Why do music lovers put up with cheap stock earbuds? You've spent hundreds of dollars on an MP3 player then effectively nullify your investment with headphones that suck the soul out of the music that you love. Choosing a higher-end set of earphones is almost impossible, since there are way too many, and they are deliberately marketed to blur the distinctions from best to worst. I tried out $2,000 worth of in-ear earphones—16 pairs made it to my final evaluation—and since I like you, I will share the results of my hours of ear penetration.

First, some ground rules on the scope and purpose of my testing:

The headphones tested are all what you'd consider "upgrades" rather than "replacements" for the crap headphones that came with your MP3 player. While I capped pricing at $200, my "cheapest" pair started at around $40. The three tiers are under $100, $100-$150, and $150-$200.

The most practical measure of sound quality is to just sit and listen. I focused on in-ear headphones because they are built not just to jam a driver right next to your ear, but to block outside noise. It's simple: less ambient noise = better experience.

In the spirit of cutting aside the science-based marketing jargon, my tests were unscientific, but consistent across the board and based on real-world situations. The methodology was simple: a current-gen iPod, a sonically diverse playlist of music and, for isolation testing, a seat on the 14 bus in San Francisco, then some time next to a white noise machine.

With so much of the earphone inside of your ear, rustling of the cable can cause some serious noise. If the cable isn't properly buffered from the earphone, the deep, annoying shuffling can interfere your music when you try to walk or turn your head. That's why I made note of "cable noise"—this isn't to suggest there was some kind of buzz or white noise from the cable itself.

Here are the results of my testing:

Under $100
The Winner: Ultimate Ears metro.fi 2 Along with providing great sound and a decent fit, this set appeals to your normal side. The earbuds are as pleasing to the eye as they are to the ear, with a tasteful matte finish and an almost flush fit. In other words, you don't feel as ridiculous as you might with the Shure ear-garrotes or some of the other Ultimate Ears' protruding Frankenstein monster plugs. They don't sit too deep, so if you're apprehensive about the ear-rapey aspect of other offerings, you'll be comfortable with these. The sound, though emphasizing the low end, is clear and competitive with much more expensive units.

The Losers: This is a tricky price point, as some stock earbuds (Apple, Sony) are actually pretty good. Slapping a rubber cuff on a half-baked product doesn't justify a price of $50+. In the case of Apple's in-ears and the CX300, you aren't really experiencing a different class of audio than with stock buds, though there is a marked improvement. The CX500s put on a good show for bass junkies, but that's about it. Creative has a nice product with a great price, but it just can't measure up to the metro.fi on the performance front.

$100-$150
The Winner: Shure SE110 This price point offers the highest price to performance ratio, and the SE110 is the best of the lot. If you can get over the deep penetration and the over-ear looping, you'll find that the SE110s are comfortable, block out plenty of ambient noise and most importantly produce stunning, immersive sound. The tones are wisely balanced, and quality is at the level that you'll be noticing new things about songs that you've heard dozens of times. Decent discounts are available at various online retailers, as is the case with most of this category.

The Losers: Manufacturers know that this is a sweet spot for consumers, so the market is crowded with good options. The hardware starts to look a little more "professional," or more accurately, "weird." Etymotics, always fans of producing earphones that are really good on paper, fails with the ER6 not because of quality issues, but because the buds are awkward and overwhelm with the high and middle tones. The company's new earphone tips, however, are amazing (more on this below, in the more expensive category). Ultimate Ears loses their luster at this level. Creative is yet again a nice runner-up; the Zen Aurvanas are very capable, but couldn't supplant the crystal-clear SE110s.

$150-$200
The Winner: Etymotics hf5 Ostensibly designed with portable music players in mind, the hf5s solve the balance problems of the er6 models and much, much more. They're cool looking (with the right tips, they look like sci-fi laser pistols), have little to no cable movement noise and reproduce sound in a way that is both perfectly clear and highly enjoyable. Everything about these gives the impression of quality, from the brushed aluminum finish to the way that music suddenly sounds distinctly layered in a way that it didn't before, and that it doesn't on many similarly priced units. One caveat, though: the hf5s (and the er6s, for that matter) must be used with the new foam rubber tips, called "Mushrooms." They're a little phallic and sort of a sickly gray, but they are leaps and bounds better than Etymotics' trademark flanged tips. The tighter seal that these offer to most people is conducive to better listening, and the isolation properties are superb. You can't hear anything else with these guys in. Every manufacturer should have something like this. According to the Etymotics people, by the time the hf5s ship these will be standard issue. Good.

The Losers: To sum up the category: Expensive without enough added benefit. Spending $100 will get you a phenomenal listening experience, so it's hard to justify spending more. The $200 cap was intended to filter out the luxury market/audiophile products that tend to show up at about that price, but hints of both are apparent here. The Shure SE210s are a wonderful pair of earphones, but the large premium over the SE110s is a dealbreaker, as side-by-side comparisons expose only the slightest variation in sound quality. The Klipsch Custom-2s are more of a luxury item than the others, with woven cable housing and a case that is ready for you iPod as well. Harman Kardon is just batting out of their league here, and Ultimate Ears doesn't improve on their cheaper models, even introducing some pretty terrible cable noise.

If you're looking to get the most out of your MP3 player, you'll have to spend some money. But as it turns out, the general rule is that once you pass about $100, your audio improvements will become smaller and more expensive. After reviewing all of these earphones, one simple fact is very clear: If I were in the market for a new set of earphones, I would buy the SE110s.