8″ Seas U22REX/P-SL with Swallow-BC

Seas U22REX/P-SL

Since I’m already setup to test 8″ woofers, I might as well throw in my Seas U22REX. Not that I want to build a speaker using this Seas U22REX with the Swallow-BC. It’s just that when doing AB testing, it’s important not to change anything. In this case, only the 8″ woofer is replaced with the Seas. The rest remains the same.

Manufacturer’s Thiele & Small Parameters

Seas U22REX Thiele & Small Parameters (DATS)

My DATS measurements of the U22REX are not the same as Seas. My Qts is 0.4 whereas Seas is at 0.29. This is a major departure. Faced with this set of differing figures, I modelled the box to see the difference.

Box Modelling with Seas T/S

With SEAS T/S, a 35 liters box optimal tuning is with a port of 3″ diameter having a length of 7.5″. System Q is at 0.58. That’s desirable. F3 is at 47Hz, low enough for my purpose.

Box Modelling with DATS

Using my DATS measurements with the same 35 liters box tuned to 41Hz, my System Q is at 0.703. That is perfectly fine. I do get a 1dB bump at the upper bass but I can accept that. It is with this box tuning that I will base my review on.

Sound of Seas U22REX/P-SL with the Swallow-BC

I played the same music as in the other reviews. Bela Fleck – UFO sounded incredible. The U22 control is extraordinary. All the bass nuances came out. There’s so much detail in the bass. Once you hear what is really in the recording, you wouldn’t want to listen with lesser woofers. It’s that much of a difference, like an epiphany.

The only woofers I have that are capable of this is the smaller 7″ Seas U18RNX/P and the 5-1/4″ Scanspeak 15WU/4741T00 Illuminator. These three woofers deserve 10/10. That is the standard all other woofers should strive for.

Now that I found a good 8″ woofer, my next project is to re-work the Blackbird-TA. I intend to replace the M8a with the U22. I believe that is the missing link that I’ve been searching for. Hopefully, the Blackbird will sound magical after that.