Hello gang!
THis is a topic near and dear to my heart, and like Marv, I have probably built a thousand boxes or more since my inception into this mobile audio world.
I'd like to play the Devil's Advocate here and offer a slightly different way to discuss this thread...
We need to look at subwoofer design per era when we discuss this topic, as the best performance in a given enclosure is primarily affected by the drivers chosen. Drivers of today are what has evolved from the push in the mid '90s to build versatile subwoofers with minimal enclosure size requirements so as to fit in our vehicles easier. With the advent of the kicker solobaric and JL Audio W6 series, "all the bass, half the space" was the new direction the manufacturers began to take. The main way to achieve this is How?
Thats right, build stiffer, heavier cones with meatier suspensions, higher moving mass, and massive motors and FORCE the low notes by lowering your Fs.
Jump forward a few years, to about '99 , and we begin to see the trend toward building these same small-enclosure woofers with huge power handling, but now we begin to add higher excursion capability by increasing Xmax (remember when Ground Zero came out with the fat surrounds???) These subs are monsters and the sealed enclosure requirements were miniscule.
With the exception of a very few modern brands, the vast majority of todays subwoofers are geared toward working in a small enclosure simply because thats the direction marketing decided to go. We have a few "multi-purpose" woofers that claim to work well in ported designs , but these subs are sealed first, ported afterthought subs....certainly NOT like Pro Sound drivers or the drivers of yesteryear.
So, when we build a ported box with most of todays subs, even subs that claim to work well in ported designs, we tend to get what I refer to as "sonic slop", this same "slop" we hear whan using a driver with too low a Qts and too low an Fs in an Infinite-baffle setup. Too much overhang, "boomy" notes with little or no resolution of pitch changes, poor transient response, inaccurate attack and decay, I can go on and on. Simply put, very few of todays drivers are built to excell in a ported enclosure, therefore, pitting a sealed design against a ported design in an all-out battle of the Sound Q enclosures would have to be further differentiated by stating "X driver sealed" vs "y driver ported". I know of NO CAR AUDIO WOOFER that is the best of both...do any of you?
So, lets jump back from the dawn of autosound to about the mid '90s, right before the Solobaric desings. We had woofers that had HUGE enclosure requirements. The sensitivity ratings were enormous (remember subs like the IDW, the Rockford Punch and later Power series, the MTX RFL stuff, yadda yadda), yet the vast majority of these subs shared a common item....what was it?
You guessed it! The cones were LIGHTWEIGHT, usually made of treated paper, surrounds were corrugated cloth or foam, and Xmax was MINIMAL. The Fs of these old subs rarely reached 30Hz, if that. Why?
They were based on home audio and pro sound concert drivers, thats why. High sensitivity, huge ported boxes, very dynamic and exceptionally quick. The transient response ability of these older woofers was simply amazing, and yes, they could play up to 80Hz no problem, and often played much higher.
However, people wanted more and more woofers in their cars, and with a Punch Pro 15 needing 4 cubic feet net to sound right, what did people begin to do? They began to look toward companies like Kicker who built Sealed-box-only woofers and figured out with a sub that takes less airspace, you can cram more into the same car , or have more room for a cleaner install.
Yes I am paraphrasing like a mofo. The point is, this topic, at least for me, should be tell us your favorite sealed woofer and why, then your favorite ported woofer and why. Follow me?
Or maybe whats the absolute best sounding subwoofer you have ever personally heard and what enclosure was it in?
Back to the topic----
IMHO,
I feel that there are a few drivers that are absolutely fantastic in a selaed box for SQ, with proper tonal resolution, attack, transient response, no distortion to speak of, and will play cleanly from subsonic to almost 80Hz.
However,
there are a couple drivers that , when placed in a properly-designed ported box, are equal in some areas and better in others, with only ^maybe^ a slight roll-off of the subsonic stuff more quickly than my reference sealed subs.
Shall we discuss specifics here, or what?
Also, what is with the requirement to play a subwoofer up to 80Hz? If we are discussing customers cars off the street who want a good sounding street system, then this topic is not what I thought it was. If we are discussing the uppermost pinnacle of Sound Q utopia, then I argue that in a properly designed system, the front stage should be the dominant factor, and the subwoofer is simply to reinforce the midbass and bottom octaves, NOT to be the primary source of these notes. STRONG midbass presence in the vehicle will be there with a properly-designed and tuned SQ system, and unless the sub is mounted up front, you should never run a sub above roughly 60Hz.
So, do we need some clarification here as to what is expected of this thread?
Sorry for the rambling, its late, and my brain is toast LOL!