Papa’s slot loaded open baffle version #2

Looking at your pictures, it might be worth experimenting some side 'wings' before concluding that the bass driver is the problem?

Don't want to get off topic, but initially there were side wings, which I later removed. It became uglier, but the sound improved. There was less quantity of bass, but it's quality improved. There was less resonance and...maybe I understand why some folks are baffled by the lack of baffles :D

But, all I want to say here is: If you can afford more expensive bass speaker (than Beta 15) go for it...
 
What is this rule (of thumb)?

The Definimax has a QTS of 0.5

From Soundhappy's link @Eminence website:

"As a general guideline, Qts of 0.4 or below indicates a transducer well suited to a vented enclosure. Qts between 0.4 and 0.7 indicates suitability for a sealed enclosure. Qts of 0.7 or above indicates suitability for free-air or infinite baffle applications."

Slotted OB are quite different and SLOB are normally used with B5, ACN or MiniDSP.
From original Papa's SLOB article with multiple woofers:

"It's easier to use an active crossover when you want quick results. You just adjust the crossover filters, measure, listen, and then repeat the process until you're happy. It did not take me long to get good results because the mating of the woofer and tweeter were well behaved. I used a 2 pole low pass filter for the bottom at 80 Hz and a 2 pole high pass filter at 160 Hz, and because I am lucky the proper response was with both drivers in phase.
Some equalization was called for on both drivers. The woofer received a high Q high pass filter at 20 Hz which removed subsonics and gave the response a 6 dB bump up at 20 Hz. The Lowther enjoys 4 dB of step correction above 2 Khz or so to take down the overall top end. If you are a little off-axis, you might decide that 2 dB is better"
:cheers:
 
Cheers peppinnino, I was just catching up on Soundhappy's link when your post arrived.

I get the general rules of thumb you mention, however, and in retrospect I didn't put this very well, I was questioning if the SLOB is a different use case where those rules of thumb don't work as well - when looking for alternative bass drivers to the Definimax, do we know what the important parameters are in the the SLOB context?
 
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Also Troels Gravesen (that has a completely different audio philosophy) abandoned hi Qts driver for low with powerful magnets in OB. Here Faital 15PR400 with a Qts of 0.33 in OB with passive eq:

red-600-faital-fromxo-vs-no-xover.gif

OBL-15
 
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I’m just about done reworking some baffles I made a while ago to fit a pair of the Lii Crystal 10 drivers in.

The woofers will be AE Dipole 15 driven by Hypex amps.

I am think the one AE 15 will do the job, if not, I will add a slot chamber below with an AE Dipole 18.

I found all my sets of drivers used at a huge discount. You just have to be patient and keep checking various online classifieds.

I’ll run these active with a B5 I also got used.

I want to do a “showdown” between my ACA and F2J monoblocks and my new VFET amp on the top end.
 

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