Ported or Sealed plus small sub with this woofer?

[Moondog55]

Many years ago when I first started playing around with speaker building the only drivers I could afford were the ones in the cheap bin at Tandy.
Some of these were surprisingly good tho until they were overdriven; which seemed to happen a lot.
Tandy/Radio Shack also sold the booklets and books by David Weems and GR Koonce which I bought. Always wanted to build the 3-Way using the Peerless plus Vifa set of drivers but by the time I had the money the Peerless 831709 subwoofer driver was Unobtanium.
A few years ago I bought a pair of Vifa M-22's from rabbitz and I think it's time I used the drivers to make that small 3-Way.
So the question is this; do I make an optimum ported box of about 40 litres tuned low or do I make them with a small sealed box and also make a small subwoofer to use with them
Mock-up of the combo on a slightly too small cardboard box baffle says sealed plus subwoofer might be the way to go but I would need to buy a driver as I don't think either of the cheap subwoofers I currently own could match the quality of the M-22
Second photo shows the current speakers using the same P-13 + D27 but using the bigger P-25WO-00-08 woofer in a large sealed box as per Sretens advice years ago, but those are a very very simple XO, only 3 elements in total and can't handle a lot of power for that reason, the P-13 is used wide open.
With the new speakers I'd like to be able to utilise a bit more power

 

[Moondog55]

Must be my search skills but I have not found a single documented build using this combination of drivers. Also the cost of passive components seems to have sky rocketed since I last bought anything. I can buy a Behringer CX unit plus a medium powered amplifier for much less than the cost of a low crossing passive XO and even a MiniDSP looks better value every time I shop around

 

[waxx]

It all depends on how much power you want to use. A ported 40L cabinet tuned to 35Hz will soon go in overexcursion, it is not stated how much the xmax is, but i guess somewhere between 4 and 8mm, and 8mm goes in overexcursion at 50w, 4mm at 25w. A sealed used with a sub crossovered at arround 100Hz can handle the full stated powerload without going in overexcursion, even with an xmax of only 4mm.

 

[waxx]

And take a look at the Scanspeak 26W-8534G00 subwoofer wich is relative cheap for 110€ down here. I used it in a sub and it's a pleasure to listen to (better than the B&W AWS610 i had before). You can make a big 150L ported box like i did with it and tune it to 25Hz if you want it that low. But smaller (and higher fs) is also possible. Even a 80L sealed sub with an F3 of 41Hz and (more important) an FS of 24Hz is possible with this 10" driver. Efficiency is in the same region as your M22 (89dB).

 

[Lojzek]

Definitely ported to optimally deploy the woofer

Your Vifa drivers are great. Think it would be a waste not to design an optimal filter (measurments), x/o points being 400Hz, 2500Hz. As a nice idea how to design a cabinet/stand combo might serve this compound 3. This is your build, so you are in charge.

 

[Moondog55]

I have a quad of them so I can experiment perhaps. What I don't have in the stash are a selection of subwoofer drivers. All I have is the pair of Cerwin Vegas, the Vega 124's.
Lojzek I was thinking 300 and 2700/3000 but only because I have those component values already here. So ported makes sense for a passive XO.
Listening to them sitting on the desk top with a cobbled XO and I think the baffle could be about 100mm wider, it is 330 at the moment, a common cardboard box width

 

[Moondog55]

Quick sim

 

[GM]

So the question is this; do I make an optimum ported box of about 40 litres tuned low or do I make them with a small sealed box and also make a small subwoofer to use with them

Second photo shows the current speakers using the same P-13 + D27 but using the bigger P-25WO-00-08 woofer in a large sealed box as per Sretens advice years ago

Hmm, the P-25WO-00-08 factory specs I have is 24 Hz Fs, 178 L Vas, 0.28 Qts, 4 mm Xmax, so no bass to speak of in a T/S max flat cab, though decent in a 'classic' ~Fs tuned 124 L MLTL.

GM

 

[Moondog55]

And yet the bass is better than the figures would lead you to believe; in the room it is being used in the bass is more than acceptable. And I still haven't made the subwoofers SWMBO has allowed me to fill the space under them [ still saving for the drivers] but I will eventually

 

[GM]

Yeah, for sure the room dominates, especially corners, but not knowing the particulars just simmed what I know normally works really good in a corner, simming >105 dB/m/20 Hz/4 mm/10 W. Not too shabby for a cheap 10".

GM

 

[midrange]

I have found that a commercial active sub gives a lot of flexibility for all my various projects. 2nd hand (REL, and MJ are good makes) wouldn't be much compared with drivers, crossovers etc.

 

[Moondog55]

One of the reasons I asked is that I have a couple of small [ 12"] active subs that are being replaced soon with bigger passives and outboard amplification. After listening to a few XO iterations yesterday I'm thinking of swapping the mid driver to a 4" and saving the P-13 to go with some bigger woofers

 

[GM]

Yeah didn't really answer your Q; a ~36 L [0.707 Qtc] sealed with an 80 Hz/4th order allows the P25 to handle its entire 120 Hz music power rating, so separate subs is the way to go.

GM

 

[Moondog55]

Then a 15 to 19 litre sealed box will do a nice small compact 3-Way using the M-22 and the Vifa M-11 as a midrange and I'll get one of the 12" woofers into a powered box to handle the bass duties
I may need some help thos as my Jeff Bagby program can't find the frds file I had for these drivers