My first prototype speakers were front-ported, but I switched to rear-ported. Here's why:
1) If unwanted midrange energy emerges from the ports, it will be farthest possible from the listener, and thus less likely to be audible.
2) It is desirable to spread out the low-frequency sources as much as is feasible in as many dimensions as possible. With a rear-facing port that's at a different height from the woofer cone, once the speaker is toed-in, the two low-frequency sources (woofer and port) are at a different distance from the room boundaries in all three dimensions.
3) If port-plugging is an option, we have less visual disturbance if the port is on the back.
4) If a rear-facing port is tuned with boundary reinforcement in mind, there is no detriment from its being on the rear of the cabinet. Audio Note proved this; my imitation of their approach is sincere flattery.
I recall one time delivering a pair of rear-ported speakers to a customer. They replaced a pair of well-respected front-ported transmission line speakers. One of the first things the new owner commented on was that the in-room bass was smoother. I think this is because, with the speakers toed-in as recommended, the room-mode-smoothing effect of staggering the bass sources in all three dimensions had enough of an influence to be audible.
Duke
1) If unwanted midrange energy emerges from the ports, it will be farthest possible from the listener, and thus less likely to be audible.
2) It is desirable to spread out the low-frequency sources as much as is feasible in as many dimensions as possible. With a rear-facing port that's at a different height from the woofer cone, once the speaker is toed-in, the two low-frequency sources (woofer and port) are at a different distance from the room boundaries in all three dimensions.
3) If port-plugging is an option, we have less visual disturbance if the port is on the back.
4) If a rear-facing port is tuned with boundary reinforcement in mind, there is no detriment from its being on the rear of the cabinet. Audio Note proved this; my imitation of their approach is sincere flattery.
I recall one time delivering a pair of rear-ported speakers to a customer. They replaced a pair of well-respected front-ported transmission line speakers. One of the first things the new owner commented on was that the in-room bass was smoother. I think this is because, with the speakers toed-in as recommended, the room-mode-smoothing effect of staggering the bass sources in all three dimensions had enough of an influence to be audible.
Duke