Sealed vs. ported enclosure midwoofer SQ!

I suspect this topic is covered dozens of times, but I couldn't find the answer I'm looking for.

So I have a speaker design that, in any case, woofers will be crossed to a horn around 800 Hz. This is constant. I'm either gonna use a single Faital 12RS430 in a 70L ported box and have decent F3 and 800 Hz covered, or I will use a woofer like Fostex FW 305 in a sealed box and use a second woofer starting from 100 Hz to the low end.

My question is about the quality of this 100-800 Hz. Which one might sound better? More resolution. The goal is not higher SPL, just more mid/low-mid clarity. Using a low Mms midwoofer vs. a heavier woofer (although Faital's Bl/√RE is higher...). If you have any woofer suggestions that can beat the FW305 in an even smaller box, please don't hesitate.


Thanks for the answers in advance!
 
Either way, for the purposes of clarity and detail…..you’re compromised by your choice of crossover point……most fundamentals and 1st harmonics in music are in the 500- 1000hz range. By placing the crossover there, you’ve now introduced phase interference…….something I’ve never really understood people doing after spending tons of $$$ on drivers with low distortion

Midrange is midrange where hifi is concerned…..3 octaves maximum coverage from a single driver based on complex music. 500hz to 3khz is a MUCH better solution when the goal is clarity and detail. A quality 6-6.5” pro midrange driver can do this easily.
 
Thanks @DualTriode

But will there be audible SQ difference with these 2 speakers, when listening music around 80 dB? (< 90 dB at speaker)

I know technically it looks better, but will it differ subjectively?

Your speakers your ears, you tell us.

As you turn up the SPL Force Factor modulation becomes a bigger player. IMD increases and becomes more irritating, much more so than Harmonic Distortion.
 
Your speakers your ears, you tell us.
I would really build both speakers if I had time. I'll think about it. @mayhem13 's comment is also valuable. But I think I can't do anything about it unless I go extreme. Can't lower the xover point with the horn I chose. I wouldn't want any woofer to play higher either, even if I do 3-way (sealed mid that I wrote above), the 1-2 kHz region is also important. 800 Hz looks like a good compromise. (maybe not! 😀)
 
You want to cross where the woofer and your waveguides disperion matches..
More important then the exact xo frequency.
Also 1khz is not the worst place nessecearily, your ears have problems with localization in that range.

Sealed is easier to implement.
Better for integration with a sub.
What you loose is efficiency. midrange leakage through port and possible chuffing etc. Are things thats avoided.

Trade offs either way
 
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Trade offs either way
That’s good to hear!

I still think sealed bass/mid envelope might be easier to manage in an untreated room. But I don’t know if it’s worth the extra effort (and more volume…)

What is the best 12 inch woofer to use below 100 Hz, in a sealed box. Even hitting 40 Hz is enough. Just trying to see what might be the minimum volume and box size for subwoofer + midwoofer + horn setup. I guess it’s around 100 L.
 
I admit it’s better to lower the xover point, but I can’t do that with the current horn. So is it better to have it after 1kHz? Where we are more sensitive 🤔

(2-3kHz, even more so…)

Everything is a compromise of course…..but there’s some silliness in what defines a compromise as well as some well grounded strategies….

Some things to remember…..there is no perfect speaker nor are there any reference recordings……subjectivity is a biological boundary worthy of respect.

Measurements will give you some insights…..but how a driver behaves with complex music is impossible to map. This is where voicing and practical experience come in to play along with some basic acoustic principles.

Source content/recordings inconsistency brought rise to the ubiquitous bookshelf two way where if properly done, EVERY recording sounds good……..but because of the inherent compromise of the crossover point, very few recordings sound exceptional.

If you want to take the path to foundational perfection……a single driver without distortion or phase overlap from 500hz to 3k is a great place to start.
 
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Use sealed for the mid-woofer, then you can increase the enclosure volume to hit a Qtc below 0.5, giving more control...a critical thing considering the frequencies we are sensitive to..


------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Rick...
 
Thanks @DualTriode

But will there be audible SQ difference with these 2 speakers, when listening music around 80 dB? (< 90 dB at speaker)

I know technically it looks better, but will it differ subjectively?
A pair of sealed 12" at 4 meters can do ~80dB at 30Hz with only 1.7mm excursion with no room gain.
Screen Shot 2025-06-14 at 5.56.44 PM.png

Porting could cut that low excursion level in half.
The Faital 12RS430 is rated for 13.57mm Xmax, should have very little IMD or AMD at such low excursion, I'd expect they would be clean to near 10mm, ~107dB at 1m.

I'm all for three-way if the SPL demands it for clarity, but at 80dB it's not required, two-way should work fine.

Art