The JBL ES30’s big draw is its .75-inch titanium laminate dome supertweeter that extends the speaker’s upper frequency limit to 40kHz! A second .75-inch tweeter covers the lower treble range, and a 6-inch cellulose-fiber woofer handles everything else. The dramatically tapered cabinet shape is kind of neat, but I found the wood-like and textured vinyl finishes less charming.
Tip: The ES30’s rear port may restrict near-wall placement options.
First things first: you might expect a speaker with two tweeters to sound “brighter” or more aggressively detailed than the competition, but that was not the case. The imaging had an unusually “open,” unboxy quality, and the midrange was pleasantly laid back. The stumble occurred in the bass; it didn’t fully match the purity of the mids and treble.
To fully evaluate the ES30’s super tweeter I listened to a bunch of Chesky and Telarc SACDs (these discs have more extended upper frequency response than CDs). On Sugar Hill: The Music of Duke Ellington and Billy Strayhorn [Chesky] the speakers’ resolution of detail, the shimmer of cymbals and overall clarity was breathtakingly good. Moving onto CD with Morphine’s The Night [Dreamworks], I was a little disappointed by the ES30’s grip on Mark Sandman’s two-string bass. Sandman’s low-down growl was missing in action, replaced with a thundering boom.