Man, these sound really good to me. With the Porta Pro and KPH30i, I liked the bass, but I wished there was bit more mid and treble. The bass was good for some songs, but sometimes it would overpower things like vocals. The KSC75 has very pleasing mids and treble. It does not have extension like my ATH-AD900x, but it is not as shouty or piercing either. However, bass performance is worse than my ATH-AD900x, which really disappointed me. Sub-bass suffers even more than in the Porta Pro, and there generally is no sense of energy or fullness to the bass. Good headphones, but just not for me.
Then there is this thing – the KTXPRO1. In short, its sound signature is probably some where between the KPH30i and KSC75. Ranking from darkest to brightest, I would say Porta Pro, KPH30i, KTXPRO1, KSC75. In my opinion, the KTXPRO1 has the most balanced signature of the Koss 60 ohm lineup.
That begs the question: if these sound good like the other Koss 60-ohm headphones, why is there barely any info on these compared to the Porta Pro, KSC75, KPH30i, or even the UR40? If anything, the KTXPRO1 is deserving of its obscurity because it has possibly the worst fit of any headphone out there. Definitely the worst I have tried, and I have in the past tried some cheap Chinese goods that had really questionable fitment. I don’t blame anyone who instantly returns these headphones. It took me a full day to get used to the awkward fitment, and it honestly was very frustrating.
Despite the frustrating ergonomics, I really like the sound. I put up with the fit because I love the sound. Because I love the sound, I am writing these set of impressions right now. I want these headphones to get more recognition because I think they truly are as good or better than the other Koss depending on your preferences.
So let’s get started:
As I said before, ranking from darkest to brightest, I would say Porta Pro, KPH30i, KTXPRO1, KSC75. These cans have a slightly-warm neutral/v-shaped (my ears are not accurate enough to tell) tone that I feel very well balances bass, mids, and treble. Sometimes it feels a bit tinny or shrill, but it’s more of an instinctual take rather than one from observation.
The bass quantity and punch are nowhere near as much as that of the Porta Pro, but there still is some impact and volume to mid/high bass. I’d say it has notably better bass impact than the AD900x, which doesn’t say much other than it is adequate. Like other 60-ohm Koss, sub-bass is weak, but it is there. Just there. As I said in the intro, I sometimes felt Porta Pro bass would overpower mids. The bass didn’t bleed in, per say, but emphasis on bass made stuff like vocals feel slightly recessed. With the KTXPRO1, I never felt bass got in the way of other frequencies. Nor was it ever lacking – contrabass and cellos are full-bodied and produce their characteristic rumble, bass drum has appropriate kick, etc. With bass focused electronic music, a bass boosted signature can be fun, but I feel the KTXPRO1 renders the sound “just right.”
Mids seem to be a strong point for all the 60-ohm Koss – FR graphs often depict stuff like the Porta Pro and KSC75 having decently flat tuning in the mids. The KTXPRO1 is no exception. Melodies carry out very well, vocals at various pitch all sound smooth and natural, etc. As I stated before, bass does not get in the way of mids, so melodies in the mid frequencies stand out clearly. Mids are not forward like they are with the AD900x (a mid/treble focused can), but they never feel weak and recessed either.
Treble is alright overall. I feel it does not fair as well as the KSC75’s and definitely pales in comparison with the brilliance of the AD900x. The KTXPRO1’s treble is still adequate. In the Porta Pro, there is no real sense of air or energy in the trebles, but the KTXPRO1 can reproduce hihats with crispness and give violins, brass, chimes, and female vocals the edge that makes them so pleasing. I feel like there is better treble extension with the KTXPRO1 than with the Porta Pro, but not as much as a KSC75 would have. You’ll hear hiss in a recording that the Porta Pro can’t dream of picking up. Of the frequency ranges, I would say treble is the most lacking of them all. And yet, it’s not bad either. Just not remarkable.
I first would like to be frank and state I suck and judging stuff like resolution and what not. Nor do I fully grasp these concepts.
The KTXPRO1 handles rapid notes decently – drum rolls and such sound much more distinct with my AD900x, but they don’t exactly sound like a complete mess with the KTXPRO1. Resolution is alright too. Through various recordings, I don’t feel like it’s much worse than my AD900x if worse at all. I can easily hear pedal work on the piano, the rustling of pages, the grain in synthetic timbres that are grainy, the different kinds of strokes done with a jazz brush, etc.
I’m not fully sure, but I’d like to say it equals the capabilities of the other Koss 60-ohm headphones. For casual listening, the inabilities of the KTXPRO1 will not get in the way.
Soundstage and Imaging:
It is surprisingly expansive. Of all 4 headphones I have now, these have the most natural soundstage of them all. The difference voices do not clump up like they would in the Porta Pro or AD900x but are decently spaced out.
Through several full-orchestra pieces, I found the soundstage to be adequate. The piano in front is for sure in front and center. The strings a bit further back. The brass is clearly behind both piano and strings. And the timpani roars way off in the very back. I would say spacing is good, but the overall staging feels smaller-than-life.
With recordings of smaller groups or synthetic voices (e.g. electronic music), there seems to be appropriate spacing. My AD900x feels more intimate with stuff like jazz, but it also suffers from inappropriately-large soundstage with electronic music, possibly due to the treble tuning giving a sense of air. With the KTXPRO1, electronic voices seem to be an appropriate distance away from my head, slightly further away than where the drivers are in actuality.
With binaural stuff on YouTube and ASMR, it performs quite well. Haircuts, knocking, in the car, city buzz – all sounds good as it should.
I also tested with a video of some person whispering into a binaural mic (don’t judge, I swear I don’t listen to these things really) and… fuck. I swear I could have felt the warmth, humidity and puffs of air from aspirated consonants. Made me jump and throw the headphones down on the table. It was uncanny. With other headphones, it was much more apparent the sound came from headphones but the KTXPRO1… idk. The openness and lightweight of the headphone must have tricked me for a moment.
Imaging is weird. I feel like LR distinction is less obvious with the KTXPRO1 than with other headphones. Going through music with LR sweeps, it took some concentration for me to notice. Left only will still be left only, but a spectrum of center to left seems to be a bit nebulous. Even so, they haven’t given me issues with stuff like games, although I still prefer the imaging in my Porta Pro or AD900x.
Looks like a toy. Feels like a toy. The silver paint is pretty much toy-grade as well – rough and looks like it will chip easily. Plastic creaks quite a bit when I wiggle my ears or whatever. The driver housing has play on its swivel. The open-back grill is metal, and the silicone headband is pretty secure. What is nice is that the wire connecting to the drivers have some reinforcement to them. At least from Amazon reviews, it seems the KTXPRO1 lasts longer than the KSC75, so maybe these can be an alternative donor for titanium drivers. The cable also has a clunky volume slider at the Y connection. It works smoothly, but nothing special. There is some play in the slider, and people have reported it breaking rather quickly. The 3.5mm end is straight and is not as reinforced as other Koss connectors. Surprisingly, this came with a 1/4 inch adaptor that is near identical to the one that came with my FiiO K5 Pro.
Isolation and leakage:
It is definitely an open-back. More so than the other Koss, more so than my AD900x. In terms of isolation, it muffles slightly in comparison to my AD900x, but it is significantly more open than my Porta Pro and a little bit more than the KSC75, I think. Sound leakage is about as bad as it is with my AD900x – 65dB spl in is maybe 35dB spl according to my phone (which seems accurate enough).
Fitment and Comfort:
A diagram to visualize fitment.
Rant mode on.
Seriously Koss, what the flying fuck is this design. It completely ignores any idea of ergonomics. Before I get to the worst part (the driver fit), I want to at least say the silicone headband is comfortable, much like that of the KPH30i. But the driver mountingggggggggg FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF.
I spent a full hour trying to figure out what position was most comfortable. Turns out it is slightly forwards so that it doesn’t touch the helix. But coincidentally, this is also where the headphones sound the worst – muffled, boomy, treble recessed. Equally ironic, the clear and spacious sound comes out when I rest the cushions further back where it is the most awkward, uncomfortable, and unstable. This is where the center of the drivers are directly pointed towards my ear canals. Koss why do you hate your customers.
So the swivel for the drivers. It’s on one axis that is diagonal. So if you tilt the drivers together on the x axis to try and match the angle of your ears, they also tilt inwards on the y-axis when they should actually be tilting outwards. At least for me, this design puts all pressure on the upper portion of the antihelix of the pinna.
The cushions are inadequately thin and small. Circumference of the KTXPRO1 cushion is smaller than those of the Porta Pro and KSC75 cushions. Thickness is half. As a result they fail to distribute the pressure on the antihelix to other parts of the pinna. They don’t touch anything except the antihelix and helix. The extra openness in the front and underside of the ear probably contribute to the openness of the sound but man, this fitment is so awkward. Oh, forgot to mention that the small circumference of the pads mean that the driver casing rubs against the helix. Yup, that unsanded plastic edge.
Stability sucks. At least for me, my head is a bit too small, so the headband doesn’t have much tension on my head. Coupled with the low clamping force (even less than my AD900x) and sucky cushions, they slide off if I tilt my head forwards more that 30 degrees. Side-to-side motion is a no-no as well.
Rant mode off
Even though fitment sucks, I will say these aren’t too uncomfortable once I got used to the fit. In fact, these headphones cause the least amount of long-term discomfort out of any headphone I have tested (except the KSC75). You see, their lightness means no neck strain. The silicone headband gently resting on top of my head causes very negligible sense of pressure. The low clamping force means my ears are spared. Yes, even though the drivers press against the antihelix uncomfortably, the residual discomfort can easily be massaged out.
Having just switched back to my Porta Pro while going outside… whew. Yaxi pads feel good but I don’t remember them feeling like a mother’s sweet embrace on my ears. Going back to the KTXPRO1 when I arrived back home, I was reminded of how terrible they feel. The pad comfort between Porta Pro with Yaxi and the KTXPRO1 is heaven and hell.
To replace the pads, you need to take the driver casings off the swivel and then pry the driver out from the casing. Much like with other Koss 60-ohm headphones.
I don’t have an extra set of Yaxi pads, so I replaced the stock pads with stock Porta Pro cushions. The difference is comfort is actually larger than I expected. Because they are twice as thick, the Porta Pro cushions spread out the pressure a bit more. In addition, they extend beyond the casing so no more ouchie plastic.
So how did the sound change? Glad you asked, because I would like to know as well. I honestly can’t tell if it is placebo or real, but I feel like the sound is every so slightly more muffled. Maybe the bass response increased slightly. If there really is any change, it’s more or less negligible, especially considering the added comfort.
I have also tried Yaxi pads borrowed from my Porta Pro. No. Just No. They solve the comfort issue, but as I feared, they drastically change the sound. The signature becomes more V shaped. Bass is stronger, but with reduced clarity and added bloat. Mids don’t change and end up feeling recessed. Upper treble gets WAY louder. This makes stuff like chimes/triangles and hihats extra crisp and sharp… but that also means added sibilance. Soundstage gets worse, imaging becomes more distinct yet binary. Essentially, they start to sound like Porta Pros with a lot of treble. If a very V-shaped FR is your thing… I guess you may like this.
I have heard people mention using Plantronics cushions for the KSC75, so maybe it will also work better for the KTXPRO1.
Impressive sound, equally impressively terrible ergonomics. I truly love the sound of the KTXPRO1, so the level of discomfort they can cause is heartbreaking. As much as it pains me to wear them, I feel it would be even more heartbreaking to return them.
I want to keep them for a week longer before I make a final decision on whether or not to keep them. It’s only day 3, but I’m already sold on the sound. I just can’t find out if I can live with this fitment.
I can’t recommend them as “good” headphones, but they definitely are interesting ones to try if you’re curious. $20 on Amazon.