I’m trying to understand woofer specs to choose a suitable woofer, it feels very confusing with all the parameters effecting each other.
My fixed variables are large sealed cabinet (200-280 Liters) 2 15” woofers in a MEH design built around the Klipsch large K402 horn, and only need woofers to go up to 600 hz.
Looking for lots of articulation and subtlety, not for ultimate low end extension.
I’m trying to understand the relationships between qts, cone mass, bl, xmas, etc.
Any perspective on how to choose a suitable woofer would be appreciated. Thank you
My fixed variables are large sealed cabinet (200-280 Liters) 2 15” woofers in a MEH design built around the Klipsch large K402 horn, and only need woofers to go up to 600 hz.
Looking for lots of articulation and subtlety, not for ultimate low end extension.
I’m trying to understand the relationships between qts, cone mass, bl, xmas, etc.
Any perspective on how to choose a suitable woofer would be appreciated. Thank you
I should add that this is a DSP controlled speaker, so perhaps a flat FR is not that important, as I have the ability flatten the fr to some degree.
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Curious why "sealed" is a fixed variable? Seems like with 280 liters shared between two 15" woofers you should definitely leave the option open for a ported cabinet, especially from a 15" playing up to 600 Hz.
He mentioned he wasn't looking for lower extension, he was looking for clarity.
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I am under the impression that sealed has a tendency towards greater “transient speed/recovery” to have a greater sense of articulation. Also, ported seems to add a whole new layer of complexity, port size, length, etc…
I would say this depends on the woofer you choose. I've heard some horn loaded 15" paper cone woofers that were very articulate. With DSP you have a lot of options, but in my opinion I wouldn't leave out the option for ported. I think sealed vs ported will depend more on the woofer of choice. I know you aren't necessarily going for a low f3 with these, but you might find that you aren't necessarily sacrificing slam and attack by using a ported cabinet. Not trying to correct anyone here, just my opinion.
Also port length is fairly simple to figure out using some of the free software out there (like WinISD for example).
Also port length is fairly simple to figure out using some of the free software out there (like WinISD for example).
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I do think ported certainly has advantages, I believe lowering the extension seems to be chief among them, and allowing a smaller box to go deeper. Due to the size of my horn, the box will end up at approximately 280L. I can fill the inside to reduce volume as part of a “tuning” process, but I thought having a large volume might give me more flexibility than a small box.
So basically I’m just asking people with more knowledge and experience, how do I choose a woofer, given it’s going in a up to 290L box, needs to crossover at 5-600hz, will be used with DSP, and very articulate sound if favored over maximum bass extension.
I’m hoping with these 4 factors in place there may be some set of specs that are more likely to achieve my goal than other specs.
And also, my budget could got to 500$ per driver.
Thanks for any perspective
So basically I’m just asking people with more knowledge and experience, how do I choose a woofer, given it’s going in a up to 290L box, needs to crossover at 5-600hz, will be used with DSP, and very articulate sound if favored over maximum bass extension.
I’m hoping with these 4 factors in place there may be some set of specs that are more likely to achieve my goal than other specs.
And also, my budget could got to 500$ per driver.
Thanks for any perspective
Hmm, so wanting a BP4 alignment, i.e. loading into the horn or just in the same sealed box as the MEH?
Assuming the latter, then easiest to use a sealed box calculator to find an affordable driver that's 'close enough' via iteration working backwards using driver Vas: (2*Vas)/280 L = 'a' to find Qts, then Fs to find Fc, F3.
T/S theory explained if you prefer to 'do the math' 😉
Assuming the latter, then easiest to use a sealed box calculator to find an affordable driver that's 'close enough' via iteration working backwards using driver Vas: (2*Vas)/280 L = 'a' to find Qts, then Fs to find Fc, F3.
T/S theory explained if you prefer to 'do the math' 😉
Still on the hunt for a woofer. Comparing Fiatal 15pr400 and AE 15tdm. Both have a lot of very similar ts parameters. I’m trying to understand what else to look for. Still looking for mid bass articulation, say 50 -500hz. Someone said, “you can always add subs, but the mid bass is what it is.”
FWIW most 15" woofers are intended for professional, not home use. As such they typically do not have T/S parameters that lend themselves to any meaningful bass extension in a sealed enclosure. I would suggest getting a copy of WinISD. It's free and works well for simple enclosures. It has a great many drivers in its data base and you can also enter new drivers and their T/S parameters. It is easy to model various drivers in different enclosures to see how their T/S parameters affect response. I think doing this would be a good educational exercise. BTW, what is the intended use? I'm not sure I understand the logic of using two 15" drivers in a sealed enclosure for home use.
In my experience, you look for something that has a good midrange response (flat response, flat dispertion off axis) but still can go low enough (FS) sealed (so low EBP and high QTS) and give signal on low power (so mms not to high or BL to low).
Best i can think of should is the SB42FHCL75-6. With a higher order crossover (at least 2nd order preferable higher) at 600 it should work well in a 280L for two drivers, and it can go low sealed like that. F6 would be 30Hz in my sims, and that until 107dB without running out of xmax. But i don't know them all off course...
Best i can think of should is the SB42FHCL75-6. With a higher order crossover (at least 2nd order preferable higher) at 600 it should work well in a 280L for two drivers, and it can go low sealed like that. F6 would be 30Hz in my sims, and that until 107dB without running out of xmax. But i don't know them all off course...
Ideally you want an upper mass corner (Fhm) to cover the BW, so assuming 20 Hz Fs:
Qts' = 2*20/500 = 0.08, so all you can do in this case is find the lowest Qts' driver available with the flattest measured mid-bass, lower mids BW and it is what it is since even at 50 Hz it's only a 0.2 Qts' and one reason why 80 Hz - up XOs are the norm for truly wide range systems.
[Qts']: [Qts] + any added series resistance [Rs]: http://www.mh-audio.nl/Calculators/newqts.html
I think much of the articulation in the bass response comes from good midrange response. I usually look for bass drivers that have a high Qms (low mechanical damping). I have found that light weight cones help also, look for a lower Mms (moving mass). A low Cms (mechanical compliance) makes the box size less critical.
I agree that a sealed box is a good way to go. I have had good luck with guitar drivers lately. The two woofers that you mentioned both look very nice, but you might look at something like an Eminence Double-T 15 for comparison. The low end response and shape is described as aggressive and tight/punchy.
I agree that a sealed box is a good way to go. I have had good luck with guitar drivers lately. The two woofers that you mentioned both look very nice, but you might look at something like an Eminence Double-T 15 for comparison. The low end response and shape is described as aggressive and tight/punchy.
Correct. Right, high Qms, low Rms, Mms.
Yeah, I've been 'biting my tongue' on some of the various 'best' threads as basic guitar and similar MI drivers are the pioneer's proven designs for the critical speech, instrumental BWs.
Yeah, I've been 'biting my tongue' on some of the various 'best' threads as basic guitar and similar MI drivers are the pioneer's proven designs for the critical speech, instrumental BWs.
The 15pr400 is a nice driver for what the OP is looking for ... too bad the prices have gone up so much recently. I've got a single in a sealed 190l box (175l net) and have an F10 of 35hz away from boundaries. I use a first order low shelf boost of about +6db. High pass @30Hz with a 0.8 Q. Nice smooth roll off in the low end, lower mid range is just great. Adds just the right amount of body to the sound. Run them up to 800hz 4th order.
Been tempted to try this vented in the same enclosure tuned to 30hz. Low end response looks the same except w/ported, a guy would be increasing the output by 4-5db ... if that's what is required. Xmax limit stays the same (around 20w vs 60-70w input taking in the sealed EQ used by me).
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