Pure Audio Project open baffle speakers

I agree with Ozzy regarding the quality of bass from the Spatial X series.  I have the X5 which has the powered 12 inch woofer rather than the 15 inch powered woofer of the X3.  My room is a difficult room for bass as it is only 11 feet wide by 24 feet long and has 7 foot ceilings.  I have several bass traps which helped my previous two rel subs but still the bass was never as tight as I would have liked.
The bass quality is much much better with the Spatial X5s and my intention prior to purchasing the X5s was to still use the two rel subs but just cross them lower.

I have mine 50 inches from the front wall and almost 8 feet apart and toed in to almost point at my ears and I sit about 10 feet apart.  I prefer 10 feet away than 8 feet away, the drivers seem to integrate better but I only have about 40 hours on them so I know they will improve with break in.

However I was shocked at the bass quantity and quality and have removed the rels as they do not benefit the bass and actually subtract from the bass quality compared to the X5s alone.

If I had a larger room I would have gone with the X3 but Clayton recommended the X5 for my room and I also thought I would still use the subs but they are now in storage.  
The reproduction of the bass guitar on these speakers is outstanding with very good pitch definition and the speakers go down into the upper 20s according to my test cd.

mrotino,

You have only scratched the surface with 40 hours on the speakers. Mine improved up to and beyond 300 hours. The bass will benefit the most, becoming more prodigious with better presence and slam with kick drum and electric bass guitar. It does get much better than what you hear now.

Oz

Yes Ozzy that's what I've heard from many owners which is hard to believe as the bass is already quite good and much better than what I had previously.  It's difficult for me to play them continuously since my family doesn't like it unfortunately.  Anyway I'll try to get more hours on them and look forward to the improvements as well.
I've heard the 100 hour point is significant and that they continually improve as you've mentioned beyond that as well.

To the OP, I reviewed both the PAP Trio15 line (Tang Band, Voxativ, and Horn1), as well as the Tri-Art Audio Series B 5 Open for Dagogo.com 

Every OB speaker has its own design and build characteristics. "Better" is quite subjective. I can set up either of these quite different designs in systems that are captivating. You should familiarize yourself with the primary drivers available and try to gain understanding about how they would sound generally, apart from particular brand, i.e. horn, full range, concentric, etc. 

For your more sizable space I would look at the Quintet rather than the Trio. Due to the arc of the front baffle I wouldn't be concerned about the speaker's top being 1' from ceiling. The horn is exquisitely refined and when set up optimally is stunning in resolution and center image focus. My understanding is that the field coil driver is much better, but I haven't laid hands on it. 

I have a set of PAP Trio with Horn 1 midrange. They replaced a set of B&W 803Ds. Here are my impressions:

I am using the Leonides XO. Have very mixed feelings about this XO. It is a first order XO and does little to roll off either the bass drivers or the Horn 1 midrange. The Horn 1 is good down to 300 Hz or so, and the bass drivers go all the way up to 1500 to 2K Hz (where they have a nasty peak). So there is a large area in the lower midrange where both the Horn 1 and the bass drivers are active. I added an RC network to the bass drivers to try to attenuate the upper midrange somewhat, and it works after a fashion but is not perfect. The speaker sounds great on Jazz but is trying for compressed rock. Am in the process of looking at an active XO system so I can better roll off the horn and the bass drivers at about 800 Hz.

Compared to the B&Ws, the imaging and sound stage depth is vastly better. Even with the frequency response issues, these have much better upper midrange (not as harsh and they don't "beam" like the 803s did). Bass is quite good compared to the B&Ws, which surprised me.

I also have the Voxative drivers which I have yet to try, and may swap these for the horn. The horns use Beyma Spanish made drivers and are incredibly efficient, at 108 dB/Watt. May also take a look at the ESS drivers as these are quite inexpensive at the moment.

I do have to comment on the CS from this company. Ze'ev is quite responsive until he has your money, thereafter not so much. His business model is to drop ship the components from all over the world, so the user has to assemble and test the speaker. We had a number of QC problems (the initial shipment of woofers were damaged by the manufacturer in packaging) and many of the parts were quite late in delivery.

So for me these are a work in progress, which I don't mind so much as I am a tweaker. I think they have real potential if the frequency response aberrations can be brought under control.