Pros - Lightweight, great sound, low price, easy to power, comes in nice packaging, looks clean, compact, fairly comfortable.
Cons - mostly plastic build but its perfectly fine. The sound is quite astonishing for the $55 paid.
These headphones are a steal at the price I got them at. Sennheiser has a standard 2 year warranty on them when registered. There's nothing bad to say. Honestly, if you want a pair of travel headphones that sound great without breaking the bank, these are the way to go. I was a little opposed to the idea of on-ear headphones but these are pretty comfortable. I'm no sound expert but these easily score a 4.5/5 in my standards.
I recently discovered that these headphones are discontinued from Sennheiser's website, now replaced with the slightly tweaked HD239 model (MSRP $120 USD).
I actually won these headphones through the weekly giveaway sweepstakes from Headphones.com. If I recall correctly, the HD238 was sold there for around $100 USD. I have to personally thank fellow Head-Fier and employee of Headphones.com, David Mahler, once more for making the transaction smooth.
I did a silent unboxing/written review of these on YouTube if you are interested (the review is different from the one given here, it is more condensed).
What's in the box? Sennheiser HD238 headphone 1 black fabric carrying pouch with drawstring-secured opening
2 year limited warranty
Comfort For the most part, the HD238 is fairly comfortable. The earpads have fabric (felt? velour?) on the outside, foam on the inside, with a pleather section that touches your ears (with the exception of a more porous fabric for the ear hole). Keep in mind that it is a supra-aural headphone however. Because of this, I find that the earpads warm up pretty quickly. Also, when worn for more than an hour at a time, for me at least (during a 2-hour Skype chat), the earpads start to hurt my ear. With glasses on, this problem occurs more often. This happens to me with all supra-aural headphones though, so your mileage may vary.
In terms of size, the HD238 has a very small headband. I would not recommend it for people with larger heads (see the "Durability" section below). However, the lightweight design and padding at the top of the headband make it a comfortable headphone to wear. Sometimes I find it a relief when the HD238 is on my head instead of my heavier Shure SRH940. Its low profile and light weight on the head makes it a good headphone for moving around with. I would call it a "sports friendly" headphone.
The earcups of the HD238 both swivel 180˚ and pivot vertically, making it fairly easy for the earpads to reach one's ears at the right angle.
^My awesome photo-editing skills
Noise Isolation and Leakage Being an open-back headphone, the HD238 provides very little noise isolation and does leak a little. While listening to music at reasonable volume levels in a quiet room (such as the library), the leakage is minimal. The lack of noise isolation might be good for some (such as myself while at home) who want to hear someone talking while still listening to your music.
Durability Though top the headband of the HD238 is flexible in the sense that it might be able to accommodate wide heads, the sides of the headband, including the adjustable parts, are made of a very lightweight and stiff plastic. It seems durable, but I would be cautious when flexing the HD238 for larger heads.
Now for the cable...as many have already said, the cable on the HD238 is extremely thin and flimsy. I would be worried if the cable got caught on something and is the main reason why I do not take these outside of the house, let alone away from my workspace. There is no strain relief on the headphone jack which is just plain ridiculous. Even $5 earbuds have some sort of strain relief.
In the earcup housing itself, the wires, just like the exterior cable, are extremely thin...I'm talking about Apple Earbud thin, no joke. The same copper brown and red wires found in the Apple Earbuds are in the HD238's cable.
The earpads are removable/replaceable so that's a nice feature of the HD238. They are secured with a very brittle plastic piece along the outer base of the earpad. If one decides to remove the earpad, there is a high probability that it will crack upon removal. Despite the cracked plastic, the earpads still fit securely back in place.
I have no idea why, but the left driver of my HD238 died after 6 months. Luckily Sennheiser's warranty still covers the HD238 (NOT the HD239 which is odd), and I got it replaced for free (well I had to pay $10 for shipping). It would not be surprising the problem had to do with the thin cabling in the earcup.
Being able to fold flat on a surface (via the swivel earcups), the HD238 is a semi-portable headphone, in my opinion. I would prefer a collapsable headphone (one that uses a hinge to fold), but folding flat should suffice for some. This kind of feature allows one to simply slip the HD238 into his/her backpack in a vertical position without having to worry about it breaking. Storing it in the provided carrying pouch might be a good idea so that the cable does not tangle.
Sound As summarized in the Pros/Cons, the HD238 is a bassy headphone (not surprisingly given its price point), with rolled-off highs. I do not have much experience with < $100 headphones, so my description of the HD238's sound may not be totally accurate. My observations have been mostly with my the Audirvana app on my Macbook with a FiiO E7. Most test tracks used were in FLAC format, some were MP3 (low and high bitrates).
The bass is the most prominent sound of the HD238, being pretty fat compared to rest of the sound spectrum. There is good bass extension, better than my Shure SRH940, and much punchier mid-bass as well. Overall the lows have a nice warmth to them. For electronic and synthpop music genres, these sound great!
The mids seem laid-back compared to the lows and highs. The mids are pretty good as a whole, but I suppose they suffer from the infamous Sennheiser veil. Male vocals and pianos in particular sound pretty decent. Electric guitars in rock tracks just seem...off because it is very laid-back and not very engaging. Similarly, female vocals and upper-mids in general seem off. I'll say the mids are passable (meaning they are listenable for most music genres).
Being rolled-off, the treble extension is not very good. The highs are not sibilant on the other hand, which is good since my ears are sensitive to such harsh ssssounds. That being said, just as the electric guitars sounded off, the snare drums and cymbals in rock tracks do not sound very good. Let's just say the HD238 lacks the kind of sparkle sound.
Being an open-back headphone, the HD238 naturally has a spacious sound stage. It is definitely wider than my Sennheiser CX-300 and the instrument separation is better too. Though my Shure SRH940 has a larger-than-normal soundstage for a closed-back headphone, they are only slightly better than the HD238, which surprised me considering the $250 price difference.
Ambidextrous/Morkva - In
Carly Rae Jepsen - Call Me Maybe (yes I listen to this song)
GACKT - Mizérable
HIZAKI - Mizerable
Killer Tracks - Paradise Awaits
Illness Sickness - Anything But Postrock
Little People - Basique
Massive Attack - Teardrop
MC Jin - 識講唔識睇
Moi dix Mois - D-SECT
The Track Team - Legend Of Korra Main Theme
Versailles - MASQUERADE
Concluding Thoughts If you're looking for a fun-sounding, bassy headphone, I would highly recommend the HD238 considering it can be found for under $60 nowadays, perhaps even less now that it is a discontinued model. You won't find audio perfection with these, but I would say they are pretty darn good for its price. These are very forgiving headphones, so I think they would compliment the needs for today's average consumer given they listen to pop, hip-hop, and/or contemporary R&B songs from the iTunes Store.
I paid 25 bucks for this phone, which makes it stupidly good value. Best Bang for the buck phone. Quite comfy so you can use it for quite a long time. Sounds is quite awesome, not 200$ awesome sound but for less than 50$, it is really great sound. Bass is quite strong, not so boomy and it is actually quite well defined. Mid not solid but quite good. Well, it has Sennheiser house sound, dark, bit veiled, strong bass, and laid back ... I'm bit love the coloring of Audio Technica so not really my cup of tea, but I can live with it for a while. I may choose phone this over es7 though. Overall, it sounds good, does nothing wrong, and very cheap.