A bass lover’s ear bud, the FiiO F9

The FiiO F9 in-ear headphone's sound isn't by any stretch accurate or neutral, and it won't please persnickety audiophiles, but there's no denying the F9's sound is deliriously big and juicy. 

Bass is bold, highs are a little too sharp, but stereo imaging is wide open. The FiiO F9 sells for $99 and £109 on Amazon, and it's AU$139 in Australia.

Build quality and design really are first rate, frankly the best I've seen for the money. The F9 is a three-driver design with a single 9.2mm dynamic driver, plus two balanced armature drivers in each ear piece. Impedance is rated at 28 ohms. 

It also comes with two replaceable 1.2-meter cables, one fitted with a standard 3.5mm plug with an inline mic and controls, the other cable has a special 2.5mm "balanced" plug for use with some models of Astell & Kern portable music players. The F9 comes with a snazzy waterproof carry case.

I brought out a set of Final Audio Design E3000 in-ears for a round of comparisons, and frankly I much preferred the sound of the E3000. It's a more accurate, smoother-sounding headphone. And at $55, £49 or AU$99, it's a lot more affordable. True, the F9 feels more robust, and it's more comfortable, but the E3000 is a much, much clearer sounding device.

With music from "Live From The Artist's Den, Vol. 1" the F9's prominent bass and warm midrange took center stage with music from Ani DiFranco, Jakob Dylan, The Hold Steady, and so on. That made for a pleasant experience. But the next album, the Pixies' "Head Carrier," sounded bloated with fatiguing highs.

It's certainly not the sort of headphone that shines with all genres, the F9 wouldn't be my first choice for classical and acoustic jazz, or any recordings with pitched-up treble -- they sounded harsh with the F9, the E3000 is a smoother alternative. The F9 was a pleasure to listen to with well-recorded music, the sound was positively vivid, lively, and fun. The bass was terrific, and there was lots of it, but it was well-behaved and tuneful.

All of my listening tests up to this point were with my iPhone 6S, but I also tried the F9 with its balanced cable plugged into my Astell & Kern Kann portable music player. The F9's sound perked up a bit with the better player, but it's still too bright for my tastes.

All I'm saying here is if you don't like bright or overly bassy headphones the FiiO F9 won't be a ideal. That said, after I parked my audiophile sensibilities I mostly enjoyed the F9. As always sound quality is a matter of what you're looking for.

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