[Cheeseboy]

I left JVC a couple of years ago.  While I was there, I got tons of freebie headphones from the accessories manager.  One of my favorites was the HA-S650.  I never heard the HA-S400.  But, if they are similar, the HA-S400 must be a great bargain.   I still use the cheapie Gumy headphones when I am in my cubicle.  Those are bargains too.

I was there quite a few years before you.  My job was to develop VHS in the US for JVC. 1979 to 1994.  I'm feelin old.  When it came to turntables, cassette decks and headphones JVC hit the long ball quite often.   The Gumys and Jellies are good throw aways.  Have you tried the washing machine mod on them?  It never seems to work for me.  Somehow I keep doing it. 

There was no accessories manager so we all sold everything.  Can you say Japan sample!!!!!

Steve

[Rclark]

ordered. Although Headphones will still be a tiny portion of my time and that's why these are perfect. Now I need a preamp/amp. a giant killer to match the $27 headphones.

[charmerci]

OK done. Much, much better.

Take off the pads.







Undo the three screws.





I put duct tape on this surface. Ideally, it would be a thin, sticky foam because we are trying to stop this surface from vibrating from the backwave of the speaker.





Added a piece of cotton (old sock not TP) to reduce reflections. Ideally, you could add the duct tape to surrounding surface of the backside of where the speaker is placed. It's small and I didn't want to make the effort.





Taped most of the front surface. Again, because this is where the speaker is attached, you want to reduce the extraneous vibrations as much as possible. If you tap on the plastic parts before and after you do this, you can easily hear the deadening of sound.





And viola! You have an infinitely better set of headphones than when you first get them. I first complained about recessed mids and highs. Gone. They are now inside your head. Much more balanced overall. Almost all of the boominess is gone! The mid-upper bass is still predominately heavy - remember I'm just talking about unequalized listening - unless we're talking MP3 playback.

These are nice headphones! (But only after dampening all that cheap plastic resonating!) 

Thanks for all the recommendations and links!

[SET Man]

Hey!

   Well, thanks to you guys with this thread I got one on my way too! Yeah, I just spent $27 of my heard earned cash because of you guys. 
   

OK done. Much, much better.
....

   I did similar mod to my AKG K77 that I bought around mid last year. Too bad I didn't know about this JVC, otherwise I might have skip and save money and get the JVC instead.

    Here is what I did....





  Using thick 3M Scotch 2242 Rubber Electrical Tape to damp the plastic cups.



  Cork mat glued on using 3M 77 adhesive spray. And using a gram of Acousta-Stuff to stuff the inside the cups. The result is very good, no more plasticky and hollow sounding. Better definition and fuller bass.

    I'm planning to do the same with the JVC when I received them after some break-in. I think the JVC will be better for me since taking the AKG K77 outside is a bit cumbersome and they make noise when I walk... not good 

Take care,
Buddy

[funkmonkey]

I put duct tape on this surface. Ideally, it would be a thin, sticky foam because we are trying to stop this surface from vibrating from the backwave of the speaker...
...These are nice headphones! (But only after dampening all that cheap plastic resonating!) 

Thanks for all the recommendations and links!

I wonder if some black foam tape would fit the bill...  I use a few varieties at work (mostly 3M brand) and comes in 1/16" , 1/8"...  mostly double side sticky...  hmmmm.    or maybe the foam from an old set of earmuffs...  food for thought.

[randytsuch]

So I remember more Fostex mod info as you guys post.

For the Foster, Dynamat was used to kill the vibrations on the plastic piece that holds the speaker.

In the cup, paxmate was used to for the the back wave.

There were more mods, but I stopped tracking them.

Randy

[charmerci]

I wonder if some black foam tape would fit the bill...  I use a few varieties at work (mostly 3M brand) and comes in 1/16" , 1/8"...  mostly double side sticky...  hmmmm.    or maybe the foam from an old set of earmuffs...  food for thought.

Whatever is non-resonant is best. The only thing to worry about would be the thickness of the foam/tape stopping the plastic holder screwing back on firmly.

[wisnon]

Mine just came by mail from the UK and I also have the S600 (bought locally at FNAC) and I prefer the 400 out of the box. Better balance overall.

Lets see how they fare when broken in.

I dont find the s500s in Europe so far.

[eclein]

Awesome.....I love it, this for me is where the fun really is, take an inexpensive set and improve them immensely. Charmerci so is it night and day difference?? The mods are a huge improvement or no??
 Thanks guys for opening them up, its easy isn't it-Pads off, 3 screws and your in right?
 

[Cheeseboy]

I don't have any Dynamat so which works better for dampening headphone shells.  Electrical Tape or Duct tape? 

[randytsuch]

I don't have any Dynamat so which works better for dampening headphone shells.  Electrical Tape or Duct tape? 

My guess would be duct tape.
I would be easy enough to test, apply some tape, and them tap the shell, and see how "dead" the shell is after using the tape.  You could do one shell with electrical, and the other with duct and then compare.

Randy

[neobop]

I don't have any Dynamat so which works better for dampening headphone shells.  Electrical Tape or Duct tape?

Modelling clay works great for damping the back of the baffle and inside the cup.  You don't have to cover the entire surface of the shell. The clay will act as a sink for vibrations.  Too many layers of stuff inside the shell and you'll reduce the volume of the enclosure. If these are completely sealed, you might want to fill with dacron stuffing or cotton, pulled loose. The clay can hold the stuffing in place. Generally, sealed speakers are completely stuffed, and bass reflex has just the walls lined.
neo

[ajzepp]

If you guys want a really cool track for your JVCs to show off that nice crisp mid-bass, check out a decent quality version of "The Wilhelm Scream" off James Blake's self-titled album. It's way cool!

I can't wait to hear this track on my other headphones, too 

[murphy11]

Dumb earlier post deleted. Didn't realize I was already in the headphone forum = doohhhhh

[wisnon]

You mean like this?
http://www.stereo.net.au/forums/index.php?/topic/49078-2ch-system-for-2000-in-small-apartment/

ot this
http://www.audiocircle.com/index.php?topic=111225.0

[charmerci]

Awesome.....I love it, this for me is where the fun really is, take an inexpensive set and improve them immensely. Charmerci so is it night and day difference?? The mods are a huge improvement or no??

Night and day. Almost completely unlistenable (non-equalized) to very good (compared to more expensive ones.) The boomy resonance of the plastic is just awful.

[Nick77]

Ive been breaking these in for several hours now and they are really starting to shine. Can say the same things as noticed by others, mids were recessed and bass boomy. I did the Q-tip mod and seemed to solve the recessed mids, now i just have the boomy bass and can hear the resonance.

Going to break these in a bit more and consider adding some Dynamat for resonance and taping the ports. Even in their current listening state if someone told me they were $27 I wouldn't believe them. Thanks for the heads up Ed!

[charmerci]

Btw, it takes about 30 minutes to do my mod.

[eclein]

Ive been breaking these in for several hours now and they are really starting to shine. Can say the same things as noticed by others, mids were recessed and bass boomy. I did the Q-tip mod and seemed to solve the recessed mids, now i just have the boomy bass and can hear the resonance.

Going to break these in a bit more and consider adding some Dynamat for resonance and taping the ports. Even in their current listening state if someone told me they were $27 I wouldn't believe them. Thanks for the heads up Ed!

Don't thank me thank ajzepp who posted about them earlier, he's the man!

[ajzepp]

Don't thank me thank ajzepp who posted about them earlier, he's the man!

I'm just the messenger from what I heard on head-fi...