Orthodynamic Roundup - Page 31

Right. We're not advocating the defacement of any headphones but the T40 and the CV-130. The kind of cavity resonance we're dealing with is a smaller variant on the "cupped hands" sound you get when you're trying to make a megaphone out of your hands. Normally this would be considered a coloration, but of course a savvy designer can use it to acoustically EQ his design.

You may have started a rush to buy Coby CV-130s to harvest the foam rings so people can try them on their ringless baffles..


No, but a little squirt of DeoxIT and a good cleansing wiggle (ie, rotate the plug in the jack a few times to work in the DeoxIT) couldn't hoit.

Cookies will figure into an Orthodynamic story shortly. Never you fear.

I say velcro that sucker right to the Fostex cup. Then you can use a real shortie cord. Then you can have a fortie with your shortie cordie and a cookie on the side.

Right, and Fostex being Fostex, it'll be available, though maybe a mite more spendy than you'd like. Chances are pretty good DeoxIT'll fix it.

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Yeah, the driver is surprisingly less efficient than the T20v2's. Don't know why Fostex made it that way.

The T40v1 is a good 'phone, stock. It's just not the electrostatic-like thing people have come to expect after reading my neverending rants. But it bends toward electrostat sound very nicely with a mod so easy it's almost ludicrous.

Why did he make you promise not to mod your T40?

Hee hee. Did you sign the agreement in blood?

Do keep in mind that everything I've described is either easily reversible or virtually reversible. You can hot-glue the foam rings back down or let the earpads hold them in. No dremel trickery, no holes, not even sticky tape. The only other bit is the insertion of a big opencell foam spring sufficient to press the existing damping film against the driver, similar to what the factory put in the T20v2.

>shrug<

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Helpful Household Hints...

...from Helowualta:

Need something to cut out discs of felt or paper or whathaveyou that'll fit on a 55mm driver? You could trace around the driver itself, but the wires get in the way. Try this: grab an aluminum Coke can, turn it upside down and trace around the lip. It's just smaller than 55mm, precisely what you want.

Crave further homey under-the-sink approaches to modification of finely-engineered, hyperexpensive collectible heirloom headphones? See the suggestions in post 457 below. Only some of them are facetious.

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Ah, I see, a little circle-drawy thing to help out when you're drawing Inkmo the cartoon character's head.

Aw, man, now that you've told us that, all the magic and mystery of cartooning is gone!

Don't forget to go to the dollar store and get some of that fake chamois stuff.

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Scroungers for Acoustic Resistance

Not only, but also. We're about finding springy and dampy materials all over the place.

A university ought to contain piles and piles of likely stuff.

Shipping cartons (and the foam therein) in the dumpster outside the computer lab, professional-grade dryer lint in the off-campus laundromats. Foam in thin sheets, open and closed cell, foam in thick eggy chunks.. peat moss.. various acoustic resistances from just about anywhere, limited only by your enterprising imagination. Fishfoam (from the pet store), big-cell stiff foam for springs to push damping discs against drivers. Dollar-store vinyl ponchos and/or sticky dots (for reflex discs 'n' dots). Then there's the classic fabric-store felt of course, old spiderwebs, gin (optional), bits of the fiberglass backing from old suspended ceilings, the cheap dollar-store "magic eraser" pads.. there's all kinds of stuff you can try. Some of it will work in speakers too.

The fake chamois happens to be the long-sought extra-tight damping material for those who, in the words of tyre, find the "bass bleeding into the midrange" and want to do the job without one of the big reflex discs behind the damping disc. Not always necessary, but something to try before you die, just to see what extra damping does to the sound. Sometimes it is necessary.

Mind you, this is the cheap orange paper-based fake chamois, not the more expensive microfiber fake chamois. As ericj would have it, we are also Team Cheap Bastards, out to see how much fun we can have with pocket change and forgotten headphones.

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swt61's donutphones arrive

I picked them up from the post office on my way to work. I pulled them out briefly to show my colleagues and got an "oooh!" from the headphone-savvy among them.

Preliminary twizzling coming up.

I have my own HP-1 standing by for comparison. Like Steve's, the drivers have been Stage One modified (felt disc against the back of the driver, nothing more). I'm using a portable CD player with an optical out feeding a Panasonic SA-XR10 with all controls set flat. Steve had the 'phones rewired for dual-mono (aka "balanced") operation, so I'm using a supplied 1/4" TRS (tip-ring-sleeve) adapter for use with my gear. The Panasonic's rated at 100 fake watts at 6 ohms; I figure ~50 real watts at 8 ohms in stereo mode.

Also standing by: modded Fostex T20v2 and modded Yamaha YH-100.

Thanks to Steve and his collaborators for this opportunity!


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What do they sound like? Listening tests/comparisons pending. For details of construction and the progress of the mods (if any), see the Chocolate Donuts thread. Since they're not typical Ortho headphones because of the way the cup is constructed, I thought it better to give them space on their own thread.

Hint: like any good Ortho, they can be manipulated by the user to have a great variety of sound "flavors". Even changing the pads from circumaural to supra-aural makes a big difference, as we found with the Fostex. Take a look.

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What Facel-V said.
Although any acoustic resistance will be an improvement, to do it right and reach the level of sound quality where you'll say it's not that far off from a Stax Lambda Pro (but with a reduced "headstage"), you'll want to use felt as we showed earlier in this thread. I don't recall exactly how thick those face pads are when they're compressed, but it's possible there won't be enough room between the back of the driver and the back of the cup. It's pretty tight in there.

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Hm.. mine are pretty okay in the bass unassisted, though they're not piledrivers like the YH-100.

But yes, however yours turn out, they'll take bass boost beautifully as long as your amp can supply the current.