[vid]

I wouldn't want to bother Tyll too much with my green questions, at least not yet. I'm learning lots from him as it is, though; his Building a Headphone Measurement Lab was interesting, as are his graphs and analyses.
 
(And while looking at his graphs – raw vs. compensated – I've become pretty sure that the way I apply the HRTF is wrong. Apparently it isn't EQ'd in, but simply subtracted 1:1. When I EQ in the HRTF, the bottom end gets lifted up, but you don't see that happening in any of Tyll's graphs. In fact what I seem to see in them is that energy simply vanishes as he applies the HRTF, i.e. it would be a straightforward x - y dB thing. Or so it seems.)
 
I don't know much about microphones, so I was a bit naive there about the MD 421. Thanks for looking it up.
 
(I'll admit to enjoying the feeling of cleaning up old headphones and having them look fresh and new despite their not really being so.)

 

[rhythmdevils]

Does anyone have extra Fostex damping foams or the stock white diaper/paper from a T20v2 (from the back of the driver)?  I'm happy to pay for them, it would save me having to track down a pair just for the damping.  And I bet some of ya'll don't use them or have removed them. 
 
I can also trade...

 

[rhythmdevils]

Also, potential good deal on some nice earpads... http://www.head-fi.org/t/594575/dt880-250-ohm-05-w-jmoney-pads

 

[KANA]

Quote:

Does anyone have extra Fostex damping foams or the stock white diaper/paper from a T20v2 (from the back of the driver)?  I'm happy to pay for them, it would save me having to track down a pair just for the damping.  And I bet some of ya'll don't use them or have removed them. 
 
I can also trade...

 
I have T20 (don't know the version), but I love this sound (even more than T50).
So I don't wanna separate the parts, sorry.

 

[wualta]

RD: I wonder if there are some porous grades of Tyvek or similar nonwovens that are hiding under our noses in hardware stores and the like. "Diaper" material in bulk, in other words, like maybe some grades of lab filter paper.
 
Or maybe the filters used in my AeroPress: http://aerobie.com/images/filters.jpg  Not the same as drip grind filters, since the 'Press brews under pressure, so the holes are smaller. I don't know how this filter paper compares in porosity to the Fostex "diapers", but at least it's available and cheap. 62mm diameter.
 
Turns out there's a $15 permanent filter for the 'Press that might be useful for folks doing experiments: http://www.marco.org/media/2012/01/aeropress-stainless-steel-disk.jpg

 

[ludoo]

Anybody interested in laser-cut baffles to properly fit SFI drivers to the cheap and readily available Sony MDR-ZX100?
 

 
I found a pair of 32ohm SFIs in a drawer, and thought of doing a proper job this time as these are my last pair and there aren't many to be found nowadays. So I bought the ZX100 since they are cheap, and every store carries them so the final product can be easily replicated if it's any good (Yamaha's rh5-ma would have been better as they are better built, better looking and more comfortable, but they cost too much).
 
The only problem with the ZX100 is their driver is too small (30mm vs almost 39 for the SFI driver), so quite a bit of surgery is required on the baffle to make a fit, and the result will be messy. The Sony baffles are also full of holes and don't seal properly with the cups, so I though about making replacement baffles.
 
What I'll be doing is draw simple baffles to be laser cut on plexiglass.My initial idea is to have them composed of two parts: a 2mm thick disc for the baffle proper with a center hole the right size for the SFI driver and two small holes for the screws, and a thinner disc of a smaller diameter and thickness to be glued on top of that, with a smaller center hole which leaves 1mm all around to act as a stopper for the driver. The idea is to have the driver as near as the ear as possible, and to eliminate all holes and spaces between baffle and cup (the pads will need to be glued on the baffle like on the HP1 etc.).
 
I will send the drawings to the cutter this weekend to be cut, and since each sheet holds 4 or 6 pieces and I only need 2, if anybody is interested I might sell the remaining ones at cost (a few euros, plus postage). I can also make more if needed or share the (very simple) drawings. If everything works well, I'll also have some replica Fostex T20 badges made as mines are missing them, and maybe experiment with wooden cups made of laser-cut discs glued together, and/or rear cup designs with engravings and tuned bass ports.
 
Oh, and the search engine is indexing again, I fixed it yesterday.

 

[wualta]

A hearty Yaaaay! to all of the above, the idea, the offer and the search engine. Exclamation marks all around.
 
Oh-- I just saw Tyll Hertsens' latest blog entry wherein he and a bunch of hard-headed orthonauts are really bearing down on the Neo Ortho driver-variability problem and the related measurement-repeatability problem. Good reading.

 

[ludoo]

Quote:

A hearty Yaaaay! to all of the above, the idea, the offer and the search engine. Exclamation marks all around.
 
Oh-- I just saw Tyll Hertsens' latest blog entry wherein he and a bunch of hard-headed orthonauts are really bearing down on the Neo Ortho driver-variability problem and the related measurement-repeatability problem. Good reading.

Hah, I hope it's a project I'll be able to finish soon, and not end up in one of the many closets full of junk (lenses, cameras, headphones, amps) I have.
 
As for Tyll's blog, interesting article though spending 2k for headphones is something I'll never do.
 

 

[rhythmdevils]

Quote:

 
I have T20 (don't know the version), but I love this sound (even more than T50).
So I don't wanna separate the parts, sorry.

I wouldn't even dream of it!  I just thought I'd ask.  It'll be fun to track down a v2 again.   
 
Quote:

RD: I wonder if there are some porous grades of Tyvek or similar nonwovens that are hiding under our noses in hardware stores and the like. "Diaper" material in bulk, in other words, like maybe some grades of lab filter paper.
 
Or maybe the filters used in my AeroPress: http://aerobie.com/images/filters.jpg  Not the same as drip grind filters, since the 'Press brews under pressure, so the holes are smaller. I don't know how this filter paper compares in porosity to the Fostex "diapers", but at least it's available and cheap. 62mm diameter.
 
Turns out there's a $15 permanent filter for the 'Press that might be useful for folks doing experiments: http://www.marco.org/media/2012/01/aeropress-stainless-steel-disk.jpg

I think there's huge potential in the porous paper-y substance on the back of the driver.  Seems to be exactly what the driver wants, except I have very few kinds here to play with.  I tried going to an art store and looking through their handmade papers, but didn't get too far with that approach. 
 
I think some kind of industrial filter sample pack would be ideal.  My father runs a lab at Stanford and knew of something like this but that hasn't panned out yet....

 

[ludoo]

Laser-cut baffles for the Sony are 1.50€ each including materials, from the ponoko Italian site, if I go pick them up (not too far from here, about 40min). I wonder why nobody has discovered this before. Engraving is very expensive but simple cutting is really cheap.

 

[wualta]

Hmm, I wonder how good lasers are at punching thousands of tiny holes of a predictable size in metal foil...?

 

[JadeEast]

Coffee filters are pretty dense. The aeropress disk and the Hario v-60 paper cone in my kitchen are both very resistant to attempts to blow through them. Oddly enough, (maybe not that odd considering the audience of this thread) I have used synthetic felt as a filter for the Aeropress when I ran out of paper filters. 
 
 
 
 

 

[nick n]

There is a peculiar fabric that can be found on cheap dollar store collapsible shoe holders and crummy little zip-up bags with the clear plastic fronts that may be worth looking into. You get a bunch of it for next to nothing. Have a peek around your local dollar store you'll see what I mean. It's a porous semi-transparent white fabric that looks almost dimpled.

 

[wualta]

 
Quote:

Coffee filters are pretty dense. The aeropress disk and the Hario v-60 paper cone in my kitchen are both very resistant to attempts to blow through them. Oddly enough, (maybe not that odd considering the audience of this thread) I have used synthetic felt as a filter for the Aeropress when I ran out of paper filters. 

An Aeropressagent is brave and thrifty and knows what to do when the filters run out. I'm trying to remember my results were when I tried drip-type coffee filters as damping layers. I thought I'd concluded they weren't dense enough, but I could be wrong.
 
I don't know what a Hario V-60 is, but it should be a headphone. Or a BMX bike.

Quote:

There is a peculiar fabric that can be found on cheap dollar store collapsible shoe holders and crummy little zip-up bags with the clear plastic fronts that may be worth looking into. You get a bunch of it for next to nothing. Have a peek around your local dollar store you'll see what I mean. It's a porous semi-transparent white fabric that looks almost dimpled.

Trying to picture it.. is it about the same weave and thickness as dryer sheets?
 
 

 

[nick n]

I'll go try to picture it literally, and at the same time I think it's quad shot espresso time + hot water = americano. Guess I'm up all night thanks to you fellers.


Shot with the book had no flash so it would decently show the transparency. I have yet to use this in a project. May not be what you are after. Seems strong. See I can't even hold the book still due to caffeine intake. Definitely thicker than drier sheets but how much I can't say.
 
I'll try it on my next SFI project.