If you happen to bump into us on the street in the next few days and we can't make out a word you're saying, well, here's why -- we recently had the opportunity to spend plenty of quality time with Shure's latest pride and joy, their flagship E500PTH earphones. Shure's been talking up the E500 for the better part of this year as a "new paradigm" in personal sound, but audioheads (with the prerequisite $500 to burn, that is) have only been able to find 'em in the retail channel for a few weeks now. Much like the E5c before it, Shure bills the E500 as the be-all, end-all solution to portable reference-quality sound reproduction, thanks in no small part to the three -- count 'em, three drivers in each bud. But unlike the E5c, the E500 has an arguably more compelling trick up its sleeve: its unique push-to-hear (PTH) module, which allows the wearer to switch between audio input and ambient sound at the flick of a switch. While our poor, buzzing ears are recovering from the constant barrage of sweet sounds they received in the name of conducting a proper writeup, we figure we'd hunker down and actually get this thing written, so read on for our full pictorial review.

First off, we'd like to give Shure props for presenting the E500s in packaging materials worthy of their lofty sticker price; you'll find none of that ridiculous, seemingly bullet-proof plastic here. Open the outer cardboard shell and you're greeted by an attractive brushed natural metal box sporting a black metal lid. Of course, this box is not your carrying case, and after you open the packaging for the first time you may never see it again, but it's always nice to get immediate positive reinforcement of your pricey investment.

Before we go into the finer details of the E500's sound reproduction, let's get the push-to-hear module out of the way. The bottom line: it works as advertised. The module, which Shure sells independently of the buds for $60, consists of a Swiss Army Knife-sized pod with a switch, a green LED to indicate PTH is active, and accepts a single AAA battery (included) for operation. PTH volume is controlled via a wheel on the module's side, inset sufficiently to prevent accidental changes.

When enabled, audio input (your music, that is) remains barely audible in the background, but the mic input takes over the lion's share of what you hear. The effect is a bit weird and requires some getting used to, because it seems as though you're listening to a low-fidelity recording of everything around you -- but hearing what folks nearby are saying is easy enough. The mic itself is located in the female jack, the end you'll plug your earphones into; the location's good because it's positioned far enough away from your mouth to reproduce your own voice at an excessive volume, though we found it had a tendency to flop around a bit against our clothing, leading to some static sounds.

We've got four niggles with the PTH unit, none of which are sufficient to deny it our undying affection. First, the switch is a bit difficult to operate, and feels like it could realistically wear out before terribly long with heavy use. We would've much preferred a toggle button with PTH on when pressed in, off when out; something to that effect. Second, we thought the unit felt just a little cheap. The wiring is definitely of sufficient gauge for a product of this caliber, but the switch module itself feels like lightweight, flimsy plastic, and the battery door popped open of its own accord on a couple occasions. Third, all told, it's pretty flippin' big. It more than doubles the traveling size of your earphones and is somewhat inconvenient to wear on your clothing, meaning it's best left behind unless you know you'll be in a situation where it's helpful. Fourth, having PTH gave us a problem we'd never had with in-ear buds before; interruptions don't mean removing the buds. You have the luxury of leaving them in for many hours at a time if you so choose, and in the process, they can become extremely uncomfortable. Also, did we mention people seem to think you're kind of a jerk when you don't take out your earphones when talking to them?

Now on to the buds themselves. They're attractive, feel exceptionally well built, and for their bulk they're surprisingly comfortable in the ear. The quality and depth of sound reproduction is frankly mind-blowing, and seems to almost taunt the user to kick the volume up a few notches. For comparison, we pitted the E500 against Sony's venerable $50 MDR-EX71SL and to Shure's own $200 E3c.

The Sony EX17SL is a popular, serviceable headset that we use ourselves for regular duty in situations where neither sound isolation nor reproduction are of the utmost importance (say, jogging). When put up against the E500 there's simply no contest, but this is a situation where "ignorance is bliss" definitely applies. We had no idea just how bad the Sonys were until we plugged in the E500s, and since, using the Sonys has actually become an unpleasant experience. In other words, if you own EX71SLs, don't try the E500 unless you plan on buying it.

The distinction between the E3c and the E500 is much finer, and definitely open to some amount of argument and interpretation. The E3c is an excellent headset by all standards, but it has been occasionally faulted for lacking low-end punch -- this has lead some to bill it as being well suited primarily for classical music. That being said, it's still a far better set of phones than the average iPod user will experience (for any kind of music) and features superb sound isolation, particularly when paired with the optional triple-flange buds. Needless to say, with three individual drivers, the E500 delivers all the low (and medium and high) end you could possibly want. We also perceived sound isolation to be slightly better, though we didn't conduct a blind test and it could've just been the price difference talking to us. So do the E500s sound better? Yes, absolutely. We even found them to fit our ears better. But are they worth the extra $300 over the also very good E3cs? That's very hard to say, and depends on the listener's ears, intended use, and budget. We strongly recommend you track down a brick-and-mortar retailer and try them all for yourself before committing the cash.

The E500 comes with an strong bundle of accessories, including an inline volume limiter, an extension cable (great for use when you're not toting the PTH module), a variety of foam, triple-flange, soft and hard buds, a 3.5mm to 1/4-inch adapter, and a hard carrying case. The case is oblong and lacks Shure's typical center spool in order to accommodate the PTH module, which is a shame -- the spool is the best feature of the cases included with their lesser models. Without it, expect the occasional tangle. For $500, we'd have liked Shure to include both case types for the times the PTH stays at home.

In the end, yes: the E500s are simply the best earphones we've ever tried, and one of the best experiences we've had listening to music, period. Alas, the price tag will keep 'em firmly planted in the niche market. At the PTH module's more palatable $60 cost of entry, though, it's a worthy upgrade for owners of any buds tired of undoing their setup every time they get a tap on the shoulder. Just be warned, if it's a good friend or your significant other, do yourself a favor and pull out those buds anyway.