[Faust2D]

Quote:

Originally Posted by mypasswordis /img/forum/go_quote.gif Agreed. T50RP still has more soundstage than most orthos because it is circumaural and the cups are deeper. It can get away with this because the driver is still much larger than the small stuff like the ones in the Yamahas and the SFI drivers, even if not as big as the first generation Fostexen. smeggy has proved that, with enough modding, these will be much better than most other orthos. smeggy, did you make the cups angled on the inside, or are my eyes playing tricks on me? They look very nice, and amazingly quite a bit of it is from the original.

The drivers are actually small in new T50, smaller than all Yamahas and much smaller than old Fostex. Lets do a size comparison of the drivers:

First generation Fostex: T30, T50, T50v2: ~62mm
Second generation Fostex T20 and T40: 45mm
New Fostex T20, T40 and T50: 35mm square driver
Yamaha YH-1, YH-100: 55mm
Yamaha YH-1000: 50mm
Yamaha HP-50, YH-2, YH-3 46mm
YHD-1, 2, 3 and YHE-50: 38mm
ATH / SFI: 38mm

So as you can see new Fostex drives are tiny. I was very surprised how much bass they have

 

[dBel84]

so you're saying that sometimes small is better

..dB

 

[DefectiveAudioComponent]

Now, what we need is a comparison between the Kingwood T50RP and the old T50 king of orthos

 

[ludoo]

Quote:

Originally Posted by Faust2D /img/forum/go_quote.gif The drivers are actually small in new T50, smaller than all Yamahas and much smaller than old Fostex.

Driver length/diameter and area are two different things: a 35mm square driver has a larger area than a 38mm round one. And if the round one has a rivet in its center, the square one has even more "active" surface.

 

[mypasswordis]

I think the driver goes beyond the small square that you see with the stock white damping. Even if it doesn't, a simple area calculation reveals that it is indeed slightly larger than at least the smaller ones (38mm) but yes, smaller than the Yamahas. Interesting, my memory must be off from seeing a YH100 driver.

Edit: ludoo beat me to it.

 

[Faust2D]

Quote:

Originally Posted by ludoo /img/forum/go_quote.gif Driver length/diameter and area are two different things: a 35mm square driver has a larger area than a 38mm round one. And if the round one has a rivet in its center, the square one has even more "active" surface.

Only large YH and HP drivers have rivets, small YHE/YHD drives have no rivets and are very similar to SFI drivers. Keep in mind that large Yamaha drivers are pleated so 55mm pleated drivers have a huge radiating surface.

 

[Faust2D]

Quote:

Originally Posted by mypasswordis /img/forum/go_quote.gif I think the driver goes beyond the small square that you see with the stock white damping. Even if it doesn't, a simple area calculation reveals that it is indeed slightly larger than at least the smaller ones (38mm) but yes, smaller than the Yamahas. Interesting, my memory must be off from seeing a YH100 driver. Edit: ludoo beat me to it.

35mm square drivers are just that, small 35mm drivers, even if a bit larger than round 35mm drivers. 38mm drives in smaller Yamahas and Fostex are probably smaller in terms of radiating surface, but I am not sure how square drivers extrude, that is what percentage of surface actually moves.

What we need for true hi-end is large 60mm new type driver. Now that thing would have bass

 

[Faust2D]

Quote:

Originally Posted by dBel84 /img/forum/go_quote.gif so you're saying that sometimes small is better ..dB

Sometimes, if used right

But a big driver used right.... that's something special

[size=xx-small]Hmmm, I don't like where this thread is going [/size]

 

[mypasswordis]

Quote:

Originally Posted by Faust2D /img/forum/go_quote.gif 35mm square drivers are just that, small 35mm drivers, even if a bit larger than round 35mm drivers. 38mm drives in smaller Yamahas and Fostex are probably smaller in terms of radiating surface, but I am not sure how square drivers extrude, that is what percentage of surface actually moves. What we need for true hi-end is large 60mm new type driver. Now that thing would have bass

Yes, there is no denying that bigger is better, when all else is the same. Well, until you hit a certain point, then it becomes hard to tame.

Edit: Preliminary mod: I lined the backs of the cups with felt, was too lazy to rip off the stock damping, but taped a piece of felt to the funky middle protrusion and taped a reflex dot on top of that. Bass is now no longer farty, and the rest of it is less tubby as well.

Will finish the rest of the mods... eventually.

Edit 2: Note to self: Next step: re-cutting the top vent holes, cutting out only the center of the white damping so I can stick a reflex dot right on, damp the driver slightly more. Figure out exactly how much space is between the funky middle protrusion and the driver. Figure out where this port is so I can plug it.

 

[Faust2D]

Quote:

Originally Posted by mypasswordis /img/forum/go_quote.gif Yes, there is no denying that bigger is better, when all else is the same. Well, until you hit a certain point, then it becomes hard to tame.

Yeah, it seems that 60-65mm is the right upper limit for planar headphone driver. It has to be slightly bigger than average sized ear

to sound good and have nice bass as Stax and Fostex proved.

 

[cetoole]

Is that as big as the high end 'stats get? Dang, I thought they were bigger. My SR404 looks to be about 90mm high, but only half that wide, if I am even measuring the right place. Havnt opened them up or anything, I can just see the red ring inside, and figured that was the outer clamp for the stators. No idea though on the other big stats, ESP/950, O2, or HE90.

 

[smeggy]

Hmmm,

Size is often less important than how you use it

The tiny square driver is putting out as much and as big of a bass as the NAD RP18 and almost as much as the T30 so it's no slouch in the bass department and that's with circum pads. No mean feat for such a small thing once everything else is right.

The phones I have with the most bass of all are a crazy little set of SFI's.

 

[cetoole]

Smeggos?

 

[wualta]

Quote:

Originally Posted by smeggy /img/forum/go_quote.gif Morning time and they're still awesome.

This is an excellent test. For lots of things. Some of which we won't get into here.

Thanks for the good-quality photos, Smeggy. I don't know how many people will be willing to free this driver from its plastic prison, but you're right, the only way to get at all of its potential is to get out the saw or dremel-type tool and cut it out and transplant it.

Is what we see glued together more or less permanently? Would you say it'd be easy to design for screw-together construction?

Quote:

Originally Posted by smeggy /img/forum/go_quote.gif The housing is thin live plastic with no damping/absorption inside...

Not quite, since there are those rubber pills, if your cat doesn't eat 'em. But this is like saying the damping on the Pro 30's drivers was adequate. They certainly thought so.


Quote:

Originally Posted by Faust2D /img/forum/go_quote.gif ..if only you can add realistic soundstage to this mix....

That's the next frontier-- stealing ideas from AKG and letting midrange backwave through special baffle vents. Or building up so much excess bass that we can get away with porous earpads. If someone builds an ortho HD 414, but with flat FR and good bass, I'll be a very happy guy. Heck, I'll settle for an ortho ECR-500 (sorry, F2D-- I know it's a sore point).


Quote:

Originally Posted by Faust2D1 Secend generation Fostex T20 and T40: I think are 38mm

They're 45mm. About HP-50 size.


Quote:

Originally Posted by mypasswordis Yes, there is no denying that bigger is better, when all else is the same. Well, until you hit a certain point, then it becomes hard to tame.

Sort of. When the driver is big enough to support an audible frequency on it as a standing wave, you start having problems, but even so, a good ortho could be very big and still sound good-- it would just weigh a ton.

But we shouldn't be surprised that a small driver with area roughly equivalent to the 38mm SFI driver has bass. At rest, the Fostex driver has ~8% more area. At rest. At max excursion, the diaphragm starts to try to form a dome, which will tend toward a circular shape, so I've always made the casual assumption that the dome from a square driver would be the size of a circle inscribed inside the square, making it smaller than the 38mm round driver at max excursion. I could be wrong. But either way, they're close. Fostex's problem was reducing the size of the driver, even though they gave it those wonderful magnets, while actually increasing the earcup volume. Argh.

Quote:

Originally Posted by mypasswordis I lined the backs of the cups with felt, was too lazy to rip off the stock damping, but taped a piece of felt to the funky middle protrusion and taped a reflex dot on top of that. Bass is now no longer farty, and the rest of it is less tubby as well.

Hey, all right! Sounds good; simple; takes care of the important stuff. For the typical owner, this or something very like it will be the mod.

 

[mypasswordis]

I see, so it ends up still being smaller than the rest.

A few questions for further modding: Where is this anti-fart port? And do you think cutting a hole in the fabric covering the front of the drivers would help clarity/treble?

I probably used the most crude possible way of remaking the holes in the vents: slicing holes with a pocket knife. Only did it to one side, but it seems that it further helps tame nasty resonances from the backwave, and I might as well do it to the other side now.