JA - I can share what little I know, and perhaps others can fill in some blanks. I’ve not seen a ViewPoint system except in reviews and photos.
There is one PowerDriver, Thiel’s 6.5" x 1" concentric/coincident driver. The woofer and tweeter systems are both shared by the CS7.2. This woofer has different motor parameters than the SCS, CS1.5, etc which are optimized for reflex bass. This PowerWoofer is optimized for sealed bass. It uses neodymimum magnets and the shallow, exponentially curved front cone optimized for its wave-guide functions for the coaxial tweeter. The backing brace is a straight-sided, deep cone of cast styrofoam without the back skin of the 7.2 upper woofer. Early versions of these drivers were made in the Lexington factory and featured a removable tweeter module to facilitate repair.
The tweeter is shared by the 7.2, and (I think) has the silk surround and catenary dome geometry. That opinion is part speculation and part observation. My (scores of) swept measurements show the oil-can breakup to be very controlled and above 30kHz. I’ve never seen that (great) behavior from a spherical dome or rubber surround.
Before the SCS4s, my experience with this PowerDriver was in the PowerPoints. I have 4 pair at various levels of upgrade, plus two pairs of SCS4s presently in the lab. Every individual driver measures like the same driver. Clones.
Both the PowerPoint and the ViewPoint share the 45° launch geometry where one plane of the driver’s wavelaunch is supported by a 45° wall plane at the driver rim to eliminate wall-bounce as an installation problem. The propagation into the room is orderly and organized and the bass is supported without a suck-out / bounce (which must always be managed in a floor-standing or stand-mount speaker).
The PP is flat to 80Hz with a sealed box 12dB / octave roll-off below that. The viewpoint (which I have never seen or heard) claims -3dB bass to 60Hz. That extra bass probably comes from tangential 45° mounting to both the wall and the monitor screen itself for a larger (quasi infinite) baffle. The in-ceiling (HigherPlane & PowerPlane) have differing tunings, but all use the same PowerDriver and all are sealed, so all mate very well with subwoofers. Thiel supplied either an external crossover tuned to each model or the Integrator which could control multiple model mixes. That low bandpass crossover introduced two more poles (12dB/octave) to create a now-conventional 4th order in-polarity low crossover. (Some of you know that I take issue with 4th order slopes, but it does create a powerfully practical solution.) All the enclosures are aluminum and all the crossovers use Thiel’s styrene/tin film & foil ’yellow’ 1uF bypass cap.
I have seen several pairs of SCS4 and PowerPoint speakers which all exhibit the pains of transferring manufacture from Lexington with long-established Western components and point-to-point in-house construction - to later FST / Chinese executions with diminished x progressively improving components and execution (beginning with fairly shoddy and progressing to fairly fine.)
This migration to China was done to down-size the Lexington plant as Jim’s attempt for a simplified down-sized manufacturing operation to have a chance of survival after he was gone.
I am presently researching how the FST non-removable tweeter might (or might not) be adjustable in launch-plane. Its transient arrival is a few micro-seconds too soon and I hope to ’fix’ that as a point of honor to Thiel’s goal of best-of-form phase/time wavefront integrity. I know the problem's magnitude is in the dust, but still hope to clean it up if I can.
Back to the ViewPoint. All units were custom made by trimming the extrusion to match the height of the mating monitor. I suspect (but haven’t confirmed) that the actual driver enclosure volume is fixed and the extrusion length merely acts as baffle extensions. The written and verbal reviews have been consistently stellar. I look forward to learning the particulars of crossover position and feed-wire routing. I do know that the PowerPoint XO is positioned tangent to the driver magnet(s), which is the least harmful place - whereas the SCS4 XO is positioned directly behind the magnet(s), which has the highest level EMF radiation / interaction. I am once-again surprised and pleased in my SCS4 project by the improvement gained by better physical implementation of those physical aspects. (which of course are always more cumbersome and expensive to implement.)
I welcome and encourage any of you with experience of the PowerDriver, especially the ViewPoint, to chime in with your experience, further thoughts and corrections of any of my conjectures.
Cheers, Tom
