High Performance 3-way based on Bliesma M74A

Well that looks all nice! 🙂

T25A
M74A
26W/4867T
FA253

Should give pretty ultraclear SOTA System all components reasonable sized and budgeted. 👍
Honestly, I would take the RSS315HFA-8 for the woofer section. Somehow it fits the overall "alu cone/dome pistonic operation" style of the speaker better for convenience, and for pure subwoofer duty the Dayton can just stroke more air in the lows. You have to push it more, but as you have decided to go 4-way and give it a separate fat amp...

P.S.: Have you recognized that you probably build you endgame system there 😉
 
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Yes, a system befitting of Kendrick’s half time show

As for (sub)woofers, It’s different shades of grey.

As Jim said previously driver designer optimises for different things, depending on the intended market/application.

A THX/Atmos theatre “subwoofer@ does 32Hz to 120Hz for 115dB at the listening positions.

A stadium “subwoofer” does 40Hz to 200Hz with >140dB for listening at up to or beyond 100ft.

A home “subwoofer” aims for 20Hz to 80-160Hz i order around 105dB at the MLP.

The designer needs to pick his listening distance and SPL and decide on the cabinet size/weight before choosing the alignment Eg. Tapped horn/vented/sealed and then appropriate driver.

In re: XLS
When this was release around 1998-2000; to me it appeared that it was designed to be used with the matching passive radiator in a small 3/4 cu ft box.

in 2001; when with 25Hz and 105dB in 20L was considered very small (at the time)


Original Peerless (DK) XLS 12” 830500 specs and Application note:

Siegfried Linkwitz selected it as a the driver for a sealed box subwoofer ~2001
“Thor”

https://www.linkwitzlab.com/thor-design.htm

This inspired me to take a closer look at the original 10” XLS “830452”

https://techtalk.parts-express.com/...-new-again-peerless-xls-in-sealed-box-f3-23hz
 

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A good guide to find woofers suitable for HiFi is the ratio of the mechanical resistance to cone mass: Rms/Mms, or the Fs/Qms.
The lower, the better for Hifi, low Fs/Qms = detailed sound at low volume
If the woofer has a Fs/Qms of about 4 or less then it's a good candidate for HiFi
 
A good guide to find woofers suitable for HiFi is the ratio of the mechanical resistance to cone mass: Rms/Mms, or the Fs/Qms.
The lower, the better for Hifi, low Fs/Qms = detailed sound at low volume
If the woofer has a Fs/Qms of about 4 or less then it's a good candidate for HiFi
What is the "suitability for hifi", besides the often known thing that drivers with higher Qms have better bass response and are faster and more detailed?

And while that can be true for very low Qms drivers (Usher and Volt - which are always described as relaxed or even slow in case of Usher), but Wavecor and SB24 have similar or even higher qms than ScanSpeak, but everyone knows that SB and Wavecor is giving round and relaxed sound, while Scan Speak is very precise, fast driver with a lot of definition and slam, which is not the case with Wavecor and SB.

Usher 8948 has 1.98, Volt Radial 10 inch around 3, W, SB, SS 5-6

I am trying to say that W and S are worse/better than SS, just different, however, that one magic parameter is not telling the whole story.
 
And the easiest way to do it is to have x as close to 0 as possible. So that pretty much equals Sd as big as possible. But that way of thinking due to cone breakups is almost always getting us min 3 and most likely to 4 way speaker.

Still waiting for first person that will risk T34/M142 combination 🙂
 
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