Koss UR 55 - Reviews
Pros: Low Price, soundstage, smooth treble, clean bass and mids, sturdy cable, vocals sound really good
Cons: Not worth your money if you don't mod, bass doesn't go deep, isolation, ugly
Well, I created an account just to review these. So here it goes:
I was looking for an inexpensive (<50$) portable pair after my incipio f38 and my JVC s400 broke down (these are ridiculously good headphones for the money by the way). I got these after I read tdockweiler's review and mod topic. Out of the box, these headphones were pretty mediocre next to the similarly priced headphones I mentioned above. They sounded muffled with muddy bass. So I performed the mod successfully. Removing the pads was easy thanks to my long fingernails (yuck), but the cheap screws made it a challenge to put the headphones back together. Furthermore, I can't seem to fully remove the cloth obstructing the driver, but that's a minor issue.
Well, I have to say that they sound a lot like my Grado sr60...with less bass. And that's a good thing because the Grado is not as portable, costs more and has an annoying cable. The treble is silky smooth (that's the selling point here because most headphones have sparkly/sibilant treble which makes me cringe), the mids are clear, the bass is very clean but a little shy for my taste. The soundstage is incredible and the overall level of detail is amazing for sub 50$ headphones. The vocal reproduction is outstanding for the price. It's superior in my opinion to the headphones mentioned above, but you sacrifice isolation and bass. I find them comfy, but the foam pads do make my ears sweat after 1 h of use. I think that the amount of clamping force is just right. The cable is fantastic: it's short (I don't see the point of long non-removable cables when you can buy an extension cord for a few bucks), it's tough and light.
EDIT: I had this headphone for weeks now and I have to say that I am still blown away by the overall performance. The bass seemed to open up after some burn-in and it is now on par with the Grado Sr60. The killer features are really the soundstage, vocal reproduction and speed. No other headphone in it's price range can compete with the Koss UR55 on these features, not even the Superlux hd 681 EVO. However, there are 4 drawbacks: 
- Noise isolation is non-existent.
- The foam ear-pads make my ears warm after 20 minutes.
- As with the Grado sr60, I wish that the bass would extend deeper. I feel like I am getting the mid-bass but not the deep-bass. Few headphones in the sub 50$ range reproduce deep bass anyway, so it's really a minor issue.
- They are ugly when the grill is removed. 
I miss these things. At one point I must have had three pairs and were what made me pick up the DJ100. I didn't find them anywhere near bass shy, but perhaps in the low bass. Sounded like they had a slight mid-bass hump. Based on memory, they have smooth treble, are close to being dark and had very good mids.
I stopped listening to them because the pads are kind of awkward. I need to try the HD-681 EVO. Had the HD-668B but hated it's V-shaped signature. For the price it was a steal though, but I prefer better mids and a little more warmth.
One other headphone in the $60 range that's quite good is the Beyerdynamic DT-235. Too bad it's supra-aural. You can mod it with over ear HD-202 pads, but then it has too much bass!
I remember when I was modding the UR-55 I felt it sounded better than even the Grado SR-80 as long as you removed the outer grill fabric.
Pros: Inexpensive ($35), Open Air, Light, Neutral, Decent bass response, Good detail
Cons: A little flimsy, kind of small, foam could have been nicer
Koss UR 55 Studio Pulse An inexpensive performer
There's a vast array of inexpensive headphones out there. Thousands of them. But every now and then, if you sample around, much like wine, you can fine something inexpensive that is actually pretty good. The Koss UR 55 Studio Pulse is a headphone that fits that description. I picked it up for $35 from Amazon (was on sale, goes on sale now and then, just watch for it if interested) because at a price like that, it doesn't matter. So I took a shot at it to see. I've seen some information out there on them, which is limited, so for the most part this was a shot in the dark. That's fine by me though, I like trying things. I wanted to see what kind of application an inexpensive headphone could be used for. Mainly though, I really wanted to find a decent headphone that had good imaging, was open to semi-open air, had a good frequency response and was inexpensive. Hard to find all that in a cheap little package. That's where the Koss UR 55 Studio Pulse comes in.
So a little summary to see if you're interested, in which case, the rest bellow is for you.
  1. Open-air
  2. Over-ear (but snug, so they're smallish)
  3. Soft pads (foam)
  4. Good sound stage
  5. Good extension both in highs and lows (can do bass well)
  6. Good for gaming, movies and music listening
  7. $35 on sale
What Comes In the Box:
View attachment
View attachment
The package is rather simple, it's very small when you first see it. The headphones are classed as over ear, but they're not very big, so they are over ear on normal and small ears, and snug at that, but on someone with wombat ears, these are likely going to be too small. There's no accessories or adapters. You simply get a set of headphones with an attached cord and the mandatory wasteful slips of paper that either advertise or tell you how not to strangle yourself with the cords.
  1. The headphone itself
  2. Paper junk and plastic packaging
  3. No accessories or adapters
Construction, Materials & Comfort:
The headphone is build of plastic with some metallic grills and a metal band within the headband, likely magnesium and/or aluminum. But you never really know. Might cause cancer, right? Regardless. The construction is actually kind of flimsy. Everything is tight and holds together, but the entire headphone feels very light almost toy-like. I've had mid-tier headphones that felt like that, so I didn't let it really sway me, but be prepared for that.
The foam pads are just foam. Nothing special. But also, not plastic or vinyl which is a plus in my mind. They're actually pretty comfortable. They don't clamp too much, so they're not too tight, and the pads fit over my ears and touch a little. Again, they're a little small, so these are not likely going to fit someone with old man ears that are huge like kites, har har. The headband has a memory foam that is within a vinyl type material that is nice and soft, not a foam that is exposed that will keep scent, so that's a plus.
The grills are simple. You can see into them. They're semi-open to open-air (depends how you define it I guess). Point is, they're open, so they leak and you can hear things around you. This is a good and bad thing depending on your needs and wants. I think it's a good thing and that's why I went for them, inexpensive open-air headphones to try. The style is not over the type nor completely bland. They look kind of nice.
The cord is very small and short and terminates into 3.5mm. I would have liked a longer cord. But inexpensive models don't tend to have all the bells and whistles so I can't really fault them for this.
A huge note about the headphone is size. They're not very big. I had to extend the headband extensions to get the ear cups down to my comfort zone around my ears. These are not going to fit on someone with a massive head and massive ears. Keep that in mind. I almost felt like they were kid sized. I've never had to "max" a headphone's extensions to wear them. So that sort of took me by surprise. Keep this in mind if interested in this headphone, they're not huge, they're not micro, they're smallish though.
View attachment
View attachment
View attachment
Sound Characteristics:
I wasn't expecting the world, nor did I expect absolute rubbish, so I had to just slide into them and see. I did not bother letting them pretend to burn in over a long period of time. They're $35 headphones. And I'm not in the camp of magic phenomenon anyways. I went straight to listening and put some time in. Played some tunes, watched some YouTube stuff in HD, played a movie, and then tried some gaming fun to see how they handle everything.
Quick summary for the impatient:
  1. Relatively neutral sound
  2. Clear treble that is not fatiguing
  3. Mids are solid
  4. Bass is actually good and can extend low with a bit of reverb
  5. Good sound stage, good imaging
  6. Good for listening to virtually any genre, good for movies, great for games
  7. Easy to drive
Music tested, from my trusty test-group that I tend to use on all headphones (all lossless), included: Ani Difranco (Acoustic, Female Vocals), Regina Spektor (Folk, Pop, Female Vocals), Euge Groove (Jazz, Bassy), Ludovico Einaudi (Classical, Piano), Keith Jarrett (Classical, Piano, Live Concert), The Cranberries (Pop, Female Vocals), Elton John (Classic Rock),  Avantasia (Metal, Fantasy), Buckethead (Alt. Metal), Rusko (Dubstep), Ephixa (Dubstep), JesusDied4DubStep (Dubstep), Robyn (EDM), BT (Trance, Techno), OceanLab (Trance, Techno).
Movie tested, Priest "2011".
Game(s) tested, Oblivion, Bad Company II, Star Craft II, Torchlight
Hardware tested included Sansa Fuze, Vivid Technologies V1 DAC/AMP, Matrix Cube DAC/AMP, Schiit Lyr, Auzentech Forte Soundcard.
Treble (Highs):
The highs of the UR55 are pretty good, they're not too bright, they don't fatigue me, and I didn't really have an issue with sibilance. There was some noise floor present, but that was likely due to my equipment, so I cannot say for sure. But then again, I don't expect a hiss-free inexpensive headphone. The detail was pretty good, pretty clear sound. I felt that the highs sounded a little bit like there was a fog around them, so I'm guessing there was some odd spikes in the 5khz to 10khz range, both up and down, but likely a bump around 10khz compared to before it to get that edge sound to it. I could hear the flicks on guitar strings, cymbals sounded right and were not too harsh or hot, and there was a good snap but not enough to punch you deaf.
The mids stand out as being the main sound you hear (as it should be, really). I felt like the mids were full and gave you a good sense of body. Rock sounded good. Voice had some body to it. Instruments had a good solid sound behind them. The mids were pretty clear with some detail, but I also felt at times like there was a touch of congestion which may be due to the driver being a little slow, so I'm not quite sure there. It was clear most of the time though and pleasant to listen to.  Just from ear, I think it may be flat from around 2khz to about 500hz or so perhaps. It's a good sound.
Lows (Bass):
The mid-bass definitely comes through, which is usually a hard thing to get in an inexpensive headphone, especially open-air. Usually they're bass light, but this is not a bass light headphone. It's not a bass monster, but it simply has good impact and can manage low tones that reverb and sound good for moments where bass becomes important. It makes it have a relatively warm sound, and richens it up. It was nice to have some rumble in games and movies, and of course, during music that called for some tones down there. Cello and bass sounded good. Explosions were nice and rumbly. Again, the bass doesn't pound you down, it's not a subwhoofer, but it definitely is more present than the likes of other popular headphones that are similar (to give you an idea, it sounded quite bassier than the AD700, so in a very good way).
There is no isolation, it's open/semi-open. Leaking will occur both ways.
The idea of getting an open-air headphone is for the benefit of the usual decent sound stage and the UR55 delivered there nicely. Sound stage is pretty good. Lots of nice separation, not cramped feeling at all. Music playback was nice, you were in a room, not a closet. Movies had a nice amount of space. Games sounded good, great positioning and imaging was good. The sound stage is not overly expansive to the point of artificial sounding, but it's not a tiny little cramped space either. Overall a good soundstage for it's type and cost.
Gaming & Movies:
Ideally, I was looking for an inexpensive headphone to review that was good for games and movies, basically, an inexpensive alternative to the popular, and highly over-rated, AD700. And I was pleasantly surprised to find a $35 alternative that has a good sound stage, good imaging and some bass, all at nearly a third of the cost of the aforementioned. Games sounded good, the sound was full and immersive, not hallow sounding. Positioning was good, and you could navigate with sound as you should be able to with surround effects. Movies also benefited from this and it was nice to hear some rumble and good imaging. Combine some good comfort and you have yourself a very inexpensive good-for-gaming headphone that also can be used for movies.
Closing Thoughts:
View attachment
The UR55 is a smallish headphone with foam cups with a good enough soundstage for gaming and enough bass to satisfy genres that call for it, making it quite a decent headphone for it's humble $35 price tag. I could only really fault the cord for being too short and tiny diameter, and overall the headphone's size was relatively small, making me max it out to wear it in my comfort zone. But beyond that, it had surprisingly good full bodied sound with some detail to it. I was impressed enough to recommend it over the AD700 for gaming and general music listening. But it doesn't quite stack up to the other alternative, the Fischer Audio FA-011 (which I think is the best budget headphone for games, movies and music that is open-air and bass capable in the $100ish range). But this little guy competes rather well with the $100 tier headphones, even though it's only $35 on sale. If you have a friend, loved one, or just yourself, looking for an inexpensive headphone for these applications, especially a gaming headphone, this would be a good route to take. I didn't keep the headphone myself, as I have no need, but it was fun to try it out and put it up against some far more heralded headphones and see if $35 could stand in the crowd so to speak, and I felt that it did quite well.
Great headphone for rock and jazz, also good for acoustic and indie or folk. It performs decently for electronic musics like Trance, Dance and Dub (not quite a bass titan). So it can handle most genres pretty well. It's not too bright, and it's not anemic.
View attachment
View attachment
Very best,
Yea, they were about the diameter of the L-cush pads roughly, but just a tad more in that you could put your ears in them (unlike Lcush pads).
Nice review and I agree with it. Loved these headphones for the price I paid when I had them. The sound clears up and is less congested when the grill OR the fabric backing is removed. I don't suggest it unless you have money to spare. Maybe koss removed it's fabric backing behind the grill? They even have a closed pair called the UR-50.
The pads are held on by adhesive under the plastic backing of the pad. You take a tiny flat blade or screwdriver and pry it up. They're sticky enough to be able to reuse. They don't work with any other headphones. Here's my old mod:
I don't suggest the mod due to it being almost impossible to reverse.
Thanks for the review @MalVeauX I know you also reviewed the Samson SR850, vs. these, which offer the best SQ overall?
Pros: Cheap, Bass, Soundstage, Imaging, Great Mids
Cons: Could be more comfortable, bass bloated and slightly muffled mids without mod (congestion)
This is a review of a fully modded UR-55. Out of the box it's good, but not great. Without the mod the mids are very slightly muffled with some songs and the bass can be bloated. All this is caused by the grill and fabric behind it. I'm 100% sure of this since I had two pairs to test the differences!
When modded and these two things are removed the sound improvements are just amazing. Nothing subtle here in any way. Everything is more clear, the bass is not bloated and more controlled and the soundstage is much better. I think this is a driver that needs a lot of air to sound it's best.
Basically the only way I can describe the signature is just something that sounds "just right" to my ears. It'd be neutral if it wasn't for that slight bass boost to make them a bit more fun to listen to. The mids don't get drowned out and vocals are crystal clear at all times. The highs may be very slightly rolled off, but I find this a good thing.
The level of detail is quite high, but not as high as the Koss Pro DJ100. I think once modded these would make a PERFECT budget gaming headphone. No joke! They're that good. Strangely these are one of the first $50 headphones i've ever had where 128kbps MP3 files sounded like garbage and I could even hear recording hiss in some of my songs.
Before the mod, my Maxell DHP-II was better, but now these are my favorite un-amped headphone under $80. I actually bought the Shure SRH-440 and they lost out to these (I do love the SRH-840 though). The only thing that's comparable in sound that I own (under $100 and un-amped) is my modded Grado SR-80. The sound on those is slightly more clear and it's a brighter headphone, but does lose out compared to the UR-55 in some areas. Modded UR-55 has more bass, a better soundstage and imaging and better comfort. Mids may be slightly more forward on the SR-80. The SR-80 thought is still probably better for metal, but for $50 it's hard to complain!
More people should try this mod. This is really one hidden gem in the headphone world. It's only a slightly above average headphone without the mod.
Anyone who loves the Porta Pro or KSC75 should love this headphone when modded!
And what kind of mod are you talking about in this review?