Koss KSC75

I was dubious about whether to post this in the PortaPro thread or another thread, but I feel that the KSC75 are deserving of their own little space in the cloud.

Here is my review of them…

(as always, this is available in English and Spanish on my blog)

Koss KSC75

Many claim audiophile sound at a low cost but there are few that really earn that reputation. Koss has earned it and deserves it.

In the low price bracket, Koss has certain models that are legendary, offering sound that no one would expect from something so cheap. Two of the most famous of these are probably the PortaPro and the KSC75.

I have in my hands the KSC75 and I can only say what so many others have already said, they have no right to sound so good for so little.

I have the PortaPro for a while now, although I haven’t reviewed them (maybe I will soon because they deserve it), but I hadn’t heard the KSC75 until recently when I found them on Amazon for less than 20€.

Honestly, I knew they were well praised, although many prefer the PortaPro, but I didn’t purchase them with the intention of using them as is, my intention was to modify them and use them in a project I have going on (more about that another day). However, only after trying them out for the first time, I was already blown away by their sound.

As some may know, in Murcia (where I live) it is very hot in summer, which means I always move over to IEMs when I really prefer over ear headphones. It’s true that I find IEMs more uncomfortable but I would rather have a slight discomfort than have 2 wet sponges strapped to my head (which is the case with Beyer and Senn). Even with air-con, I still sweat, so IEMs it is.

Why am I saying this? Well, because the KSC75 are an alternative that I have now found and would never have thought to be comfortable (I remember clip-on’s from decades ago and the red ears in exchange).

But let’s break it down…

Build and Comfort…

As I just said, I thought I would hate the clip style of the Koss but I was quite surprised when I put them on for the first time and ended up listening to them for hours without discomfort. Once on my ears, it was like not wearing anything at all, at least in my case. In fact, the first time I stood up I nearly dragged everything off the desk with me.

In regards to build, well, this is not something that is a strong point. They are built completely of plastic, pretty bad plastic at that, and finished in a tacky silver colour that screams “old and cheap”. Which they are. Introduced in 2004, that’s makes them over 16 years old, but they are still 20 years younger than the PortaPro. In fact, I think that this retro look has become a trade mark of Koss and anyone that moves around in the high end headphone world has come to accept it. Koss probably make one of very few 20€, cheap and plastic headphones that are not laughed at by owners of headphones that cost 200 times more.

But respect doesn’t change the fact that they don’t boast a lot of build quality. The don’t look like they would take any abuse, nor are they known to, but again, they are 20€, thats why some people claim to be on their 20th pair of KSC75’s.

The cables are fixed, with no stress relief, and the housing is actually the driver. The supports are basically made of bent wire covered in plastic and there is not a single screw or drop of glue in the whole build. Nothing could be more simple (or tacky).


All of what I have said in the previous paragraphs is forgiven as soon as play is pressed.

Let me be clear, I am not saying that the KSC75 are “giant killers”, a denomination that is used more and more lately in reviews of the latest cheap releases, I am just saying that they have great sound, even without considering the price.

If you have tried the Port Pro’s, the KSC75 in comparison are a little brighter, with less bass, which loses a bit of that darkness found in the Port Pro’s. In reality, this seems to be due to the fact that although they use the same drivers, the ones found in the KSC75 are covered in titanium, changing the sound signature slightly. It is also due to the fact that they are resting on your ears, rather than being pressed against your ears by the means of a band like on the Porta Pro, which causes a loss of bass but creates a greater feeling of openness and space. It is like having two small speakers hanging at the side of your ears. There are people that prefer to modify them to use a headband, increasing the bass a little, but more on mods another day (there are lots).

I say that they have less bass than the Porta Pro but it is not a lack of bass, at least in my opinion. If you like very present bass then maybe you would be interested in some of the mods available but personally I find them well balanced in regards to the other frequencies (although I did bend the clips to bring the drivers slightly closer).

As far as the quality of bass, it is well defined, with good detail and they are capable of not losing definition even in difficult passages. Listening to songs like “Teen Town” by Jaco Pastorious, each note is detailed and clear. “Black Muse” by Prince, a song that can be overwhelming in bass and lower mids, they again deal with it well, allowing the bass line to be followed and appreciate the details of it, something that can be difficult on many headphones due to the way it is recorded.

In songs with artificial bass, such as “Bury A Friend” by Billie Eilish, they don’t feel congested and don’t seem to bleed into the mids at all that I can hear. In a song where the bass is more saturated due to effects, like “Bombtrack” by Rage Against The Machine, they again stay coherent and allow the bass of Tim Commerford to come through without issue, although in this specific song I did miss a little more warmth in the bass (for my personal taste).

Moving on to mids, again I find myself without complaints. It is true that these are not an HD6XX as far as voices go, but they do perform very well, presenting clear voices, well defined and with the warmth necessary to enjoy the majority of the music I listen to. In fact, I say they are not an HD6XX as far as mids are concerned, but I would venture to say that they actually perform better as far as space and placement is concerned.

Acoustic guitars, Spanish guitars and other acoustic stringed instruments, have the life and body they need. Again, they are not perfect, but they are a lot closer to perfection than disaster. I really enjoyed listening to the intro to “Diamonds on the Soles of Her Shoes” by Paul Simon, with other acoustic songs sounding just as good, except maybe for the treble on some occasions.

And that leads me to the treble…

The treble is likely my least favourite part of these earphones. It’s not that treble is bad, far from it, but they do exhibit a little more sibilance than I prefer on occasions. It is not an exaggerated sibilance, if the song is not sibilant then the KSC75 do not create it of their own accord, but they don’t eliminate it either. In songs like “Only Time” by Enya or “Hope Is A Dangerous Thing” by Lana Del Rey, the “S” can be a little more present than needed. It is true that these songs have a present sibilance on most headphones and speakers, so I do not consider it a fault, I would just prefer a little more attenuation for my personal taste.

Image and Soundstage…

Once again the KSC75 defend themselves very well. It is difficult to make direct comparisons as there are not many options that have a similar clip on style, however, in comparison to the majority of IEMs that I have listened to, the Koss have a much wider soundstage due to the way that you wear them, allowing a more open and spacious sound. It is not the widest soundstage I have heard but it is still surprising for something at this price.

I said before that they have a wider soundstage and better imaging than the HD6XX, and I maintain this. The HD6XX position the images well to the left, centre and right, but there isn’t much transition between those points. The KSC75 seem to resolve this transition better, giving a better positioning as things move from left to right, as is the case of the song “Letter” by Yosi Horikawa.


It is true that I expected a lot from the KSC75 after reading so many good reviews and also owning the Porta Pro, but I didn’t expect this much.

I again repeat that I wouldn’t consider these “giant killers” (I really don’t like that denomination) because I think that there are a thousand reasons why someone would choose other options that cost 10, 20 or 2000 times more than these. However, for someone who is a lover of music and enjoys listening to it with quality sound, I can totally understand if that person decides that these are the only thing he needs to be happy (well, maybe he would need various sets if he wants to be happy for a long time).

They are not pretty, they are not well built (although I have seen worse) and they may be uncomfortable for those that don’t like the clip on style (I thought I was one of them until I tried these). But these earphones are not to impress friends and acquaintances, showing off your beautiful headphones made of wood and silver, these are just for enjoyment.

If I were to see someone who is relaxing, listening to their favourite music and simply enjoying the KSC75, I would understand that they are a person who is just happy with good sound.

As I said at the start of the review, I bought these earphones for a project, however, after enjoying them for these past few weeks, I already have another set on the way to leave them stock. For 20€, these are something that any true music lover should have at home.


Great review!

I’ve heard of these as alternatives to the Porta Pros, but this is the first time that I’ve read any details to the differences in sound. Excellent job.

I may have to order a pair for myself.



Great review!

Been using a pair of KSC 75s for years and they punch well above their price. I paid $12
for my last pair. They’re also great during the summer when it’s too hot to wear
over-ear headphones. IMHO, they faithfully honor the music and err by ommision rather
than commission. The wires are delicate though and can break easily.


A top review @SenyorC

I prefer the 75’s over all budget Koss
It takes a bit of adjusting the clips and the Yaxi pads help with fit and comfort. I even can wear glasses with it. As long the sidearms are thin like on classic RayBan ones.

Thank you for taking the time and the effort you put in telling us about this little gem.


Really great review @SenyorC. Really easy to follow and full of common sense. Really down to earth and honest. I like this review very much. Great read.


Thanks for writing this thoughtful review. These are a favorite of mine when I’m out walking.


Excellent review, @SenyorC. I may have to try them. They seem to be a lot less fiddly than the much more expensive Koss KDE 250 that I reviewed from Drop. I’ve been tempted by them before, but like the bass and range of the Porta Pro.

Have you tried YAXI pads with them? Or does that reduce the bass further?


Although it is hard to believe, I have had the PortaPro’s for a year or more, and now have two sets of KSC75’s and have not yet purchased or tried Yaxi Pads!

(hangs head in shame)


Gotta get on buying those Yaxi’s, although they make less of a sound difference for the KSC75 as they do for the Porta Pro’s.


Can anyone advise on the comfort combination of yaxi pads with the KSC75s? The pads are more expensive than the headphones… :man_facepalming:

The additional surface area that covers your ear makes it more comfortable to me. I also find the Parts Express headband to make it more comfortable and user-friendly compared to the standard clips. Well worth it to me.


Thanks - may have to give them a go. Could do with having someone in the UK act as a distributor as I’m sure it would help when someone like me only wants a single set but doesn’t want the postage to cost more than the pads.


That is one of the issues with Yaxi, they really don’t have any distributors (at least here in Europe).

You can get them on Amazon now and again but it is usually more expensive than buying direct from Yaxi.

You bet. I could see how that makes it less attractive. The KSC75 with Yaxi is an awesome setup and could probably go toe to toe with most headphones up to the price of the HD58X (USD 150).


I got a sporta pro headband for my set.


thanks again… did you notice any sound different with the Taxi pads?

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Yes, Yaxi is my preferred compared to stock, quarter mod, and leather cushion pads.

To me, the Yaxi provides improved tonality (elevated bass, slightly smoother treble), clarity, openness.

If you want improved bass or a V-curve fun sound, you might want to consider the leather cushion pads which have a good seal and increased distance from the ear.

Please see US links below (they may be offered in the UK). I haven’t tried the Senn replacement pads, but they may provide some/nearly all of the Yaxi qualities. Good luck.



Thank you - smoother treble and a bit more bass weight is exactly what I think the KSC75s need… so it sounds like they would be a good choice. I may even have some of those pads on an old pair of Senn noise cancelling headphones somewhere. I didn’t realise they would fit!

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You bet, even better if you have old Senn pads to re-purpose! I recommend the quarter mod also which gave me good results for zero cost (for the UK, we can call it the pence mod!).


Mainly comfort on the KSC75, some think it helps… if it does its slight, unlike the porta pro which makes a bigger difference.

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