2 x SB20PFCR30-8 vs 1 x 10-12" as woofer in a 3-way

[Mircenzo]

Hi,

I'm about to build a 3-way with a 6,5" Midrange(Sensitivity 94db), crossing to woofer at 350-400Hz.
Box volume flexible but preferably max 70L. Listening level around 90-95db at 2.5m. Target: f6 around 50Hz but the lower the better.
Everything is to be powered by a Hypex FA123(75W per channel) therefore higher sensitivity is key.

I have from a previous project 4x SB20PFCR30-8 which could be used 2 per side and model well in a closed box(see attachment). Total Sensitivity for both in parallel 96,5 dB and need only 34L.
I have never played with a more expensive woofer and therefore am afraid of missing on something.

Are there advantages having 1x 10-12" woofer vs 2xSB20PFCR30-8 ?

Which 10-12" would you recommend for a closed box and higher sensitivity ?
I am looking at PHL3411 and PHL4021 but I am not sure how they test in a closed box. Modeling does not seem much better than my 2x8".

Provided the 2xSB20PFCR30-8 will not be pushed hard, will I be losing on dynamics and "tightness" in the bass region ?

Would appreciate any advice.

 

[planet10]

With 2 woofers you can mount them push-push which would a big consideration for me.

The actual XO should take the bafflestep diffraction roll-off point. And a 6.5” above should be ableto golower.

dave

 

[Rokytheman]

Several years ago I for fun tested two of those drivers in similar cabinet size - to be more exaxt i think it was around 45-60 liters. I was green in crossover and maybe pure luck. But I liked the sound and actually one of those memories that Will forever stick. So much Im returning to similar Concept, but with Dayton RS225 alu.

Dont expect miracles with the drivers. I would start with those you have and give Them a try. Build baffle so you could change later when you get the itch.

Dont be afraid to EQ with Linkwitz Transform.

 

[Mircenzo]

With 2 woofers you can mount them push-push which would a big consideration for me.

The actual XO should take the bafflestep diffraction roll-off point. And a 6.5” above should be ableto golower.

dave

I believe the push-push is more for subs than woofers at 400Hz ?
The 6,5" is a PHL1130 which cannot go lower than 300-400Hz. XO point will be defined after the woofer section of the box is clear.

 

[planet10]

The push-push woofers in Tysen V2 cross at 450 Hz. I was surprised when Aaron presented his results.

Bass is essentailly omnidirectional.

I also would not puh the woofers that high. Especially a 12”.

dave