Orthodynamic Roundup - Page 1391

Thanks for the reply on that

speaking of Fostex Drivers, will whoever outbid me on the Kenwood / Trio KH-83 from the UK please step forward and claim my angst

Seriously though if it was someone in here maybe pop in and give us a glimpse of the innards, pwetty pwease.

SFI transplant part 2 ready =)

might use the white hd25 velour pads because the center hole is smaller than the usual pads, and i have two pairs of it haha

that's going to look really classy in my opinion. Not much depth to those cups it seems like.

yep, thats the problem. but using the d1001 frame is worse, IMO. its hard to tune it properly with those pads, and cups.

Quote:

Originally Posted by nick n 

Thanks for the reply on that

If you are going to thank me for such trifles, atleast do it properly & send a fat cheque my way.

Quote:

Originally Posted by wualta 

Yes, nice to see someone still experimenting with Fostex's big driver-- and getting positive results.

I got back to tinkering them only to adjust to the new pads.The velour pads improve the treble & greatly enhance the soundstage(mostly from the backwave mixing but also from the reduced damping requirements due to better treble extension).

I have ignored these a bit in the recent months partly because I preferred my yammies & partly because they needed a recable.With the new pads & recable these are back to being one of my favorites & will be in regular rotation henceforth.

Like someone pointed out before: the biggest pads and baffles for a 40 mm driver.

It's the Grundig GDHS223, also Pacific Concept, also a Fostex T20 clone.

It's so easy to dismantle, only a screw at the top and the bottom of the cup.

Only damping is a foam pad, disintegrating by age, as opposed to the better quality Yamaha pads that are still springy 30 years on.

Membrane coil pattern seems not as fine as the Yamaha, also substantiated by the 50-55 ohm impedance. Implying less speed, but also greater current ability, for those late ´70s heavy rockers monotoring their upcoming hit at ear splitting levels.

Driver integrated with baffle, just as with the T20.

In this condition - with old, sticky  foam falling apart - sounds a bit bland to me, and I'm not sure a felt damping could do wonders. But I'll give it a go. Pads are in good condition and secured with double sided tape to the baffle, so I don't think there's bass leakage here. Will still put blutak between baffle and cup and see what happens. There's a fine net on the ear side, hardly affects the sound, but the small, perforated baffle might be an obstacle. Does the T20 look the same?

not sure what you mean, here is a pic on T-20

and my t-20's

Does it matter for the holes to line up? I don't think it would make a difference as the pressure should be more or less equalized across the diaphragm surface...

Quote:

Originally Posted by Congo5 

not sure what you mean, here is a pic on T-20

and my t-20's

Quote:

Originally Posted by wualta 

MDR30: my T20's grille (or grill, if you're hungry) looks just like yours-- the @#$% holes don't line up. I don't know if my T20 is as new as Congo5's, since the little "T20" badges are missing. It's a pro audio headphone what don't need no badges, but they tell me that Congo5's is a late model. I do know that the foam pad in the T20 is different from your Grundig's.

Seems the driver is bare on Congo5's T20, no mesh or baffle grille, pure magnet. 'Cause I presume that's the ear side on the first pic?

Quote:

Originally Posted by MDR30 

 

 

Seems the driver is bare on Congo5's T20, no mesh or baffle grille, pure magnet. 'Cause I presume that's the ear side on the first pic?

Yes .. ear side,Yes bare

I got them on ebay ... said new, but who knows..

the T-20's in the other pic have mesh under the baffle.

on top of magnet.

I used the bare drivers in Stax housing which had a mesh.

Quote:

Originally Posted by wualta 
It probably doesn't make a lot of audible difference, but my OCD kicks in when I see the holes not lining up. Just looks wrong.

If anything... I think misaligned holes would actually be better for evenly distributing pressure across the diaphragm. Don't quote me on that though. In a perfect world, everything should be equalized and it shouldn't matter since the diaphragm is assumed to be rigid