Audio-Technica makes a lot of headphones and several of them, including the ATH-M50 ($160) and ATH-M30 ($60), offer excellent sound for the money. The company's ATH-WS55 Solid Bass, a smaller over-the-ear headphone, isn't as well known as those models, but it, too, delivers solid bang for the buck for a bit less than $100. While it may not be the most comfortable headphone for long listening sessions, it does indeed deliver very "solid" bass without sacrificing the performance of the midrange and treble. If there's such a thing as an affordable audiophile headphone, the ATH-WS55 fits that description.
The headphones appear to be well constructed with earcups that have aluminum backs (the headphones are available in a few different colors); they also fold flat but do not fold up for more compact storage.
The headband and earcups are pretty nicely padded, though I can't say this model is incredibly comfortable. Part of the reason for that is that the earcup is a little smaller than your typical over-the-ear model. I liked that they're more compact and well suited for mobile use, but they felt a little tight on my ears, so I ended up having to adjust them every 5 to 10 minutes. I found that they fit best if I placed the headband slightly back on my head rather than straight over the top of it (in the middle). The angle takes a little pressure off.
Unlike the ATH-M50 and ATH-M30, these guys have a dual-cord rather than single-cord design (each earcup has a cord coming out of it). While those cords aren't as thick as the single cord on the aforementioned models, which are ostensibly "studio monitor" headphones, the WS55's cords are still comparatively beefy and seem durable. You also get an L-shaped plug, which most people consider more durable than straight plugs. However, if you have a smartphone with a thicker, tough case on it, you may not be able to get the plug into your phone's headphone jack.
You don't really get anything as far as extra features go. There's a step-up model, the ATH-WS55i, which includes an inline remote and microphone, but it appears to be a "Japan Import" and is a bit difficult to find here in the U.S. That's a shame. There's also the AT-WS70, which you can pick up for around $120 ($150 list) and has a bit swankier design with a similar fit.
As I said, the bass is really punchy without being overbearing or causing the headphones to vibrate at higher volumes. And while this is labeled as a "bass" headphone -- it has 40mm drivers -- it's well-balanced with impressive detail and a sound profile that leans toward a warmer, more natural vibe. You'll get more detail and bass out of the ATH-50, which has more-refined sound, but you could say this is a good compromise between the M50 and M30, particularly for mobile users.