Quirky looks. Lightweight build. And they feel low budget (well, they are). The Koss Porta Pros are nothing if not distinctive. 

The thing is, I knew all of that when I decided to review them. The question was what they sounded like.  I was expecting passable – there must be a reason they’ve been in constant production since the early 1980s. I just wasn’t expecting the genuinely huge grin that spread across my face when I plugged them in. I sank into the music, an initial listen turning into an extended session. Which happened a number of times.   

No they’re not giant killers. The £99 Grado SR80X on-ear headphones, also in for review, do most things better than the Porta Pros. If you want a no-fuss pair of headphones that give genuine musical enjoyment then read on though, the Koss may be just what you’re looking for. And retro style comes back in fashion at some point, right?

Timeline & versions

A little background. Koss is named after its founder, John C Koss, who in 1958 produced what is claimed to be the world’s first stereo headphones, the SP/3. Over the years a positive flood of new models ensued – see here for the lowdown – with the introduction of the Porta Pro in 1984 a conspicuous moment. Whilst it has been developed over the years the Porta Pro’s basic form hasn’t changed. 

The current Porta Pro lineup has several variations. The Classic is the one we’re reviewing here. List price is £45 / US$50 / €50. Get it for less if you shop around.

Koss’ first headphone, the SP/3

The Wireless version is largely devoid of wires (a short stub cord houses the Bluetooth electronics & battery). The Mic/Remote version is for making phone calls as well as listening to music. And the Porta Pro Utility has a detachable cable. As standard you get a 3.5mm cable. Optional USB-C or Lightning cords (inc DAC) are available for connecting directly to your phone (they’re much cheaper if bought with the headphones). Finally alternative colour schemes are available, although personally I don’t think I’ll be rocking the beige or gold Porta Pros any time soon (more a comment on me than the headphones).  

Key features

A thin steel headband leads to two plastic housings for the drivers (one driver per side). The housing looks strange, reminding me of musical notation. Let’s just say it’s distinctive. It’s also hinged to fold the Porta Pros down when on the go (a case to protect them when travelling is sensible). The headband expands in a simple manner to match the size of your head. Even my large head didn’t need it on maximum, so it should fit most people. 

A sliding button on each earpiece switches the headphones between firm and hard modes. I didn’t notice any difference, both are supremely comfortable. At 60g (+10g for the cable) the Porta Pros are so light you don’t really notice them on your head. Which is a key benefit, or am I the only person for whom headphone comfort is crucial?

Build quality is adequate at best; the Porta Pros feel flimsy in use so handle them carefully. But that’s why they’re so light, so comfortable and so inexpensive. A trade off I for one am comfortable with. Just avoid accident-prone people, small kids etc.

The cable is quite short at 1.2m (it’s terminated with a 3.5mm plug). And finally, these are open headphones that do nothing to isolate you from the outside world, and vice versa. Forget noise cancelling. Forget using them on trains and such like, unless you want to annoy other people. Not a problem if you know it.

Sound quality

To assess the Porta Pro’s sound I tried them every which way. Out of my laptop’s headphone socket. Through all three of Audioquest’s Dragonfly dongle DACs. From an old LGV30 phone that has that rarest of things now, a headphone socket (and top notch DAC, meaning it sounds very good). From the headphone output of a Marantz PM6006 amplifier. Through an iFi ZEN DAC VII. Even, for fun, through my Prima Luna amplifier. 

The Porta Pro sounded good through them all, even the laptop’s own headphone output sounding passable – soft overall, particularly in bass and dynamics but generally pretty listenable. Plugging a £79 Dragonfly Black into the laptop had things cooking though. The sound became much tauter, with greater detail and stronger dynamics. The Porta Pro’s midrange started to show its strengths too. At £120 it makes for an attractive combination.

Porta Pro

Moving up to the Red – sweet spot in the Dragonfly range – refined the Black’s slightly coarse treble a bit. The Cobalt brought even further gains; more clarity and a sense of delicacy and ease to the sound. The ZEN DAC VII meanwhile was a good match to the Porta Pros per se. Its bass boost setting was also useful, adding a touch of body to the sound when needed.

The latter hints at the Porta Pro’s lighter tonal character, similar to that of my Marantz PM6006 amplifier (together they make for a beautifully pristine sound). The Koss’ inexpensive drivers can’t dig deep, a rich and warm sound is off the agenda. Theirs is an open and airy vibe, capable of finesse when partnered well. 

Treble doesn’t extend overly high, as shown by comparison to dearer models like the Grado SR80X or Senneheiser 6XX headphones. And yet the Porta Pros aren’t wanting for detail, and what’s there has an unforced feel to it. Play subtle jazz from ECM – say “Hoshi Meguri no Uta” by the Shinya Fukumori Trio (For 2 Akis) – and the Koss’ reward with surprising delicacy. Their ability to conjure up the venue, to put you in the music, is excellent.

Deep bass is missing in action – no surprise. What’s there is punchy when required though. I wasn’t expecting the normal raunchy ride with “Bliss on Mushrooms” (Infected Mushroom, Head of NASA and..) but the Porta Pros rose to the challenge; the drive was awesome for their size and price. Radiohead’s “Everything In Its Right Place” was also impressive, the rolling synth surprisingly rich in tone. 

In short, the Porta Pros are uncommonly good at the frequency extremes, considering their price. They really shine in the midrange though with an easy, free-flowing sound that has you focusing on the music, not the sonics. To whit: –

“All Seems Beautiful To Me” is a single from Eric Whitacre’s forthcoming album Home. Performed by Voces8, it’s a cappella choir music par excellence. When the soprano soars it’s just heavenly. It’s well recorded too. With the Porta Pros and Dragonfly Cobalt the track had me gripped. As the music peaked at 3’30” in I was caught by surprise; genuine tears flowed. At the end of the short piece I felt drained, yet also elated. Music at its most powerful. Through £40 headphones for goodness sake.


I came to think of the Porta Pros as the audio equivalent of comfort food. Theirs is a sound I shall return to frequently, knowing I’ll be rewarded with a really satisfying listen. 

Yes, they can be bettered. All HiFi can. But that’s missing the point, these are really enjoyable headphones, regardless of their price. They work well with a range of headphone outputs, always sounding great, sometimes fabulous. Their sound is rooted in the midrange, where they excel for the price. The frequency extremes are handled well too. 

If £40 isn’t a stretch (it may be in these times) then I suggest you treat yourselves to a pair of Koss Porta Pros. If they’re your first headphones they’ll take some beating. If, like me, you seem to be building a bit of a headphone stable, they’ll be a welcome addition. Ones you’ll turn to more often than you think. Might I have just found an early contender for HiFi Starters ‘Best of 2023’? Alfie certainly seems to think so. 

porta pro