A few years ago, crackling and blowing out low-end was a common problem in earphones. Today, however, there's no shortage of budget and midrange pairs that can produce powerful bass response without distortion. A simple, inexpensive in-canal earphone like the $39.95 JBL Synchros E10 might have made waves in times past, but today it doesn't particularly impress. It offers deep bass response with zero distortion, but its sound signature lacks a crisp edge to keep the booming bass in check, and so can occasionally sound muted or muffled. It's hard to complain about its price, though, and the inline remote control adds value to this budget-friendly, bass-heavy option.

Design

The E10's ($39.99 at Amazon) simple design features a solid color design available in red, light blue, black, white, or purple and has few flourishes; the only real accent is the metallic panel on each earpiece that bears the JBL logo. The flat, linguini-style cable has an extremely narrow 3.5mm termination that should easily fit the bulkiest of phone and tablet cases.

An inline remote control with microphone sits along the left ear's cable at about chin level. It's a single button remote with no volume controls, but one tap will answer incoming calls or end those in progress, while multiple taps act as playback controls. The E10 ships with almost no accessories, just three pairs of silicon eartips in different sizes. It would've been nice to see a carrying pouch of some sort, even at this modest price.

Performance

On tracks with intense sub-bass content, like The Knife's "Silent Shout," the E10 delivers laudable thunder for its price range. The lows never distort, even at top (and unsafe) listening levels, nor do they ever sound restrained or thin. This is a beefy low frequency presence that fans of big bass will enjoy.

On tracks with more subdued bass response, like Bill Callahan's "Drover," we get a better overall sense of the E10's sound signature. Callahan's baritone vocals and the track's drums both get more bass boosting than they need, and the high-mids seem oddly sculpted. It sounds as if the mix is scooped out in crucial ranges, robbing the vocals of their treble edge and the overall mix of its high-mid crispness.

The E10's sound signature feels more at home on Jay-Z and Kanye West's "No Church in the Wild." It delivers the sub-bass synth hits with intensity, while the kick drum loop's attack gets just enough crunch to remain sharp and present in the mix. The vocals don't sound muffled, but they miss out on the same crisp boost that Callhan's voice could also have used. Not everyone will dislike this sound signature, but it's definitely a bass-forward, muted treble response.

Classical tracks, like the opening scene in John Adams' "The Gospel According to the Other Mary," are boosted in the low frequencies substantially, giving the lower register strings and percussion a stronger presence than they would normally have. The high-mids, meanwhile, don't suffer quite as much as they do on the pop mixes we tested, so the result is a crisp, bass-boosted presence that actually sounds quite favorable. It's not for purists with its pumped bass, but the E10 sculpts instrumental tracks in a pleasant manner.

It's hard to find much serious fault with a budget pair of earphones that deliver deep bass without any distortion. The E10's main issue is certainly its muted high-mid response, which throws off the balance of many tracks. If you're looking for a similar sound signature in this price range but with a more natural treble presence, consider the Urbanears Kransen ( at Amazon) or the NuForce NE-650M ($49.95 at Amazon) . If you like the big bass sound and have a bit more room in your budget, check out the Audio-Technica ATH-CKX7iS SonicFuel, and if you're looking to spend as little money as possible, the JLab Fit is a solid option in the extreme budget realm. For $40, the stylish, simple design of the JBL Synchros E10 will appeal to bass lovers, but anyone seeking crispness with their deep lows will want to look elsewhere.

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