[wualta]

 
Quote:

Man, that is a well put description of what modding orthos feels like right there! 

Ain't it though? like you're chasing something that's already being chased by something you'll have to deal with later.
 
KHB: All I'm saying is, lock one half of the project down by using/copying an existing 'phone, then make the other half and get it perfected, so you have confidence that you really understand how it works.
 
The Technics would be ideal for one way to do this: Pop the thing open, whip out the 'phragm, wave it around in your prototype magnet structure and see how it sings. If it's better than the stock magnets, you've made real progress. If the bass is distorted, you know the flux isn't uniform. That kind of thing.
 
Oop, I took too long. I like the "reverse-Wualta" idea.
 
 

 

[crimsonOkami]

I was thinking of making my own pads, it would be cheaper and an all around better fit.  I have the cups rendered in solid works, i'll post some pictures, they wont look the best because solid works has crappy graphics.
 
http://img217.imageshack.us/img217/2718/screenqqu.png
 
just googled stax sigma: those things look ridiculous lol
 
 
 
 

 

[nick n]

Quote:

I plan on using silver conductive epoxy to attach any wires onto the diaphragm, though, both because I already have some and because I really don't want to mess around with any kind of warpage. Thought about a Radioshack Cold Heat soldering pen, but I'm not worried about the epoxy degrading the signal any.

This epoxy cost much? Sounds like a great idea I have an electret that an unruly overly stiff wire fell off the contact point, was just going in to solder them now but the diaphragm is so dang close it scares me, and it's not like these things are very common for an easy replacement. Wondering if it is the same as solder for electrical signal, because these are after the transformers so any slight imbalance may become a large one. Maybe I'll get some to try on some other project anyhow.
 

 

[crimsonOkami]

"good" silver epoxy costs more than $30,  the cheap stuff doesn't have the best reputation.  Even carbon conductive glue has a better reputation than cheap silver epoxy.  don't exactly know about the distortion caused by different types of conductive glues, but i hope it isn't too much.  I think that the carbon glue probably isn't that different than the mix they use for carbon resistors, and it's only about 5 bucks.

 

[khbaur330162]

http://www.mgchemicals.com/products/8331.html
 
That's the stuff I bought. Forget where I got it and how much I paid. It's been quite a while. Resistivity looks low. Idk if I'd use it on electrets, tbh. You'd want some one with more knowledge in that area. This stuff is good for static and thermal sensitive components, obviously, but your high voltage requirement is what's making me think twice. I'd probably buy the Cold Heat pen because it's cheaper and I've seen one used before. It works as advertised. The trickiest aspect is getting the darn thing to recognize you're trying to make a connection. The nose of it has two contacts that need to be connected for the circuit to close letting it know to solder the joint. With some experience in knowing how to hold the solder just the way the pen likes it you probably won't mind, especially considering the low number of joints you'll ever need to make with it.

 

[nick n]

Quote:

"good" silver epoxy costs more than $30,  the cheap stuff doesn't have the best reputation.  Even carbon conductive glue has a better reputation than cheap silver epoxy.  don't exactly know about the distortion caused by different types of conductive glues, but i hope it isn't too much.  I think that the carbon glue probably isn't that different than the mix they use for carbon resistors, and it's only about 5 bucks.

Thanks I will drop by the big bad electronics store tomorrow and pick up some of that. It seems it's using aluminum solder so the old school roll of leaded stuff just falls off and I don't want to risk messing up the membrane If I haven't already. Plays just fine may have shortened the lifespan of it who knows.
 
Quote:

http://www.mgchemicals.com/products/8331.html
 
That's the stuff I bought. Forget where I got it and how much I paid. It's been quite a while.

Yeah good old MG Chemicals. The place I'm going will have that for sure then. Excellent!
 
 
Making changes to half of the damping scheme in the open back Pioneer SFI's. Showing promise now with a substantial change in sound. Will update as necessary for those that may have an inkling of interest. ( what exactly IS an "inkling" anyhow where did that expression come from )
 
Update: breaking news , results just in. Somebody call the mayor!

 
I will from this point not ever use felt direct damping on drivers again, and will be going back to retrofit the other pairs I have done that to if it's applicable given the cup space, don't see why not.
I do not feel it is necessary to have to put a felt layer ( disc or donut ) to damp the driver, bring up details, and/or increase highs. This has the sort of teete-rtotter/see-saw effect depending on the felt used i found: sacrifice a bit of bass using a felt disc/donut for a slight bit of treble and driver response. Well at least this isn't necessary for increasing details as I am experiencing, so the bass can fly free and still gets tightened up and the driver seems to have tightened up as well from what I can tell. ( phew longwinded and confusing  maybe I could have said that simpler )
 
How's this : if I want to keep treble and keep bass and still have a damping for the driver, and clean up the sound at the same time , from what I have gotten so far this is my tool. You may want a bit of beyond-the-driver vent damping to bring up the internal air pressure so it'll be a case by case thing and I would expect the same variable of housing size, open or closed, optimal venting to have similar effects as before.
Direct damping on both the HOK80v1 and the SFI open-back Pioneer LOOP pairs is accomplished using , yeah I know

Acousti 3 layer.Sold as "Acoustipack Extra" in single 17x18 inch sheets. But honest that horse liked being hit, and now it can be freed and live peacefully roaming vast meadows for the remainder of it's existence.
This latest thing : for the Pioneer LOOPS I removed the felt driver damping donut and cotton filler, replacing it with a disc of Acousti directly pressed to the back of the driver, behind that at the back of the cups is a disc of thin dense black felt from Rhythmdevils, and right against the outer mesh is some of that transparentish thin black fabricy stuff that's sort of like the landscape cloth you can buy but thinner. I put the denser black felt disc in there in the back to increase the air pressure that the driver has to push after it gets past the Acousti so it bumps up the bass, which from trials it actually does, while not reflecting too much back which happened when I used a double felt disc trial. It's a fine line.
The foam cannot be pressed too tightly against the back of the driver as it will cause a treble/upper mids rise. Just tight enough not to compress the outer foam layer too much and let it function as it was designed. ( had to carefully strip off the adhesive backing with an extended exacto utility knife, to do this I stuck it to the table and slowly sliced like bread as I pulled upwards) otherwise I'd be installing a jumbo reflex disc of sorts and no sound passthrough would occur. That's fine and preferrable of course if you are using a shallow cup and it's mounted directly to the rear of the cup. ( using it the normal way )
 
This stuff is giving me the exact same qualities as it has with the HOK 80.
Let's see if I can describe it without making a complete audiophool of myself, in a number of random sentences that will probably talk around the experience.( on these Pioneers )
 
* I can listen at any volume without the slightest fatigue as happened before.
* Even the slightest detail is noticeable without any traces of resonance.
* This is not because it's now "dark" or "less bright"
* Instrument placement seems improved for whatever reason, more dimensionality. This also happened with the very small enclosed HOK 80
* Instruments have realistic body or voluminous qualities now, as though it has been expanded in nature. Tones of the instruments are awesome.
* Every instrument is discernably separate without sounding artificial in any way
* Clean sound ( no booming or muddiness ), could be described as "organic" I guess.
* The music is more a feeling experience rather than a hearing experience.( that may make no sense I'm just putting that out there )
* Clangtint. Lots and lots of Clangtint. hahah a.k.a.Timbre. Funny description from wikipedia on that:"Timbre has been called a "wastebasket" attribute (Dixon Ward 1965, 55) or category (Tobias 1970, 409), or "the psychoacoustician's multidimensional waste-basket category for everything that cannot be labeled pitch or loudness"
 
This sound is so organically bodied and revealing without any resonance whatsoever to my ears.
Completely, entirely different sounding compared to before ( of a higher quality ), I do not know how to adequately convey that. If you can think of any way I can clarify anything please ask. They disappear and I get right into the music now, without thinking about future mods while I'm wearing them.
 
You're possibly going to lose some sensitivity here for driving them. Who cares.
 
Apologies for the descriptions I find it difficult to explain using the common terminologies.
Hope I didn't bore you just HAD to mention what this does. YMMV, FWIW, etc

 

[maverickronin]

The Plastidip spray seems to working so far.
 
I've put 3 light coats on the back of the Ultrasuede Ambiance and its almost air tight without anything leaking through to the front and with out making it too much stiffer.  The front is still nice and soft.  I think I'm only going to coat the inside panel since that should be all that's needed to keep the pressure in but I'll probably do a few more experiments first.

 

[khbaur330162]

Quote:

( what exactly IS an "inkling" anyhow where did that expression come from )

http://www.phrases.org.uk/meanings/have-an-inkling.html
http://www.urbandictionary.com/define.php?term=Inkling
 
Brad Bender - "A coworker used it in conversation recently. Curious about the origin. Just wondered how old does an inkling have to be before it becomes an ink?"
 
Who came up with the word thumb, or broom? Why not just sweeper? Where was I when this was decided? Some words are just weird, all are confusing if you think about it (I actually don't like English, yet what are my options?), and few are funny in and of themselves like munchkin or fpoon.
 
And good luck with repairs/tweaks. Makes me want to revisit my SFI/AT-703 disaster.
 
Edit- WHOA. Glowing review of the Acousti. I was thinking about placing an order today, but didn't bite. So wait. You removed the adhesive backing? Isn't that directly attached to the sound deadening layer? What's left? Damping material that doubles as it's own spring (and maybe the high freq absorption)? What's the difference between this stuff and Silverstone foam do you know? Have you used the Creatology Fun Foam? Now I'm really interested in this stuff for the 820's and perhaps even my HP-1 concoction...
 
Quote:

The Plastidip spray seems to working so far.
 
I've put 3 light coats on the back of the Ultrasuede Ambiance and its almost air tight without anything leaking through to the front and with out making it too much stiffer.  The front is still nice and soft.  I think I'm only going to coat the inside panel since that should be all that's needed to keep the pressure in but I'll probably do a few more experiments first.

Awesome. Glad that worked out for you.
 
Idk how you sew that three piece pattern together, but you could try spraying Plasti-Dip onto some cardboard and applying it with a fine brush to the seams or whatever before closing them up. I used a teeth whitening gel applying brush (I think... stole it from a display unit at Costco because it looked handy and I figured no one would miss it) which while being really cheap in quality was still strong enough for me to easily pry the Plasti-Dip out between coats. After three coats the brush is still going strong with all its bristles. More a testament to this method of using Plasti-Dip than the cool factor of the brush... Gives you more control over detail if you need it.
 

 

[maverickronin]

Quote:

Awesome. Glad that worked out for you.
 
Idk how you sew that three piece pattern together, but you could try spraying Plasti-Dip onto some cardboard and applying it with a fine brush to the seams or whatever before closing them up. I used a teeth whitening gel applying brush (I think... stole it from a display unit at Costco because it looked handy and I figured no one would miss it) which while being really cheap in quality was still strong enough for me to easily pry the Plasti-Dip out between coats. After three coats the brush is still going strong with all its bristles. More a testament to this method of using Plasti-Dip than the cool factor of the brush... I just figure this gives you more control over detail if you needed it.

I was just going to coat the back of the inside strip before sewing it together.  Also there are 4 pieces, the inside and outside strip and the top ring which touches your head and the bottom ring which goes against the baffle.
 
I was thinking about sealing up the seams like that too.  Even good leather pads have stitching so I don't know if it will make a difference but if I can do it without affecting comfort its worth a try.

 

[khbaur330162]

True. Come to think of it you're using memory foam... A) Where'd you get this? B) Isn't that going to seal pretty well all by itself?
 
And, randomly, on the topic of pads and that article on innerfidelity. The article talked about bass dips due to clamping force/squishiness of pads. Call me crazy, but the pad vibration often gives the bass an insane "This is intense bass" feeling which can't be measured by the dummy head. You could probably eq bass heavily sub 70-80Hz and replace with vibrators inside the pads. I wouldn't do it, but how many people off the street would even notice? I'm not saying this has an application in any way shape or form really, but interesting to think about in terms of measuring a headphone, getting back to the original article. And this is also one of the reasons I think mass loading the baffle can have a positive effect on the sound.

 

[wualta]

 
Quote:

http://www.phrases.org.uk/meanings/have-an-inkling.html
"Just wondered how old does an inkling have to be before it becomes an ink?"
 
Who came up with the word thumb, or broom? Why not just munchkin or fpoon.

Thanks Gott for this. [Patrick Stewart voice] When we're done here, we can go back to being English majors again, and all this will seem but a dubious dream. [strikes wistful pose] [curtain]

 

[khbaur330162]

Laughed out loud multiples times. Maybe a snort...
 
 
 
http://markdaniel.en.ec21.com/Planar_Ribbon_Tweeters_and_Diaphragm--1103490_1104152.html
 

 Seriously? Aw come on... I almost want to bug the guy just to see what he charges. Didn't he get the memo? Where are his headphones?
 
 
Anyway, here's the the same layout, thicker lines, moved tab for anyone interested.
http://i8.photobucket.com/albums/a5/khabur330162/AkaiASE-50_FostexT50v2CloneEdit.jpg
Dummy leads aren't needed because the spacers will be measured to sit on top of the return lines. Gimp came in handy here. Gaussian blur, altered threshold, slight touch up in one area with Paint, but overall extremely clean.

 

[vid]

Thanks for the heads-up on Tyll's latest, wualta. That's pretty interesting stuff, shame he didn't post the entire log of their conversation.
 
I need to get around to asking my phonetics prof what criteria they have for choosing headphones for speech experiments. You'd think they'd go for 'neutrality', but apparently neutral isn't quite as straightforward as a flat response curve... I know she made at least one study on how the brain responds to vowels of certain languages, where they used the Senn HD 25 for speech playback to test subjects. The HD 25 doesn't look exactly neutral in its response, so...

 

[Lurkumaural]

they used the Senn HD 25 for speech playback to test subjects. The HD 25 doesn't look exactly neutral in its response, so...

The HD25 and its "family" are considered broadcast standards these days (one of them anyway), so you'll see them on TV at sporting events and such. That could explain it.

OT, I know. Carry on.

 

[wualta]

RE phonetics experiments, it's good to keep in mind that most microphones, except instrumentation mics, are nonflat in some way as well, and can vary in their response depending on the distance to the subject, etc etc. Voice recordings can be severely band-limited and still be useful for experiments, but it would be good to see if the experimental data change when certain 'phone characteristics that have nothing directly to do with frequency response are varied... smoothness being a top candidate, to my mind.
 
KHB: Those guys showed up a year or two ago on diyaudio.com. Interesting stuff, but is it as good as the hype, and so on.