[JoeDoe]

You guy should try the HiFlight Mods!

 

[JoeDoe]

Deleted

 

[KimChee]

I cant remember who it was, but someone got those mods done..

 

[JoeDoe]

I cant remember who it was, but someone got those mods done..

I highly recommend them!

 

[nihontoman]

Sounds like a resonance issue caused by a loose driver unit.

 

[waynes world]

One of my ksc75 drivers also vibrated/resonated with bass at times. I figured that it was just something I'd have to live with (and not complain about since they otherwise sound so friggin good and are so ridiculously cheap). But my buddy worked some magic on them, and the resonance seems to be gone. I'm listening to some bass heavy music at fairly loud volumes, and nothing but a smile on my face. I'll report back with what he did...

 

[cmarti]

  Well, portapro classic is on the road since 1984 so it's less than one per year
 
 
 
 
There's the video. Pay attention from 0:08
 
 

I had that problem and the issue was the speaker cover which was loose.

 

[michele009]

One of my ksc75 drivers also vibrated/resonated with bass at times. I figured that it was just something I'd have to live with (and not complain about since they otherwise sound so friggin good and are so ridiculously cheap). But my buddy worked some magic on them, and the resonance seems to be gone. I'm listening to some bass heavy music at fairly loud volumes, and nothing but a smile on my face. I'll report back with what he did...

Please, let us know thank you!

I had that problem and the issue was the speaker cover which was loose.

Do you mean the black plastic cover under the foam pad? I checked already and it's ok.

 

[cmarti]

Please, let us know

thank you!
Do you mean the black plastic cover under the foam pad? I checked already and it's ok.

Yes that is what I mean, it could be a little loose.

 

[Drums4money]

Here's a lazy Sunday project that was done before I could manage to get a beer open:
 
* KSC75's on sale for $9.99
* Parts Express band (Part # 240-015) $1.99
* Senn HD414 pads leftover from a project.  $8-$10
 
The PE band comes with extra foams that are slightly thinner than the Koss ones.  Swap out the foam before slipping the yellow pads over everything. 
Driver, black foam, yellow foam, then click onto the PE band.  A few short pieces of heat shrink to set the maximum extension.  To my ears the extra foam mitigates the KSC's occasional hyper-treble.
 
Sooo lightweight.  My hair weighs more and it's getting thin & grey!
 
 
 

 

[michele009]

how are the hd414 pads compared to the stock kcs75? they seem to be thicker

 

[Drums4money]

  how are the hd414 pads compared to the stock kcs75? they seem to be thicker

 
Just a little thicker than the KSC's.  I find them VERY comfortable on this light-weight setup with so little pressure on the ears. 
 
In contrast, I prefer the Grado G-Cush on other frames. 
It felt to me like frames with a little more spring tension could eventually compress the yellow pads until the driver frame underneath was solid against the ear.
I'm not sure if the Grado pads are thicker - OR - maybe just more resistant to compression.   

 

[DozerCSX]

OK, so I've got a win-win on the "Franken-Koss" discussion here - I've been reading these threads on the KSC-75, (purchased about two weeks ago - wow!) and also a longtime owner of the Koss PortaPro... so for the record,  the Portapro, Sportapro, and KSC-35 all share the same driver - a bit warmer, with squishy bass if it gets too close to your ears.  Similarly, the KSC-75s, with their Titanium coated drivers, are a bit  edgy, and a touch thin on bass using the wonderful stock clamps.  I also recently watched a video on Youtube from an unknown guy experimenting with the same discussion (https://www.youtube.com/watch?v=Z1q9t6PAl2E) and I came up some interesting variations for y'all...
 
So, the stock Portapros headband simply pushes the drivers too close to your ears, resulting in squishy, bloated bass, extremely warm tone, and a general lack of high end.  All are easily corrected if you either (a) pull the drivers about an 8th of an inch away from your ears, or (b) run down to Radio Shack,  drop $5 on their replacement pads, and place them OVER the existing Koss Portapro pads, resulting in the same 8th of an inch lift off your ears - this is TRANSFORMATIVE, moving up the Portapros a full weight class - it tames the base, substantially increases the high end presents, and "smooths out the sound" overall for a much more pleasing and accurate sound - try it!
 
Similarly, the thin bass and harshness of the KSC75s can be simply tamed by (a) pressing the drivers ever so slightly closer on your ears than the stock earclips place them - similar net benefit on them, resulting in increased, accurate bass, and a reduction in the KSC75 high end edginess, resulting in a more pleasing, well rounded, listenable sound.
 
NOW, what if, I thought, what if I swapped my Portapro drivers and the KSC75 drivers with their respective headsets?  The Portapro drivers combined with the KSC75 ear clips would get a bit more distance, while the KSC75 drivers would get a bit closer from the Portapro headset pressure, both resulting in improved sound?  Sooo, that's what I did, and it worked beautifully to my ear - total win-win!  Someone please replicate this and give me independent confirmation on this (BTW the pressure was so great from the Portapro headset/KSC75 drivers that I wound up still using the Radio Shack pad overlays, for a tad more comfort, still retaining the sonic improvements (perhaps only a 16th of an inch net distance?)
 
Both sets now appear even better/cooler in their new homes - a PortaPro headset with silver drivers (KSC75) AND a set of KSC75 earclips combined with the Neon blue PortaPro drivers - super cool looking!  Much cooler (and cheaper) than the same mod using KSC35 black drivers.
 
Both are better in my estimation than stock - I think I slightly prefer the KSC75 clip/ Portapro driver combination as it's a touch warmer, with still a skosh more clean bass than the Portapro headset/KSC75 drivers, but either is an improved, extended listening session for me.  And both get pushed up a weight class from the improvements - that's saying alot based on the starting goodness.
 
Last thing - my listening rig is a Motorola Droid X2 running as a dedicated FLAC player using the Meridian player SW, plus a JDS Labs CmoyBB 2.1 headphone amp specifically tuned for the Portapros. 
 
Feedback, please!

 

[c61746961]

I've found similar results by just switching the earpad foams around (since the PortaPro comes with a thinner foam than the KSC75).

 

[waynes world]

All good stuff gents! I love my ksc75's on parts express headband. But I end up listening more to the sportapros with these great mods by @trindysmom:
 
http://www.head-fi.org/t/124243/kramer-mod-ksc75/435#post_9302214
http://www.youtube.com/watch?v=XMFGuNa2WEM
 
I did have the sportapro drivers on the parts express headband, but the headband is on it's last legs now, so back onto the modified sportapro headband they go. I also stretched out the headband a bit so that clamping force is reduced. Quite comfortable, and it's amazing how amazing they sound!