Aperion Audio has spent years refining how speakers handle the highest frequencies. The PST MKII Planar-Ribbon Super Tweeter pair is designed to sit on top of your existing speakers, extending the treble range from 8,000 Hz all the way up to 40,000 Hz. This isn’t about adding harshness or sibilance. The planar-ribbon driver handles those frequencies with a delicacy that horn tweeters often miss, adding air and space to cymbals, string harmonics, and vocal sibilants without sounding aggressive.

The pair comes with five preset crossover points, letting you dial in exactly how much high-frequency extension you want. You can match them to bookshelf or floorstanding speakers from most brands without issue. The wood enclosures are finished in gloss cherry, which looks natural sitting on top of black or wood-grained cabinets. The tabletop mount design means placement is simple, though you’ll want to make sure your speaker tops are flat and stable.

At around $500 for the pair, these are an upgrade for listeners who feel their current system is slightly rolled off on top. They won’t fix a poorly positioned room or muddy midrange. But if your speakers already sound good and you just want more sparkle and decay in the treble, this is a clean, effective solution. The difference is subtle until you take them out of the system, then you’ll notice the air disappear.