Papa’s slot loaded open baffle version #2

[nicoch58]

Woofer EQ boost need only with low Qts like beta

 

[peppennino]

Not so sure... And 0,58 is not so low. Papa dislike hi QTS/small magnet woofer like Alpha

 

[Nelson Pass]

Me like big magnets.

 

[peppennino]

Voilà

 

[nautibuoy]

According to Blue Aran (speaker reseller website here in the UK) the Eminence Definimax 4015LF, Nelson's recommended bass unit, has been discontinued.

 

[nicoch58]

we know from 2009 that Pa like better beta BUT with +6db at 20 hz !
what you don't know is passive ob driver start at 0,7qts and alpha have is power problem too ,you must use two at last ,when move is qts sky rocket and sound bad....

 

[peppennino]

Nobody is using Alpha in this project and it is not intended for passive crossovers

 

[nautibuoy]

This unit looks as though it might be a viable alternative to the Definimax, TS parameters look to be reasonably close.

Faital Pro : Faital Pro 15HP1010 8 Ohm Push :: PS166.79 IN STOCK (23 Jun 2021)

Seems to 'come with a magnet' too.

Any thoughts?

 

[peppennino]

9mm xmax seems promising... QTS is lower than Beta

 

[Bigun]

I bought a bass driver to use with my Lowther but I suspect it’s not suited for the SLOB due to low Qts. It is a Precision Dynamics 153C001.
PD.153C001 | Precision Devices Loudspeakers

 

[Soundhappy]

Qts = 0.79
One unit (not pair) |15 Inch Woofer for Bass Compensation of Open Baffle or Cabinet | W-15 - Lii Audio, unique speaker, amplfier, quality and cost-saving parts for HiFi DIY

 

[nicoch58]

Nobody is using Alpha in this project and it is not intended for passive crossovers

All here know that

 

[Vix]

I had a Beta 15 in my OB. While not bad, next time I would choose a better woofer...
P. S. I heeard Alpha 15 as well. I was even less impressed...

 

[peppennino]

All here know that

And I obviously know the "0,7 rule" too. It's not me that insist with passive cross...

 

[peppennino]

I had a Beta 15 in my OB. While not bad, next time I would choose a better woofer...
P. S. I heeard Alpha 15 as well. I was even less impressed...

In what type of OB? In U-Frame my friend Mauro like very well his Goodwood 18 with B5, but here we have a "recipe" from Pa and we only need valid alternatives to Definimax

 

[Vix]

Plain simple OB...

 

[nautibuoy]

I had a Beta 15 in my OB. While not bad, next time I would choose a better woofer...
P. S. I heeard Alpha 15 as well. I was even less impressed...

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

 

[nautibuoy]

And I obviously know the "0,7 rule" too...

What is this rule (of thumb)?

The Definimax has a QTS of 0.5

 

[Soundhappy]

Interesting informations page I learn something more Understanding Loudspeaker Data | Eminence Speaker

 

[nautibuoy]

According to Blue Aran (speaker reseller website here in the UK) the Eminence Definimax 4015LF, Nelson's recommended bass unit, has been discontinued.

My bad!

The Definimax 4015ULF seems to still be available - that's the unit Papa used in his build.

Eminence : Eminence Definimax 4015ULF :: PS248.09