[JadeEast]

I seem to recall that the K340 simply didn't respond to damping in the way that an Ortho would. I did have some subjective success with adding felt to the front, possibly reducing some of the reflection off the giant driver exposed by modding the plastic screen. Never got rid of the coloration. Just accepted it. 

 

[bluemonkeyflyer]

Quote:

I seem to recall that the K340 simply didn't respond to damping in the way that an Ortho would. I did have some subjective success with adding felt to the front, possibly reducing some of the reflection off the giant driver exposed by modding the plastic screen. Never got rid of the coloration. Just accepted it. 

 
Thanks to all for the feedback and information. I checked the pad flap seal at the cups and they seem to be in good shape.
 
The photos in wikiphonia seem to show the electret driver is the Big one and the smaller dynamic driver is nested underneath. Is this correct? If so, the dynamic driver has a ring of (presumably) tiny vent holes all around the perimeter on the rear side. There is venting, and quite a lot of it, at the ~ 1 x 4 cm rectangular opening in the cup floors where the cable wires enter the cups. I'm not sure, but it looks like the venting may diminish with vertical rotation of the cups on the headband hanger hinges.
 
I tried modding:  with and without the stock white filament damping material x with and without Paxmate in the cups x felt vs. open cell foam over the ear side of the baffles. Results? No improvement in bass, odd SQ, and still treble Bright causing hearing fatigue after 5 to 10 minutes, even on lower volume settings. 
 
Next, I tried HiFi Man Leather pads. Results? Now there is Bass! but too much, and the treble is still shrill. There may be a way to crack this nut, after all.
 
A friend sent these to me. He has 2 more sets of these that sound good to him, unlike this set that did not sound good to him. One is modified (I don't know anything about the mod config) and I believe the other one is stock.

 

[Hutnicks]

Quote:

 
Thanks to all for the feedback and information. I checked the pad flap seal at the cups and they seem to be in good shape.
 
The photos in wikiphonia seem to show the electret driver is the Big one and the smaller dynamic driver is nested underneath. Is this correct? If so, the dynamic driver has a ring of (presumably) tiny vent holes all around the perimeter on the rear side. There is venting, and quite a lot of it, at the ~ 1 x 4 cm rectangular opening in the cup floors where the cable wires enter the cups. I'm not sure, but it looks like the venting may diminish with vertical rotation of the cups on the headband hanger hinges.
 
I tried modding:  with and without the stock white filament damping material x with and without Paxmate in the cups x felt vs. open cell foam over the ear side of the baffles. Results? No improvement in bass, odd SQ, and still treble Bright causing hearing fatigue after 5 to 10 minutes, even on lower volume settings. 
 
Next, I tried HiFi Man Leather pads. Results? Now there is Bass! but too much, and the treble is still shrill. There may be a way to crack this nut, after all.
 
A friend sent these to me. He has 2 more sets of these that sound good to him, unlike this set that did not sound good to him. One is modified (I don't know anything about the mod config) and I believe the other one is stock.

Before you do anything else try a set of velour pads.

 

[bluemonkeyflyer]

Before you do anything else try a set of velour pads.

Will do but IME velours deliver less bass. These K340's need more bass and less treble.

Thanks

 

[Hutnicks]

Quote:

Will do but IME velours deliver less bass. These K340's need more bass and less treble.

Thanks

Yes and no. The reason I love velours (other than comfort and no sweat ) is the pad itself is modable. Start with the raw pad see how they sound. Get some really soft cheap surgical tape, plastic not the paper stuff. Around the inside of the pad starting from the driver side use 3/16 or 1/4 inch strips of the tape to seal the porosity of the pad. Repeat the process again from the earside of the pads in until you find a sound you can live with. You should be able to get to a comfortable Bass level and a decently balanced treble (mostly

) this way.
 
When you get to the config you want you can make a permanent mod by smearing a thin layer of silicone sealant on the velour with your finger and pressing it in with an icecube to seal the velour permanently.
 
There's my 2 cents for the day

 

[bluemonkeyflyer]

Yes and no. The reason I love velours (other than comfort and no sweat ) is the pad itself is modable. Start with the raw pad see how they sound. Get some really soft cheap surgical tape, plastic not the paper stuff. Around the inside of the pad starting from the driver side use 3/16 or 1/4 inch strips of the tape to seal the porosity of the pad. Repeat the process again from the earside of the pads in until you find a sound you can live with. You should be able to get to a comfortable Bass level and a decently balanced treble (mostly ) this way.

When you get to the config you want you can make a permanent mod by smearing a thin layer of silicone sealant on the velour with your finger and pressing it in with an icecube to seal the velour permanently.

There's my 2 cents for the day:wink_face:

Now that is clever! Thanks so much.

 

[Armaegis]

Those AKG frames are just a pain to crack open and damp, and my experiments with the Sextett/SFI transplant were very frustrating. I'd spend more time shoving felts and other materials in front of the driver for time and sanity sake.
 
Have you ever seen what I did with my HE-6? I glued a nylon dust cover onto the earpad retention ring, put a tiny but of twaron angel hair in the middle, then a layer of soft felt on top before attaching the pad (J$ Beyers). It's essentially a little twaron pillow. The pads give me better bass resposne, and the twaron pillow chops down the treble.

 

[vid]

Quick comparison between the modded HP-50 and the HD 600 to a few tracks of this sort.
 
I went for neutrality modding the HP-50; not surprisingly, the two phones have a similar tonal balance. The 600 are somewhat brighter and sound a bit steely - it's not a veiled pair. The 50 have a bit more bass extension. Similar otherwise.
 
Not sure how big the soundstage on the 600 is normally supposed to be, but on my second-hand pair with reasonably erect pads the stage is kinda small and instruments tend to clump towards the middle. Which is fine, the 50 can't extend the stage much, either. I thought the 50 were more open to the sides and the 600 more to the middle. With this type of music, a small stage isn't an issue.
 
What sends the 50 gnawing on victory cake is smoothness and responsiveness. I thought they could give better PRaT and a more substantial-sounding rendering of the music.

 

[mypasswordis]

Quote:

Those AKG frames are just a pain to crack open and damp, and my experiments with the Sextett/SFI transplant were very frustrating. I'd spend more time shoving felts and other materials in front of the driver for time and sanity sake.
 
Have you ever seen what I did with my HE-6? I glued a nylon dust cover onto the earpad retention ring, put a tiny but of twaron angel hair in the middle, then a layer of soft felt on top before attaching the pad (J$ Beyers). It's essentially a little twaron pillow. The pads give me better bass resposne, and the twaron pillow chops down the treble.

 

K340 is much easier to open than K240 series imo. At the very least when getting an untouched K340 one should either swap out the old cotton with new cotton or replace with actual felt/damping materials. Also I found the Sextetts I owned very briefly to be very disappointing in sound, I'm guessing you think the same if you're trying to transplant SFIs in there. If anyone has recabled their K340 to dual entry or seen it done, please tell me how to do it properly, with strain reliefs and everything.

 

[vid]

The one side that worked on my LP Sextett sounded promising. I'm pretty sure AKG updated the drivers from EP/MP to LP, so depending on which version you got, try the other one, too, if you didn't fancy the sound.

 

[mypasswordis]

The one side that worked on my LP Sextett sounded promising. I'm pretty sure AKG updated the drivers from EP/MP to LP, so depending on which version you got, try the other one, too, if you didn't fancy the sound.

I had both mp and lp sextetts, neither of which I would take over a ksc75.

 

[vid]

Interesting. What was the problem?
 
I have the K 241 and K 250, both using Sextett tech. I'd take, and did take, them both over the KSC75.

 

[mypasswordis]

I dunno, I guess I couldn't get over the mid-bass hump on the MP and the overall staleness of the LP. Both had the resolving power of a rock. I've never heard a K250 but Wualta has good things to say about it other than the rolled off bass and I trust his hearing, so maybe it sounds a lot better than Sextetts.

 

[vid]

Strange - I thought the LP sounded aggressive if anything. I wouldn't think the K 250 more than a lateral upgrade, but who knows.

 

[MDR30]

Gentlemen, a fan as I am of vintage AKGs, it seems this thread has gone astray. I'm sure there are other excellent AKG threads where these matters can be discussed and also be more easy to search for those interested.
 
I haven't listened to orthos for a couple of months, been busy with my amp system and trimming my Staxes and... AKGs. Today I decided to try orthos with the system and gathered my HP50s. Turned out there were more than I remembered, even though I have picked up one now and then during the years, when they still are available. Good to have spare parts (drivers tend to fail) and be ready to mod the ultimate HP50.
 
To cut a long story short: once again the time coherence, dynamics and smooth response surprised me. Even though the sound stage cannot compete with the AKGs in size, the precision of placement in the stereo mix is astounding. This is what I call time coherence, and when this clicks the sense of air and space is just wonderful, it's so easy to identify and follow lines and instruments in the music's flow.
 
Some of the HP50s are untouched (good to have as reference), some have been modded to various degrees. What surprised me was that the first one I bought and damped actually sounded best, a battered and worn HP50S with cat scratches and all. Must have look and see what I did to that one... but basically these headphones just need a disc of felt or two.