Today I read about a "2.5-way" speaker from the Canadian PSB (http://www.psbspeakers.com) that uses two identical woofers, but each woofer is in an enclosure of different size and tuning. I read that the PSB system has bass out of both midbasses, but only midrange out of one. So naturally, my curiosity is piqued.
Then Paradigm, another Canadian brand, once had a subwoofer in their Legend tower, but in their new Legend v.3 (its successor), three identical woofers are used. One of these goes in a sealed upper enclosure, while the other two are in a large ported enclosure in the same tower.
The Bose (I know how much you all hate hearing about them) 701s use the reflecting midrange driver in its own separate enclosure, but I don't know if it's ported or not, and the 8" bass driver is in the voigt pipe.
So why is everybody doing this? On the PSB site, I read something about purity of the midrange.
Then Paradigm, another Canadian brand, once had a subwoofer in their Legend tower, but in their new Legend v.3 (its successor), three identical woofers are used. One of these goes in a sealed upper enclosure, while the other two are in a large ported enclosure in the same tower.
The Bose (I know how much you all hate hearing about them) 701s use the reflecting midrange driver in its own separate enclosure, but I don't know if it's ported or not, and the 8" bass driver is in the voigt pipe.
So why is everybody doing this? On the PSB site, I read something about purity of the midrange.
BAM said:
The purpose of a 2.5-way speaker is to compensate for the Baffle Step phenomenom. The 2nd woofer is XOed in at about the Baffle Step frequency.
The purity of the midrange comment comes from having a single driver covering the midrange as opposed to 2 in an MTM.
The 1st 2.5 way i ran across was John Greenbank's Tangent RS6, but i suspect there are others pre-dating this (late '70s).
dave
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.