Sealed vs. Ported Speakers

The only thing that I haven't seen mentioned is that as woofers are used over time, their spec do change. Getting port tuning correct is more critical than the spec's straying a bit for a sealed box. So Sealed boxes tend to stay sounding as designed longer than a ported box.
Tim

IMHO, in the simplest terms:

Ports can offer better value.
Sealed speakers can offer better performance.

I read an article a few years back that said ported speakers have more bass output but roll off quickly where a sealed enclosure goes down a bit lower (with a smoother rolloff) but has a bit less output.

Based on this information I wonder why more companies do not make sealed enclosure speakers (even if they are a bit less efficient) as it seems sealed enclosures would work in more rooms as well.

One other wrinkle:

There are variations on sealed boxes. Those designs which limit internal cabinet volume relative to maximum driver displacement (usually called "acoustic suspension" speakers) damp the driver's movement to a greater degree than those which use a larger volume box relative to max driver displacement (generally "infinite baffle" speakers).

Caveat: As far as I can tell, these terms are used somewhat imprecisely in audio writing, so you've got to be careful about written descriptions. The less damped infinite baffle designs generally sit somewhere between ported designs and acoustic suspension designs in regard to tight bass, but...

Not all ported designs are created equal, either. Some (Merlin and Ref 3a come to mind) sound (to my ear, anyway) like they're more highly damped than others. That makes it even harder to compare/contrast the two approaches.

In the end, I believe that generalizations are often of limited utility when trying to pin specific qualities back to broad design criteria like "ported" vs. "sealed" speakers.

Marty

Not many sealed (acoustic suspension) speakers around nowadays. Maybe because manufacturers want specs to sell, maybe because there's a limited amount of drivers available and suitable for sealed enclosures (higher Q drivers relying on the lower Q of the cabinet). Examples of older speakers that were sealed were Dunlavy, Hales and Infinity/Genesis (except for the dipoles). Looking at those names, you might say it's a failed business approach but that's not the why. NHT is still committed to that design.

Every now and then, I still run across an opinion, even one as experienced and respected as Siegfried Linkwitz, that's derogatory to anything other than dipole or sealed, espescially for subwoofers. Everyone is entitled to an opinion, even husbands on occasion. Some have reasons.

Myself, having just built a pair of DIY speakers, chose sealed because of the transient response, being able to fit twice the number of drivers in the same cabinet volume and some forgiveness in the design. Sure, it gives up some deep bass extension but that's what subwoofers are for. Historically, quickly becoming ancient history, I've generally preferred sealed. Still say quality over quantity but not so arrogant to say they're mutually exclusive. There's always a compromise.

For example, let's say the next project is a sub or two. If I want "fast", I could choose a smaller, lighter 10" but in a sealed box that might have an F3 (-3dB) of 40Hz (hardly my idea of a sub). With a port, transmission line or passive radiator, the same driver can be tuned down to the 20's. Or, you start getting bigger, dropping efficiency, adding servo feedback...

Typical snides about ports include "chuffing", time and phase distortions and "wicked, nasty" driver excursion. Even an old fart has to concede something to modern manufacturing techniques, relatively accurate Thiele/Small parameters and the progress of science, albeit sideways, other ways and otherwise.