Koss Porta Pro Utility On-Ear Headphones, Detachable Interchangeable Cord System, Collapsible Design, Stealth Grey

Owned these many years ago and remember them being an excellent sounding headphone. They were not in the best of condition after years of use so decided to purchase a new pair. My memory did not fail me. The Porta Pro is still a fantastic sounding headphone for this price. In fact, I would compare them to models costing 4 times as much. One caveat is you have to like “on the ear” open sounding headphones. If you prefer an isolated “between your ears” sound these are not for you. Any loud outside noise will probably be noticeable. I prefer the “outside of your head” sound that these produce. The music floats just outside your ears much like listening to room speakers. The frequency range seems to be quite accurate. Even though the earpieces rest on the ears and not around, the bass is punchy, well defined, and musical with no added boom. The midrange has great detail and the higher frequencies may be a bit rolled off, but are very easy on the ears and do not produce audio fatigue. The Porta Pros, despite the low price are more than adequate for focused, critical listening. They are light and not sturdily built and should be handled with reasonable care. Highly recommended.

I have owned Koss headphones since the mid 70's...never found anything that would surpass my original Pro4AA's or my Pro4AAA's.My 2nd generation Pro4S I purchased a few months ago were more comfortable than the predecessors due to cup shape.and weight. The new Porta Pro Utility are the most comfortable yet being On Ear vs Over Ear but the sound is Perfect! Very little deep bass loss due to On Ear and extremely light! I wish I'd bought them earlier. I especially like the Modular design using the optional USB-C cable with the integral DAC circuit for my Samsung A54 phone which has no separate headphone jack!Well Done KOSS!!!

I have had these for all of 3 hours, so take it for what it is. first impression. as other reviewers commented. the wires out of the cans seem thin and weak. the sound lacks "full" midrange and highs. plenty of bass. I was surprised at the cable. thought it was 3.5mm to 3.5 mm. its not. one end of the cable is 2.5mm and the other end is 3.5 mm. this was important to me because I have a lot of 3.5 to 3.5 mm audio cables of all lengths laying around and was planning on swapping for a longer cable. I have had KOSS Porta Pro's in the past and I sort of remember them being made better, and sounding better, which is why I bought these.

So PortaPros in general are fine. Decent sound quality and very good for portability. Most portapros are a bit flimsy, but you can get a year or 2 out of them. These particular portapros failed after 2 months of completely normal use. They snapped in 3 different places ( the two headband pieces and one of the ears). Usually the points of failure are the joints, but on these the extraordinarily cheap plastic snapped clean through. If you're gonna get a pair of headphones, respect yourself more and get different ones.

Definitely had high hopes for this one, the sound quality is pretty good for the price. After daily use for 1 month (+10 days out of the return window), this headset has already broken. 2 stars for the sound quality, 1 star for the durability. Do not recommend.

The Koss Porta Pro Utility adds the flexibility to swap out cord lengths and add the ability for 2.5mm, 3.5mm, USB-C or Lightning DAC functions. This headphone is very light weight and open backed giving you the added safety of hearing your environment. The sound is rich and dynamic with the efficiency to be driven by just about anything you plug them into. My last Porta Pro pair was destroyed by a teething puppy and I'm happy that they are once back again and still the old friend I knew.

Edit: Koss contacted me! They are standing behind their product and replacing my unit; what more could I ask for? Thanks to Mike at Koss I'll hopefully have a set without a headband defect. I will update this review appropriately if that is the case!In short:Good:Super portable (seriously smaller than the earcups of my daily drivers when hooked)Sounds great with a pad rollPorta Pro band wont fly off of your head while you exerciseBad:Questionable changes to the bandNeeds thicker pads out of the box if they're trying to make the (imo positive) sound changes found in the 40 uniform in the PPUOut of the box... I wasn't entirely sure. There is a slight boxiness to the soundstage, and a slight loss of separation compared to the KPH40. Initially I thought that it could be some reflection from the plastic frame (compared to the lack of anything surrounding the KPH40 drivers) but... it seems to be the clamp force. The drivers are being pushed just.. slightly closer to your ears. And that is all it takes to make them sound inferior to the 40's on first glance.I tried yaxis with the 40's, didn't like it. Tried them with the PPU, and now they basically sound just like the 40's (though I still perceive a slight elevation in sub bass and mid bass).Now on to a real issue.. They used the same teflon coating on this band, that they did on the 40, and that was a MISTAKE, in my opinion. The sliders are literally scraping the teflon off of the band, leaving an unsightly mark. The worst part about this is that the inconvenience isn't rewarded at all.. they do not slide nearly as smoothly as the original Porta Pro did, nor any of its subsequent variants. As a reference I have used them maybe 4 hours total, and Adjusted them 4 times (once per session)I'm going to contact Koss and see what they say about the band damaging itself... Unfortunately I expect that if it's not an isolated defect, a replacement band will do the same thing. If it DOES end up being a defect, and not just a design flaw, I'll mention it here and add a star.