HD800 "French Mod" aka "SuperDupont Resonator"

I have a whole pack of Large Shure Olives back from when I had the SE535... They're pretty much sitting around doing nothing right now, this is going to be hard to resist.

 

But those tips are a closed cell foam aren't they? So pretty much all we're doing is reducing the size of the butt hole?

 

My 2¢
A couple of points, just in passing…

#1 you can very easily disconnect the ear cup assembly from the head band by unscrewing those 2 #8 torx screws.
Once done the ability to deal with the ear cup assembly and the driver itself is much more direct and way less cumbersome.

#2 These mods suggest (at least to me) changing the id of the central hole (the difference between the ID and OD of the inserted 'plug').

#3 The shape of the ends of the 'plug' that faces the driver and our ears might also make a significant difference.
I would think a non flat surface (ie. tapered or rounded) would perform better.

Perhaps not, but these would be easy (and cheap) experiments to make to see how modifying the shape of the 'plug' can be of help.

In my minds eye I can also see where tapering the central hole on either or both sides (inside and outside) could also help in refining the changes these 'plugs' can make.

Performing these experiments might also shed some light on the influence of the 'density' (overall thickness) that these 'plugs' have upon the FR.

JJ

 

"Just the tip"

Seeing how easy it is to make the HD-800 'listenable' I might pick a pair up someday and see if they're for me.

 

opcorn:, need to grab myself some shure olives tonight. Reading the Helmhotz resonator theory the most important factors are the hole diameter and volume/length of the 'neck' or tip and the external enclosed volume right behind the driver

 

sortof surprised why an owner of an HD800S hasn't removed the damper from their S just to take a closer look and dimension measurements.

 

At the cost of possibly breaking it? I think he would know better if he really wants to do it.

 

Amazing work sorrodje! Can't wait to see your further measurements and how this and oj's companion thread develop.

 

Axel Grell filing lawsuit in 3... 2...

But srsly, reading about this mod made my day. Judging from the look of the graphs, I'm not sure I would be able to tell the difference between a French-modded HD800 and HD800S in a blind test. This should be a monumental milestone in the history of HD800 mod.

 

@sorrodje I'm doing exactly that ordered the 910Ls and T400s for testing.

I'll also try to pull the middle thing out from the 910Ls and make the hole a bit bigger for science. Will report back tonight with my own mods + the new resonator. Might try (which is gonna be damn arduous task since it's a giant thing of 3cm thick) to cut some open cell foam, who knows it could be superior to the foam tips. But don't quote me on the last part definitely gonna try the T400s (arriving tomorrow) and the 910Ls tonight.

 

Where is the pic of the factory resonator?

 

Thanks for that. While I appreciate the measurements, I'd be most interested in what you're actually hearing.

Also, if the screen that is removed is glued how are you getting it to stay on when replacing it? Sorry if I missed this.

 

@sorrodje Can you take a picture of the resonator of the HD800S with a ruler so that people can get an idea of scale?

 

For the moment the only significant feedback I can give to all hd800 owners out there is this :



Unfortunately I'm not in a position to give a detailed feedback, as my current amp isn't much suited for the hd800.
But, everyone should do this. It's so simple, it'd be a shame not to at least try it.

 

@frenchbat Je suis dessus, Superdupont!

Haha my French has declined to extremely poor over the years. But yeah in a few hours I will try my first attempt with the Shure tips and redo them with the T400s.