|
Speaker Asylum General speaker questions for audio and home theater. |
|
|
|
Speaker Asylum General speaker questions for audio and home theater. |
|
In Reply to: RE: Rear port pros and cons (not an unbiased opinion) posted by theaudiohobby on November 18, 2007 at 15:18:07:
Port adjustability is one issue, and might be a nice option to have regardless of where the port is (though a potential issues arises with a front-facing adjustable port; see below). I will concede your point that port length is not infinitely adjustable, but if you have access to a modelling program you can see how much variation in bass response is attained by changing the port length within reasonable finite limits set by the enclosure's dimensions. Offhand I can think of only one manufacturer besides myself who offers adjustable-length ports, but I'm sure there are others.
Port placement is a different issue. In my opinion either rear-firing or down-firing is usually preferable to front-firing. Apparently mine is a minority position, judging from a glance at the marketplace.
Port adjustability is not an advantage unique to rear-firing ports. In my opinion flexibility is maximized when the adjustable port is rear-firing; most of my reasons for this have already been stated but here is another:
Sometimes the room offers too much bass reinforcement, and with a rear-firing port you can reduce the boundary reinforcement by moving the speaker away from the walls. With a down-firing port, you'll still be getting a lot of boundary reinforcement from the floor wherever you place the speakers. So if the goal is maximum adaptability through a combination of speaker placement and port tuning adjustment, I think that rear-firing offers a wider range of flexibility than down-firing.
One factor that I haven't mentioned yet is the damping material inside of a reflex enclosure. For maximum bass you want no damping material, but to minimize midrange coloration through the port you want some damping material. The amount of damping material you need to acceptably minimize midrange coloration is greater with a front-firing port than with a down-firing or rear-firing port. This translates into more powerful low bass from either of these less-conventional formats because of the reduced damping material requirement.
Note that increasing the port length also increases the damping material required to keep midrange coloration acceptably low. So this is another reason why an adjustable port makes more sense on the bottom or rear of the speaker, as less damping material is required with these configurations.
Yes there are excellent speakers with front-firing ports, and probably some lousy ones with rear-firing ports. It's not the biggest issue in loudspeaker design.
Duke
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- RE: Rear port pros and cons (not an unbiased opinion) - Duke 16:57:35 11/18/07 (1)
- RE: Rear port pros and cons (not an unbiased opinion) - Cruz123 20:37:40 11/19/07 (0)
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2024, Audio Asylum, all rights reserved ]
