This current generation of the Reference series was released in 2014 and while it hasn't received the same marketing or sales presence as the long standing Primus line has. They have received some very positive reviews. Both Sound and Vision and Home Theater Review give the line solid praise. Infinity may have hit the nail on the head with this speaker and have a winner.
In addition to a general view and measurement showcase of the Reference r152's, I'll be comparing them with their cheaper but older brother and highly regarded budget speaker in its own right, the Primus p153. All while trying to get an idea of how much of a jump up in performance the r152 gets you.
Before we get into the technical details, let take a quick look at the physical and construction differences. Excuse the potato pictures.
Album of Infinity Reference r152 and Infinity Primus p153 product comparisons
Both speakers are currently only available in similar basic black wood grain vinyl. But even behind the grill, the r152 seems just a little nicer to look at. The lines on the r152 are a cleaner without the grill wrapping over the top of the cabinet, and the high gloss plastic where the logo is mounted is classy touch.
Taking the grills off changes things up a lot. The r152 have no exposed screws or mounting hardware, which also prohibited removal of the drivers. Aside from the color of the cones, the midranges look very similar. The tweeter sit's higher above the midrange driver but is contained within a large pretty shallow wave guide.
The r152's a pleasant to look at without the grills on, and don't share any of the p153's comparative toy like appearance.
Another big difference between the two speakers, is that the r152 actually has something the looks like a real port. The front port on the p152 doesn't amount to much more than a large hole drilled through the MFD speaker baffle. The rear port on the r152 is physically much larger and deeper and tuned deeper at about ~55hz, than the small front port on the p153 that is tuned to ~75hz. This high port tuning on the p153 is partly responsible for them not being bass monsters by any stretch and really needing a subwoofer to complement all the other things they do really well.
The Port is tuned to about 55hz and does a pretty good job in not creating excess noise. There is a bit of output centered around 900hz. though which appears to cause a minor wrinkle in the midrange.
The midrange and tweeter are crossed over at ~2.5khz. The midrange looks to have a touch of cone break up at 3khz, but again, it's at a pretty low output level and doesn't resolve into anything as the drivers integrate.
Overall the tweeter plays reasonably flat, with a low wide boost centered around 8.5khz; which I think is broad enough that it doesn't add any noticeable sibilance.
Grills are a bit of killer though and will be seen as such in the 1m measurements, so if possible I'd leave them off.