We've grouped these six headphones together because they are all variations on the same drivers and thus sound very similar. But that's a good thing--you simply won't find better sound for for your money. All provide impressive bass for lightweight headphones, along with good midrange and detail. They differ mainly in their design:

KTX Pro 1 ($20): Your standard over-the-head portable 'phones, they also include an inline volume control.

KSC-35 ($30) and KSC-50 ($20): "Earclips"-- they hang over each ear with no headband to mess up your 'do. The KSC-35 are old-school favorites; despite their less than attractive design (think black plastic), these are among our favorite headphones of all time. The KSC-50 are their updated siblings, with a bulkier, rounder, silver look. We find that the KSC-35 fit a bit tighter, which in addition to making them better for exercising provides them with a bit more bass.

KSC-55 ($20): Koss' version of the behind-the-head "street-style" models. (If you have a large head, move along; the KSC-55 are clearly made for smaller noggins.)

SportaPro ($30): Hybrids--the headband can be used in an over-the-head or behind-the-head position.

PortaPro ($40): The upscale siblings of the other models here, the 70's-looking PortaPro offer better construction along with a fold-up headband and adjustable temple pressure settings.
--Dan Frakes

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