I have a Koss KPH40i gripe & some early praise

My new girlfriend, unlike past ones, likes good music & hifi gear. So wanting to share in good listening sessions I purchased 2 Koss KPH40i. First listening impressions, streaming Amazon Music via Bluetooth in LDAC to my iFi Zen Blue V2 on to my Xduoo TA26 listening to Holst: The Planets, is wow, with the volume knob around 12:30 to 1:00. Plugged the KPH40i into the Topping A70 Pro, volume at -17db & I’m happy. Haven’t tried my Singxer SA-1 yet being it’s not hooked up at the moment. Im told these scale but I need more time listening to them on my various amps.

The gripe I have is that it took me at least 20 minutes before I realized I had several 3.5mm to quarter inch adapters readily available. The KPH40i doesn’t come with an adapter. The other issue was after fiddling with the first adapter I found for a few minutes that it just wouldn’t fit the 3.5mm terminationon the Koss. Ive got 4 or 5 quarter inch adapters but only 2 will fit the 3.5mm Koss cable termination.
Why not just make the far too short cable a 4.4 pentacon termination, or supply a female 3.5mm to male 1/4" TRS adapter for an extra $7 Koss? These $40 KPH40i sound way way better than my Samson SR850 in every regard. They might hold their own against my Beyer DT1990 Pros.
Prior to finding the 2 adapters that fit, I already ordered $120 worth of nice cables just to use with the KPH40i, which will allow me to run them balanced with a 4.4 pentacon termination or unbalanced with TRS adapters.


She’s a keeper!

Glad you and your new GF like the KPH40i. I love my set with everything from music, to movies, to using them while playing my Simmons SD600 eDrums.

I actually have two 1/8" to 1/4" adapters and they both fit and work fine with my set, thankfully. For the ones that would not work for you, would the plug just not seat all the way into the adapter properly? Just curious is all.

Glad the new cable investment is working out, the set it worth the extra investment imho. :headphones:

Exactly the issue. Not all adapters are the same, even if they’re supposed to be the same thing. The female end of some of them will not allow the 3.5mm tip to snap/lock in. The one’s that work have more space at the rim allowing the 3.5mm all the way in. I imagine the ones that don’t work are proprietary designs instead of universal designs.

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I have had the same issue with fitment on 1/4" adapters before, I like these ones from Ugreen because the face of the 3.5mm interface is flush: Amazon.com

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I discovered my KPH40i do need the grip of a nice solid state amp to retain control of the low end on the dynamic crescendos that contain a lot of bass in them. They were distorting on my TA26 in this circumstance, even at just 10:30 on the volume knob.

Edit: On the A70 Pro there isn’t any such distortion at normal listening levels.

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I noticed the same, can be source dependent. Tested mine about a week ago hooked up to my PS4 controller for a late night viewing of Top Gun: Maverick. While this source is usually fine for powering my Senn HD598cs cans, it made the KPH40i’s sound…“thin” and underwhelming. In comparison, they sing beautifully on my Magni Heretic headphone amp. This is how I mainly drive them nowadays and have been using them as my daily driver for some time now. :headphones:

On another note, I now realize that the detachable cable that comes the KPH40i, although looking like a 4.4 pentacon, it isn’t & it is something far smaller than a 4.4 pentacon so the cables I bought, 4.4 male to 4.4 male, will not work.