Koss KPH40 Utility Review/Impressions
Jul 27, 2022 at 2:24 AM Post #46 of 93
I've put yaxi pads on all. That alone doesn't make porta pros and KPH40 sound the same. But put yaxis on all and then test them on the same headband, they'll sound the same.

I'm afraid I don't agree with this. As someone who has done just that, I find that there is a noticeable difference between PortaPro and KPH40 even when on the same headbands.
Jul 27, 2022 at 3:30 AM Post #47 of 93
I'm afraid I don't agree with this. As someone who has done just that, I find that there is a noticeable difference between PortaPro and KPH40 even when on the same headbands.
I should clarify that I'm talking about KPH40 and Porta Pro Utility drivers. I put the them both on KPH40 bands with Yaxi pads and they sounded the same to me.

I have put the original porta pro driver with Yaxis on the KPH40 band too, but haven't A/B tested that with the others. However, I do expect that to sound slightly different as it has a different shaped driver housing to the KPH40 and Porta Pro Utility.
Sep 10, 2022 at 1:53 AM Post #50 of 93
Crinacle recently measured the KPH40 and KPH30i. Putting those here along with other Koss squiggly lines.


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Sep 10, 2022 at 1:40 PM Post #52 of 93
From what I gather there are 4 different variations of the Koss 60ohm driver currently available. You have the original porta pro drivers, found in regular porta pros, kph30i, sporta pros, and KSC35s. Then you have the utility series drivers in the utility porta pros and the kph40i. Next you have the titanium versions which as far as I can gather there are two variations of. The KSC 75 (with its unique back) and the drivers found in the ktxpro1 and the UR40’s. The last two have the same backs as the regular porta pros. I own the regular porta pros, sporta pros, clear kph30i and kph40i. I have Yaxi pads on all but the sporta pros (I put the kph40 pads on those as they are slightly thicker then the stock ones) and I like the sound of those pads better on them. Next one I get will be the ktxpro1’s which I plan to re cable and putting on a parts express band. The band on the ktxpro1 is apparently weird in the way the cups articulate so no one uses them. I’m curious about them because they are different and cheap. I’m also going to get a pair of KSC 75s which I’m not expecting I will like, because I don’t like bright headphones. At that point I should have all four variations of drivers to compare. Right now my favorite two are the 30i and 40i. The 30i seem to have better soundstage to me then the others I own. Probably just due to how that particular band and cups interacts with my ears.
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Sep 12, 2022 at 5:30 AM Post #53 of 93
Alright, on a warm/super warm/smooth-dark source, the Clear's have the edge, but otherwise they're too piercing. KPH40 is more flexible, and as detailed, but pair them with a super warm source and it's like you're in a torchlit cavern, watching the firelight play across things.

So the 40's still win, because by default they're better. The 30i Clear's are an oddity... that foam was there for a reason. But if you can get them working for you... amazing.
I have them on the MF02s right now, and that's where they'll stay. Amazing, just amazing.
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Sep 13, 2022 at 11:00 PM Post #55 of 93
Nov 8, 2022 at 4:55 PM Post #57 of 93
Jan 13, 2023 at 11:27 AM Post #60 of 93
I 2nd the KPH40

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