[ericj]

Quote:

Originally Posted by swt61 /img/forum/go_quote.gif Yeah I used methyl-ethyl ketone from a rubber supplier. I knew that glue wouldn't hold. I thought about wrapping it with a thin strip of fiberglass and resin, but I never got around to trying that.

Well poop. That was the best idea I've had.

I can see what wualta is getting at with the screw idea, but I've tried that sort of thing with other broken plastic tubes. The trouble with that is you never get the pieces to mate perfectly when you're threading a screw between them unless they are in one piece or clamped together when you start - and the torque involved with driving the screw in will break the sort of bond that needs reinforcing.

Perhaps MEK is the wrong solvent for this stuff? I know a guy who used to do some sort of engineering at an injection molding factory, one of these days I'll pick his brain a bit.

 

[swt61]

Quote:

Originally Posted by ericj /img/forum/go_quote.gif Well poop. That was the best idea I've had. I can see what wualta is getting at with the screw idea, but I've tried that sort of thing with other broken plastic tubes. The trouble with that is you never get the pieces to mate perfectly when you're threading a screw between them unless they are in one piece or clamped together when you start - and the torque involved with driving the screw in will break the sort of bond that needs reinforcing. Perhaps MEK is the wrong solvent for this stuff? I know a guy who used to do some sort of engineering at an injection molding factory, one of these days I'll pick his brain a bit.

When I was in my early twenties I had a Honda Elite scooter. The engine block developed a stress crack, and my Dad (an aircraft mechanic) brought some special epoxy home and puddled it over the crack. That stuff worked fantastic and was the best holding stuff I ever saw. Sadly my Dad has passed away, and I have no idea what the epoxy was. I bet it would work fantastic though.

 

[wualta]

JB Weld?

I do like the idea of wrapping the tube in some sort of glass fiber reinforcement and then applying a layer of epoxy or urethane glue.

 

[philodox]

Quote:

Originally Posted by setmenu /img/forum/go_quote.gif You know, these things are not that difficult the make. With all the enthusiasm and knowledge here, we could design and build our own ideal planar phones! Much more fun than tinkering with old ones I can assure you!

Now that sounds like a cool idea.

I'm in.

 

[facelvega]

Quote:

Originally Posted by setmenu /img/forum/go_quote.gif You know, these things are not that difficult the make. With all the enthusiasm and knowledge here, we could design and build our own ideal planar phones! Much more fun than tinkering with old ones I can assure you! wualta What do ya think! Could be a fun excercise... .

We could try getting in touch with Willi Pressuti with the proposition of starting with the old MB ortho drivers and working forward from there. Maybe they'd even do a limited run of them. Probably easier than getting Yamaha or Foster's to cough up rights to their old patents.

 

[wualta]

Quote:

Originally Posted by facelvega We could try getting in touch with Willi Presutti with the proposition of starting with the old MB ortho drivers and working forward from there. Maybe they'd even do a limited run of them.

Sounds interesting, but we'd have to make it attractive to his company from a business angle. That would mean a pretty big run. Are you still in touch with Willi? The MB Quart website gives his email as willip@maxxsonics.com.

What I secretly hope-- I shouldn't even be telling you this out loud-- is to get some company interested in starting from the Fostex T50 design, use neodymium magnets with a more open magnet structure, come up with a more sophisticated diaphragm suspension to avoid the limitations of both the "pinch"-style driver (the original Yamas and all the PMBs) and the "oilcan" or "dome" style driver (all the others, including Fostex), and get back in the business of making a full line, including an all-out signature isodynamic. Heck, I'd be happy if someone made a simple iso with a thoroughgoing design that took some advantage of the dipole nature of the iso driver. I'm not hard to please.

Am I?

.

 

[facelvega]

Quote:

Originally Posted by wualta /img/forum/go_quote.gif Sounds interesting, but we'd have to make it attractive to his company from a business angle...

I get the feeling that the parent company isn't so interested in sinking cash into the headphone branch of MB Quart, judging from the fact that they have dozens upon dozens of US distributors for automotive stereo, but no discernible headphone distributor-- and it's not much easier to find them in Germany. I've even asked them to tell me where Americans could buy their headphones so I might mention it here, but never heard back. Seriously. Moreover, MB hasn't more than refreshed its line for roughly twenty years. Sad, really, since just before that they were outmaneuvering Beyer and Senn pretty handily. And Willi has gone off the map, I'm afraid, though we could probably scare him up if need be.

Maybe Fostex is the better bet. I mean, really they're the Japanese/American MB: a shadow of its former headphone self, just doing limited studio supply production of effectively antiquated designs. Yet they're doing reasonably well and might be cajoled into trying an improved version of something they already own the rights to, especially if we draw their attention to the growing word-of-mouth market for high end headphones, which they're really doing a poor job of exploiting.

The problem is that places like head-fi are a bit too sensational: if you make a big hit for a couple of months with some crafty thread-refreshing and thirty thousand views, that probably amounts to nearly as many extra sales (a la the Vibe), but with less luck and less management, it could amount to nothing. The beauty is they don't really need old-fashioned distribution and marketing to make it happen-- a few findable e-retailers and a good reputation among the enthusiasts should do the trick.

Knowing as most of us on this thread do that a properly modded vintage orthodynamic headphone can easily be made competitive with the current $250-$350 bracket, I think this isn't such a bad idea. I also think that a price around $200 would get them into a lively and lucrative market segment, much more lively in terms of total volume than everything more expensive put together. Heck, if Fostex could do an only slightly improved version of the old T50 for that price right now, they could instantly develop a viable consumer side to their headphone branch without any further ado. It's maddening to think of how this isn't happening.

 

[AudioCats]

My guess is it will be hard to restart the ortho headphones. For companies like yamaha, they already have an existing line of phones, making a new line not only run a risk of inadaquate sales after a big investment (please don't tell me they can just unlock the door of the old YH plant, blow the dust off the old machines, flip a power switch and resume production), it might reduce sales of the existing line. For us we don't give a #$%^ about if their RH line sells, but yamaha probably does, their goal is profit, I don't blame them...
Fostex is even more unlikely. Their T20/40/50 still sell, MSRP range from $120-$199 (though usually sell for half of that). If they go back to the big driver type and raise the production cost, then are they supposed to call the new phones the MKIII with a 50% higher price tag, or call them something else? If they use the same T line model name and call them MKIII, people will listen to the MKIII and realize the current MKII's are junk, so no one will buy the MkII anymore; but the MKIII's might not be impressive to a point that it will compete with other brand/models in the same price range ($100 -$150 can get you some pretty good stuff already, and not everyone fancy the iso technology). If they call it a new name that will require funding to promote it, and still it will kill the sales of existing models.
A feasible way is to get a small high tech company to do the drivers, and out source the housings (SkullCandy Pro DJ housings anyone? come on, they are just like the Ultrasones, why do people crap on the Candy's look while praising the Proline's). Direct sales from the company website, no distributors. For the people who fancy (or curious about) the iso sound, like me, I can see myself spending $200 for a new production model with modern design, durable material, and full size YH-1 or T50 type drivers. The market will be there, but very small, So I'd say limited production first, and make the design upgradable (woody anyone?).

It might work......

 

[AudioCats]

by the way, how is the mids and highs of the T20RP (MKII)? Anybody know?

Bass is a easy problem to fix you know......

 

[wualta]

Quote:

Originally Posted by AudioCats by the way, how is the mids and highs of the T20RP (MKII)? Anybody know?

Haven't heard 'em, but member tyre has. I imagine they're pretty much like the T50RP-- severely rolled off bass, taking a good chunk of the midrange with it.

To give Fostex credit, they're not in the business of making audiophile headphones. That's something they must have learned the hard way when the US pro audio market rejected the T30 and T50 back in 1977. The successful T20 had a shaped response (though it can be modded to counteract this), and so does the T20RPmkII, only much more so. It's the audio tool the biz finds useful.


Quote:

Originally Posted by AudioCats Bass is a easy problem to fix you know......

Yee hee hee hee hee! Hoo hoo hoo hoo! Yar har har har har! If you mean the fish, yes. If you come up with a simple fix for the mkIIs that restores a flat response from them, those of us who are hoarding will break out our hermetically-sealed Zero Halliburton cases and shower you with T50s.

 

[AudioCats]

if the MKII's mids and highs are good, we can add a small crossover and use a KSC35/sportapro/portapro driver as the WOOFER..

... shold be plenty of room inside that T20 case. Set the Fc @500 Hz. The problem is how good is T20's response at 500 Hz?

Since both T20 driver and Koss driver are suppossed to be full-range speakers, we don't need the overkill stuff like 2nd order Xover, just the simplies 1st order will probably be adequate? But if we want 1st order it will be a butterworth (there is no 1st order Bessel I think?), and butterworth distorts phase pretty bad.....

This is not really a quick-fix, but still, doable. The Xover will cause some power losses, but the iso's require powerful amps to drive anyway, might as well crank up that volumn knob...

The T20 MKII's are $30 on ebay, YH-1's (got outbidded on that one

)are like $90, and the T50.....where? don't even see them. If we can make the MKII sound like the YH-1 with $50 ($30 for sportapro drivers and $15 for killer cheap caps to make Xover, $5 for mod material to mount the koss driver) and some work, it might be worth it

 

[wualta]

Quote:

Originally Posted by AudioCats The problem is how good is T20's response at 500 Hz?

The question you should be asking yourself is, "Do I really want to put a crossover point right in the middle of the midrange?" Then there's the problem of iso bass being so much better than the bass from the KSCs (as good as they are).

There's a middle-period T20 on the auction site right now for $17 with three days to go. [UPDATE: They went for $36 shipped] If you can't wait for a cheap YH-1 or YH-100, I'd suggest shooting for that. It sounds okay as is, and you can take both the 'phones and the drivers completely apart. Don't like the factory damping? 7 screws and it's gone. I'd expect Fostex to still stock replacement parts too, should the worst happen. It's not a great iso as-is, but there's a lot of promise there. I'm getting the same model from a fellow HFer and it should be here soon. I intend to try a few... ..things.

 

[ericj]

Quote:

Originally Posted by AudioCats /img/forum/go_quote.gif A feasible way is to get a small high tech company to do the drivers, and out source the housings (SkullCandy Pro DJ housings anyone? come on, they are just like the Ultrasones, why do people crap on the Candy's look while praising the Proline's). Direct sales from the company website, no distributors. For the people who fancy (or curious about) the iso sound, like me, I can see myself spending $200 for a new production model with modern design, durable material, and full size YH-1 or T50 type drivers. The market will be there, but very small, So I'd say limited production first, and make the design upgradable (woody anyone?).

The advantage of convincing Foster or Matsu****a/Panasonic/Technics to get back into the game is that they already have a pretty good design. For their part, Foster/Fostex have little to lose - I don't think anybody is buying the MKII anyway.

They could take the 1977 T50 membrane design, print it on a more modern polymer, and slap it between a couple modern shaped rare-earth magnets, and stick it in a more contemporary frame. Even a vented version of their current frames. Call it a T90.

Technics could do the same thing with the EAH-830.

If we were gonna do this on our own, we'd be up against some patents, probably.

I wonder who we're gonna convince to play along and give us frames. If we could get Beyerdynamic to sell us empty DT-990 frames/cups, it would be Very Very Easy to take a large iso driver and glue it to a disc the same diameter as the beyer baffle. If i could get my hands on a completely blown DT990 or DT880, I'd do this myself with some yamaha drivers. As it is, i love my 990 and 880 too much to make them fosterphones.

But a large, successful headphone company isn't likely to play along. We need someone hungry, committed to staying in the headphone market, who already has a model of headphone that makes an easy target for an ortho retrofit.

Ideally, something totally or mostly open with a giant dynamic driver already in it, or something with a dead simple baffle design.

The Samson RH-600 looks like a good frame, for example, but the stock driver is 40mm. I've never heard these cans, but an electronic musician friend of mine speaks highly of them, and they can be had for as little as $35. They could be the cheapest open audiophile cans on the market, for all I know. Somebody should buy a pair and do some A/B testing between it and a UR40.

I think the biggest problem with manufacturing our own cans for sale, though, is economy of scale.

We'd have to manufacture tens of thousands at a time to get the price down under $500, pretty sure.

 

[ericj]

Quote:

Originally Posted by AudioCats /img/forum/go_quote.gif if the MKII's mids and highs are good, we can add a small crossover and use a KSC35/sportapro/portapro driver as the WOOFER.. ... shold be plenty of room inside that T20 case. Set the Fc @500 Hz. The problem is how good is T20's response at 500 Hz?

I think this would have disappointing results. iso highs are good but not generally fantastic, and iso bass is much better than dynamic bass, when it's there.

If you look at it from a price/performance perspective, I think it would be vastly inferior to a $99 Equation RP-21, and cost you about the same (after all is said and done) + a lot of labor costs.

We shouldn't be encouraging the fostex mkII line anyway.

Now, sticking a KSC75 driver behind the membrane in my pioneer piezo-film cans, that has some potential, and it's likely that, just like a k340, no crossover is needed. In this case especially so, because the pioneer driver presents an entirely capacitative load.

 

[wualta]

Quote:

Originally Posted by ericj iso highs are good but not generally fantastic..

Eh? Aren't the highs on the Maiors up to snuff?

If you crave higher highs, try a reflex disc. I think isos are not quite up to 'stat quality, but with some TLC they can reach almost as high and be just as smooth if not smoother. Just my assertion, and my ears aren't what they used to be, but still...