Koss Portapro headphone mod...

[keantoken]

Hi everyone.

There is no headphone forum so...

I put it here.

Some time ago I got some Koss portapros after reading several positive commercial and user reviews. I was happy, but i noticed this faint buzzing/hissing that was being caused by the crappy foam earpads as the air whooshed through them (it was not AC hum or amp noise, I know this for sure). So I read some mods online that talk about cutting holes in the pads. This helped a lot.

Having my curiosity peaked, I read more mods about putting holes in the black cover protecting the transducer, so there is a line-of-sight between the ear and transducer.

I wanted a way to cover the transducer without blocking the sound, so I did this. It looks quite nice.

It should work on several other headphone models. However, by doing this I've messed with the response and tonal balance a lot. It might be a bit bright for some. I haven't used them enough to know for sure what good it did (although the buzzing earpads was a real problem that I'm glad to have out of the way).

P.S. why does my thread title have a "thumb down" symbol by it? I did not select this.

- keantoken

[FullRangeMan]

Dear Keantoken,
Iam surprised Koss Still make this headphone!! In the late 1980 years I bought on set of this, the sound was awful, strong mids and hi, the blade coil hurts my head and ear, no transparency etc.. My Koss do not have this fishing line and the foam rotten in afew years. I have it yet stored in some drawer.
If the sound is the same quality now I should said to you give away this thing for do not prejudice your hearing(deafness) and buy a Sennheiser you will love the sound. Koss is for Pro audio people that have a hard ear, not for Hi-Fi.
Sorry for the bad news.

[keantoken]

I am glad for your input.

You must know that I read many different reviews (commercial and on forums) and the Sennheiser PX100 were most times considered on-par with my Koss.

These are not super hi-fi headphones, they only costed me about $32. I was looking for the best value for a budget headphone and this is what I ended up with; I got exactly what I was looking for.

These headphones have very strong bass, to the point of discomfort. The modifications have helped with that...

- keantoken

[adason]

I completely disagree, FullRangeMan. Koss Porta Pro are one of the best sounding small headphones, in my opinion. I have numerous headphones, since I enjoy listening late and do not want to disturb others. Have built numerous headphone amps as well. I have Sennheiser too, but they do not compare to Koss Porta Pro.
(I am not comparing big all around the ear headphones here)
The "Pro" on Koss Porta Pro has absolutely nothing to do with "Pro" as "professional". Koss Porta Pro were designed for walkman, discman and other portable applications. For small headphones have quite an amazing amount of bass. They fit snugly and stay tight without being uncomfortable. I can have them for hours without listening fatigue or pain on earlobes.
Just my opinion.
Ed

[motherone]

The Koss KSC-75 (same drivers as the portapro/sportapros, I think) is one of the best budget phones out there. I would put them up against my Grado SR-60/SR-80's any day of the week. And for $12-20, they're 1/3 to 1/4 the cost.

Anyways, Koss cans are probably the best bang-for-the-buck headphones out there, in my not-so-humble-opinion.

[keantoken]

I remember someone on another forum saying they put the portapro drivers into the KSC-75 cans with good results (maybe they meant KSC-25?). Although this doesn't make much sense if they actually were the same drivers.

Adason, can you recommend a certain headamp for the portapros?

Thanks,
- keantoken

[motherone]

My older KSC-75's appear to have the same drivers as shown above. The new ones are titanium jobs. They still sound great, but they probably aren't quite as good as the old ones.

[FullRangeMan]

Originally Posted by adason

I completely disagree, FullRangeMan. Koss Porta Pro are one of the best sounding small headphones, in my opinion. I have numerous headphones, since I enjoy listening late and do not want to disturb others. Have built numerous headphone amps as well. I have Sennheiser too, but they do not compare to Koss Porta Pro.
(I am not comparing big all around the ear headphones here)
The "Pro" on Koss Porta Pro has absolutely nothing to do with "Pro" as "professional". Koss Porta Pro were designed for walkman, discman and other portable applications. For small headphones have quite an amazing amount of bass. They fit snugly and stay tight without being uncomfortable. I can have them for hours without listening fatigue or pain on earlobes.
Just my opinion. Ed

Dear Adason,
Here in Brazil in the last years the PortaPro is widely used in stage, radio and TV studios, he put the old favorite (AKG) in second place due the high prices of goods from the euro zone.
Dear Keantoken, Sorry my stupidity for speaking of the PortaPro, mine was bought in 1987 and I never liked the sound, but now been over 20 years and the product must have improved a lot. Sorry again.
Regards.

[adason]

"Adason, can you recommend a certain headamp for the portapros?"

yes, this is my favourite:
http://headwize.com/projects/showfil...arbour_prj.htm

No need to appologize FullRangeMan, I just had different opinion, so I expressed it. The fact that this headphone has been around for such a long time is amazing. It would not last so long if it was not any good. I am sure there were improvements over time, but it was good right after release. There must have been something else wrong if you did not like the sound. Many "phones" jacks suck.

Ed

[qingcai]

head-fi.org is a headphone forum, lots of guy crowed over there.