Volti v Charney v Rethm

You have picked three very good sounding speakers.  They are all lively sounding speakers.  The Rethm has, to me a little bit more of the horn and full range coloration, but, it is not that extreme.  The Rival can deliver deep bass and sounds good at high volume levels, but, I find the bass a touch disconnected from the mids and highs.  The Charneys, for my taste, are the best, but, to be clear, my priority is delivery of a lively sound at modest volume level—all three are very good in this respect but I like the Charney best.  I’ve heard them with Voxativ and AER drivers and like the AER more.

How big a room and how loud do you want your system to play and how important is really deep and powerful bass?  It is NOT the case that I found the Charney deficient in any aspect of performance, but, physics dictates that a single 8" driver cannot do all things as well as larger, multi-way drivers can do.  I would expect such limits would be more of a challenge for the Charneys than with the other speakers.  Still, I really love the sound of the Charney speakers and would recommend them for anyone not looking for head-banging volume in a large room.  

desltz,

Your large room and high ceiling might make bass reproduction difficult for some speakers.  My bet would be on the Rivals, among the three choices, working the best in that situation.  But, these days, many single driver or small driver two-way systems are quite capable to performing well in large spaces.

I heard a system that employed a single 8" fullrange driver, but, it was supplemented with active woofers coming in to handle deep bass.  It was shown at an audio show in a fairly large ballroom.  I was surprised at how good it sounded and how well it filled the space and played at very high volume level.  The speaker was the Cube Audio Nenuphar Basis speaker.  

I also heard two-way Acora speakers demonstrated in a large ballroom also do a good job filling the space and providing adequate bass.  

If one can place the speaker near a corner, Audio Note AN-E speakers, which utilize an 8" woofer and a dome tweeter sound terrific and can fill large spaces and deliver fairly high volume.  

I too love the Pure Audio Project Quintet 15 speakers.  I heard them with the center horn driver too, but, I would really love to hear them with the Voxativ fieldcoil driver-I have heard that driver in another system and it delivers a very vivid and lively sound.  Even with four 15" drivers, my concern would be bass energy in a large room because of cancellation of the front and back output which are out of phase (this reduces bass by 6 db/octave).

This is still an excellent recommendation that is consistent with the kind of sound that would be delivered by the likes of Charney, Rethm and Volti speakers.  An important reason for picking these kinds of speakers, to me, is that they can be driven by lower-powered tube amps which are my favorite kind of amp.  While a SET amp might not not be ideal, given the size of the room (the Charney might be efficient enough), there are many good lower-powered pushpull amps and a few OTL amps that would work well.  

I was impressed with the bass of both the Quintet and Trio speakers I heard because I like fast and nimble woofers that can keep up with the kinds of midrange/treble drivers they use which are also very fast and dynamic sounding.  I also saw that PAP employs the kind of woofers I like which use pleated paper surrounds—those tend to deliver very clean and articulate bass—but because they also limit excursion, they don’t deliver deep bass at high volume levels.  I admit that I don’t prioritize extremely deep bass, so I did not evaluate the PAP speakers I heard for that aspect of performance.  My “concern” was hypothetical and raised as something to look into rather than something I actually heard.

I did see that PAP did employ one approach to reducing back wave cancellation—they effectively widened the baffle with small side supports that extend backwards like the side of a conventional speaker with no back.  This is commonly done with open baffle designs.  It is generally considered better to “widen” the baffle with such wings than to use a wide front panel because of problems with reflections off a wide baffle and diffraction issues.

Aside from the particular demands here--large room and high ceilings—my favorite speakers mentioned here are the Charney Companions with AER drivers and the Quintets.  If corner placement works, I would add the fieldcoil version of the Audio Note AN-E to my personal favorite list.