Koss Porta Pro

Actually I think it’s plastic. I haven’t looked real closely for a while. Anyway, I’m talking about the disc that covers the driver that has holes and slots in it. I’m pretty sure the factory foam pads cover everything, but what I have on my 35s now expose that middle section.

On my original pair of 75s I removed the disc and drilled more holes in it per some mod I read on headfi or someplace. This was a few years ago. I can’t say that it necessarily improved anything except that the theory was that it would make it more open an detailed sounding. On $15 headphones I have no problem trying crazy stuff to see if it works.

A couple years ago I took a pair of closed back Sennheisers HD-201 that my kids had blown and put Koss 75 drivers in them after modifying the mounting baffle of the Sennheisers. They sounded like ass. But it was a cheap experiment in hopes I could have a cheap pair of closed backs for work.

 

Ah, yes, they are the usual plastic baffles. For a minute I thought you came across an unkown version of the driver.

 

Thanks -- I wasn't aware of that version. It looks a little beefier around the plug (beefier strain relief), but otherwise pretty similar to Porta-Pro models that have the smartphone remote on the cable. The 25th anniversary model had upgraded OFC cables with a two-tone cloth jacket. I'd imagine any difference in sound is minor, but I still kind of regret not buying a pair at the time.

 

Thanks for the measurements -- that's interesting to see.

I just checked and you're right, the KSC-35 are gone from the Koss website. They were still there when I checked in early October. Guess they're gone for good.

 

https://theheadphonelist.com/yaxi-ear-pads-for-koss-porta-pro-review/

So according to this site, these replacement pads "effectively reduce veil, are more detailed, enhance comfort, and are cost effective" ($12 plus shipping). Don't have too much experience with this site, but they at least seem to be semi-legit, in the sense they're not handing out 10/10's left and right and seem somewhat objective. Apparently international availability may vary, but couldn't find anything on them anywhere else.

 

A mechanical engineer and I designed the Porta Pro before leaving Koss in 1984 (they went into Chapter 11). I've been an acoustic engineer in audio for nearly 50 years now. Good to see Koss kept these around and that there's still an audience for them.

 

@misterears provenance might be appreciated because that's a bit of a bold claim, but at the same time I dunno why anyone would misrepresent themselves that way, haha.

(The internet has turned me into a skeptic)

Had I no need for isolation I'd likely have a PortaPro or two lying around. My old manager had a pair that I got to try on a few occasions and it was an absolute treat listening to them— you and that engineer did an excellent job!

 

Still one of the best sq/$ ratios in audio.

 

One of the greatest headphone of all time. After a few years in Sennheiser land, I'm back to the faster, cheaper Porta Pro! I have no need for other open cans.

 

Edit: this post was inspired by @Psalmanazar excellent post above.

Show me better for the $$$

 

How's the massdrop version versus the original? I'm listening to the black amazon version as I write this.

 

Mostly cosmetic. The Drop version is all blacked out/midnight. And the cable seems a bit more sturdy and not the standard zip cord.

 

I actually never tried original PortaPro; I only have regular KSC75’s.

 

Depends if you're a 650 or a 600 fan. KSC75 (on a cheap headband) has that bit of a 3k bump...

 

Put a parts express headband on them and you’re pretty much there. Except PortaPros will have more head clamping force. Personally I’d rather have KSC75s or ‘35s with the cheap headband.

 

I prefer the KSC75 over the PortaPros. I like its "metallic" brightness over the darker Portas and has a wonderful natural openness that gives it a wide headstage. Not as warm as the PortaPros, but I think the bass is slightly more refined on the KSC75, it doesn't have the same muddy impact that can bleed in the mids. I especially love listening to old mono Motown records or even "poorly" recorded/mastered albums like DJ Shadow's "Endtroducing" on the Koss' over a Hi-Fi setup because it can smooth over the harshness.

An alternative to the Parts Express headband would be to buy a Koss SportaPro, remove the drivers and snap them into the KSC75 ear clips. There's more of a gap between your ears and the cushions compared to the KSC35, but the KSC35 uses the identical drivers as the PortaPros except without those plastic clips which can be a little sharp on the ears after an extended amount of time. I could wear the KSC75 clips for 8 hours without any ear discomfort.

I also prefer the treble from whatever crappy Sabre DAC is in my LGV30 over the Fulla 2. I'm weird.

I just wish Koss would go back making the original KTXPRO1 when they were the OEM for RadioShack. I bought a newer pair a year ago and they ruined it. Pads are way too thin, super closed-in stage, distorted transients and the plastic construction worse than a free airline headphone. I bought a few KSC75s as backups just in case Koss fucks with them.

They are my mobile choice over IEMs. I worry I'll damage my hearing with IEMs cause I listen to loud music.

+1 PortaPro/Fulla 2 club:

Swapped out the stock pads for the Yaxi pads (Better comfort and still maintains the PortaPro sound): https://www.yaxi.jp/onlineshop/

 

For a sturdier but still cheap alternative to the Parts Express headband for KSC75 drivers: cannibalize a pair of KPH7s as described here.

 

I like my Massdrop KSC75s + LG V20 better than anything else. Except maybe my old not Massdrop KSC75s. Or perhaps my Massdrop PortaPros.

I think the bass is a bit more convincing with the Porta Pro and am not sure it bleeds into the mids more than the KSCs, it's more that the highs on the PPs are a bit restrained so the overall sound feels a little thick sometimes.

I keep meaning to buy Massdrop Sennheiser HD 6xx (marketing works!) but then I listen with my KSC75s headband and feel very, very reluctant to to spend the equivalent of 300 bottles of my favourite "guzzling mass quantities" beer (Banks's Bitter) when I already feel content. Also I can afford to lose/break the KSCs and buy another, or get brave with a soldering iron and recable if/when necessary.

Btw I'm not sure there is anything much wrong at all with the audio in LG's V series. Some people make a thing of "sabre glare" but this has been shown to be an implementation error in some devices, not a deficiency in the hardware.

 

Those Yaxi pads look about the same size as the Sennheiser HD414 pads which are available on Amazon. Much more comfort, less bass (for better imo) and larger soundstage. After adding HD414 pads I sold my other efficient open headphone the HD58X.