiding behind the speaker grille, so people commonly refer to it erringly as a CB cabinet. here's a pic that I posted a while back, it's still in my attachments folder:
it's got 5 little ports, and those ports aren't big enough to fully vent the compressive force of the drivers on the cabinet air, so the ports tend to pump/whistle on large signals.
regarding the Infinite Baffle thing -- the term gets misused a lot and i'm guilty in that regard. ideally, a LF driver can be mounted on a rigid flat panel that's infinitely large with infinite space behind it, what engineers like to call a "half-space" mounting configuration. The ideally large baffle separates the front and rear soundwaves from combining to comb-filter the LF response of the cabinet. All open back speakers attempt to achieve this sort of arrangement, though none of them really pull it off, because everyone tries to trade away panel size for convenience, and they get all of the problems that go along with that compromise. To make the anti-combing effect work the panel dimensions need to approach the wavelength of the sound being produced. That tends to become more possible with a distorted guitar signal as the power spectrum is focused more on MF/HF content and bass tones get rolled away. Suffice it to say that that Mojo cab isn't ideal, but it's still one hell of a lot better than a Deluxe cabinet. It's easy to hear the difference that a larger baffle size makes.
People commonly refer to large closed back cabs as an approximation of an infinite baffle. technically, for that to apply the box has to be large enough that the compliance of the volume of air in the box would greatly exceed the compliance of the speaker's suspension (Vas in Thiele-Small terms). Not many MI applications satisfy those conditions -- everyone likes to design speaker boxes to have the smallest possible baffles to accommodate the radius of the driver for mounting. Nobody wants' to make boxes as big as they really need to be.
it's got 5 little ports, and those ports aren't big enough to fully vent the compressive force of the drivers on the cabinet air, so the ports tend to pump/whistle on large signals.
regarding the Infinite Baffle thing -- the term gets misused a lot and i'm guilty in that regard. ideally, a LF driver can be mounted on a rigid flat panel that's infinitely large with infinite space behind it, what engineers like to call a "half-space" mounting configuration. The ideally large baffle separates the front and rear soundwaves from combining to comb-filter the LF response of the cabinet. All open back speakers attempt to achieve this sort of arrangement, though none of them really pull it off, because everyone tries to trade away panel size for convenience, and they get all of the problems that go along with that compromise. To make the anti-combing effect work the panel dimensions need to approach the wavelength of the sound being produced. That tends to become more possible with a distorted guitar signal as the power spectrum is focused more on MF/HF content and bass tones get rolled away. Suffice it to say that that Mojo cab isn't ideal, but it's still one hell of a lot better than a Deluxe cabinet. It's easy to hear the difference that a larger baffle size makes.
People commonly refer to large closed back cabs as an approximation of an infinite baffle. technically, for that to apply the box has to be large enough that the compliance of the volume of air in the box would greatly exceed the compliance of the speaker's suspension (Vas in Thiele-Small terms). Not many MI applications satisfy those conditions -- everyone likes to design speaker boxes to have the smallest possible baffles to accommodate the radius of the driver for mounting. Nobody wants' to make boxes as big as they really need to be.
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