Just listened to some Fostex T50RPs today... WOW!

[Hennyo]

PLEASE do ^^^^ I wanna see the LCD-2 trololol! Haha,
 
I couldn't help saying it!

 

[Rawrbington]

how hard or easy are these t50rps to drive?

 

[Hennyo]

WA3 should be fine. ; ) They're more current hungry than voltage hungry than HD 600/650 according to Tylls graphs. They'll like solid state or hybrids more. Have not heard them on toobs, but I'm sure WA 3 is fine. (not sugar coating anything). I'm not sure how much power the WA-3 outputs as Woo doesn't specify, but I bet you'll be fine. That's a yeasty amp.
 
I did hear the vintage T50 (the ones from the 70's) on a Bijou and it was sweet. Super buttery. Perhaps Wdahm can chime in here.

 

[DaBomb77766]

Well...my E7 appears to be enough to drive them, at least it seems that way to me?
 
Anyway, I've come to realize that my pair is currently missing out a little on the high-end of the frequency.  Excellent low-end and bass, but it just doesn't extend high enough.  I tried EQing the higher frequencies a bit and it helps quite a bit, but I was wondering what mods would help with this?  I tried putting a small square of electrical tape on the back of the driver and it didn't seem to do much...

 

[dogwan]

So I've had a week now to play around with tweaking my mods and I keep coming back to my original configuration.
 
And I've also had the chance to compare them to all my other cans and even though I've always prefered open cans, these just rock. The soundstage is almost on par with an open can.
 
So far I've pitted them against the K701, K401(which I actually like better than the 701's), DT880, and pair of heavily modded Grado SR125i's. Against all of those I found the modded Fostex to be more involving, better at resolving detail, and just way more fun. Admittedly the highs feel a tad rolled off but not enough to make me miss anything. If anything I now realize how my quest for detail has landed me with a collection of cans that are bright and strident. But now I've got the details without the piercing high end.
 
Also as an added bonus I managed to land a NIB pair of HD600's this afternoon and here we have a close match. On my tube amp the Senns definitely excel. However, on my SS amp the Fostex edged out the Senns. in pretty much all areas.
 
I posted earlier about my selection of mods, but I'll re-cap here....
-Recabbled with home brew cable.
-Sprayed Quiet-Kote damping on the inside of the cups.
-Plasticene baffle.
-Reflex dot on the back of driver.
-Cut our stock felt on face of baffle just over driver.
-SRH840 pads.
-Replaced stock felt over cup vents with thinner felt and blocked some vents (I like it with 2 whole slots open).
-Left stock driver damping felt on back of drivers.
-2 mm disc of vegetable cellulose sponge (Trader Joe's Pop-Up sponges) wedged against back of driver.
 
I've tried playing with other materials in the cups (cotton, nothing, polyester, felt) and really have to say I think the sponge with its open cells and random structure was the key. Maybe it's the combination of the damping layer on the cups with the sponge?  Whatever the reason, I am really happy with the sound. While I'm sure they can be made even better, I think I'm at the point of diminishing returns. I am satisfied enough to not risk going to far and missing the mark. It's actually kind of a relief to not dread opening the cups up again.
 
-Dogwan
 
 




 
 

 

[Cortlendt]

I've finally received my Paxmate today so I can mod again. Can't wait for the weekend in the anticipation
 
BMF, have you tried the Kryston tungsten putty yet?

 

[bluemonkeyflyer]

I've finally received my Paxmate today so I can mod again. Can't wait for the weekend in the anticipation
 
BMF, have you tried the Kryston tungsten putty yet?

Yes. See post 4513

Good luck with your mods. Have fun!

 

[bluemonkeyflyer]

Quote:

I've finally received my Paxmate today so I can mod again. Can't wait for the weekend in the anticipation
 
BMF, have you tried the Kryston tungsten putty yet?

 
See post 4513 for details:
 
http://www.head-fi.org/t/452404/just-listened-to-some-fostex-t50rps-today-wow/4500
 
 

 
 
 

 

[Twinster]

Can you please confirm if you have completely removed the felt on the front of the driver baffle including the driver?
 
I'm not that lucky because I still find my HD650 and Ms-Pro to sound much better than my T50rp. 

 

 

 ( mix feeling cause I like those cans)
Quote:

So I've had a week now to play around with tweaking my mods and I keep coming back to my original configuration.
 
And I've also had the chance to compare them to all my other cans and even though I've always prefered open cans, these just rock. The soundstage is almost on par with an open can.
 
So far I've pitted them against the K701, K401(which I actually like better than the 701's), DT880, and pair of heavily modded Grado SR125i's. Against all of those I found the modded Fostex to be more involving, better at resolving detail, and just way more fun. Admittedly the highs feel a tad rolled off but not enough to make me miss anything. If anything I now realize how my quest for detail has landed me with a collection of cans that are bright and strident. But now I've got the details without the piercing high end.
 
Also as an added bonus I managed to land a NIB pair of HD600's this afternoon and here we have a close match. On my tube amp the Senns definitely excel. However, on my SS amp the Fostex edged out the Senns. in pretty much all areas.
 
I posted earlier about my selection of mods, but I'll re-cap here....
-Recabbled with home brew cable.
-Sprayed Quiet-Kote damping on the inside of the cups.
-Plasticene baffle.
-Reflex dot on the back of driver.
-Cut our stock felt on face of baffle just over driver.
-SRH840 pads.
-Replaced stock felt over cup vents with thinner felt and blocked some vents (I like it with 2 whole slots open).
-Left stock driver damping felt on back of drivers.
-2 mm disc of vegetable cellulose sponge (Trader Joe's Pop-Up sponges) wedged against back of driver.
 
I've tried playing with other materials in the cups (cotton, nothing, polyester, felt) and really have to say I think the sponge with its open cells and random structure was the key. Maybe it's the combination of the damping layer on the cups with the sponge?  Whatever the reason, I am really happy with the sound. While I'm sure they can be made even better, I think I'm at the point of diminishing returns. I am satisfied enough to not risk going to far and missing the mark. It's actually kind of a relief to not dread opening the cups up again.
 
-Dogwan
 
 




 
 

 
 

 

[Cortlendt]

 
 

Yes. See post 4513

Good luck with your mods. Have fun!

 
Thanks for the clarifications on mass loading. I'm thinking, you can use something heavy, like small lead balls used for fishing and embed them into small ring of plasticine around the driver? Can you mass load good this way and save cup volume at the same time?

 

[wdahm519]

I think I hit a new level, certainly with detail and separation the other day.  I tried what more or less surmounted to BMF's mid-damped with a little less than half of a triple sized cotton ball (it was very little cotton overall) in each cup.  I had forgotten that I still had SilverStone acoustic foam on the side walls of the cup so I removed that and now I only have acoustic foam on the bottom-most plane of each cup.  I also uncovered all the bass ports because it worked better with this configuration.  
 
I have never heard so much detail in MIDS before.  With headphones like the HD650 with DT990 you could get detail in the highs pretty easily, but the mids sounded kind of blah.  Here the mids sound sweet and not harsh, yet they have lush detail.  The bass is also more detailed than it has ever been.  Its tight and punchy, but super detailed.  Moreover, the highs are incredibly detailed as well.  About as much as the AKG K701's but without the harshness you may find with those.  
 
As for separation, everything has more of a 3D nature to it now.  The Bijou amp helps a lot with this, because I have not heard such good imaging with any other amp.  Nevertheless, there is more instrumental and singer separation than I've ever heard before as well.  I can hear details of background chorus sings being revealed in songs I've listened to hundreds of times before.
 
Overall, I would bet good money that these sound better than an Audeze LCD-2 now, even though I have never heard one.  I wish someone near my owned a pair so I could compare.  I don't want to send these out to anyone...

 

[Twinster]

Good Work!  Are you considering sending your modded T50rp to Tyll at Innerfidelity for the contest?  That way if you win you'll be able to compare the LCD-2 with your Fostex.
 
Quote:

I think I hit a new level, certainly with detail and separation the other day.  I tried what more or less surmounted to BMF's mid-damped with a little less than half of a triple sized cotton ball (it was very little cotton overall) in each cup.  I had forgotten that I still had SilverStone acoustic foam on the side walls of the cup so I removed that and now I only have acoustic foam on the bottom-most plane of each cup.  I also uncovered all the bass ports because it worked better with this configuration.  
 
I have never heard so much detail in MIDS before.  With headphones like the HD650 with DT990 you could get detail in the highs pretty easily, but the mids sounded kind of blah.  Here the mids sound sweet and not harsh, yet they have lush detail.  The bass is also more detailed than it has ever been.  Its tight and punchy, but super detailed.  Moreover, the highs are incredibly detailed as well.  About as much as the AKG K701's but without the harshness you may find with those.  
 
As for separation, everything has more of a 3D nature to it now.  The Bijou amp helps a lot with this, because I have not heard such good imaging with any other amp.  Nevertheless, there is more instrumental and singer separation than I've ever heard before as well.  I can hear details of background chorus sings being revealed in songs I've listened to hundreds of times before.
 
Overall, I would bet good money that these sound better than an Audeze LCD-2 now, even though I have never heard one.  I wish someone near my owned a pair so I could compare.  I don't want to send these out to anyone...

 

 

[dogwan]

Quote:

Can you please confirm if you have completely removed the felt on the front of the driver baffle including the driver?
 
I'm not that lucky because I still find my HD650 and Ms-Pro to sound much better than my T50rp. 

 

 

 ( mix feeling cause I like those cans)


 
 

No, I only cut out the square over the driver. Also I did not remove the screen material on the 840 pads.
 
FWIW, I liked the HD600 better than the HD650 in my limited time with both in hand. Also I found it really depended on the amp when comparing my T50rp's to other cans. In almost every case it was the SS amp that pushed them out ahead. On my tube amp they didn't fare so well.
 
Amps used:
-Matrix M-stage w/ some modding done (op-amps, resistors, caps, etc.)
 
-ASL MG Head OTL (Single ended EL84 based, switchable between transformer coupled and OTL)
 
-Dogwan
 

 

[proid]

Quote:

I think I hit a new level, certainly with detail and separation the other day.  I tried what more or less surmounted to BMF's mid-damped with a little less than half of a triple sized cotton ball (it was very little cotton overall) in each cup.  I had forgotten that I still had SilverStone acoustic foam on the side walls of the cup so I removed that and now I only have acoustic foam on the bottom-most plane of each cup.  I also uncovered all the bass ports because it worked better with this configuration.  
 
I have never heard so much detail in MIDS before.  With headphones like the HD650 with DT990 you could get detail in the highs pretty easily, but the mids sounded kind of blah.  Here the mids sound sweet and not harsh, yet they have lush detail.  The bass is also more detailed than it has ever been.  Its tight and punchy, but super detailed.  Moreover, the highs are incredibly detailed as well.  About as much as the AKG K701's but without the harshness you may find with those.  
 
As for separation, everything has more of a 3D nature to it now.  The Bijou amp helps a lot with this, because I have not heard such good imaging with any other amp.  Nevertheless, there is more instrumental and singer separation than I've ever heard before as well.  I can hear details of background chorus sings being revealed in songs I've listened to hundreds of times before.
 
Overall, I would bet good money that these sound better than an Audeze LCD-2 now, even though I have never heard one.  I wish someone near my owned a pair so I could compare.  I don't want to send these out to anyone...

Can you repost your config? Some pictures will be great too 

 

 

[Twinster]

Thanks Dogwan.  Would it be able for you to post a picture of the front driver baffle without the pad on?
 
Quote:

No, I only cut out the square over the driver. Also I did not remove the screen material on the 840 pads.
 
FWIW, I liked the HD600 better than the HD650 in my limited time with both in hand. Also I found it really depended on the amp when comparing my T50rp's to other cans. In almost every case it was the SS amp that pushed them out ahead. On my tube amp they didn't fare so well.
 
Amps used:
-Matrix M-stage w/ some modding done (op-amps, resistors, caps, etc.)
 
-ASL MG Head OTL (Single ended EL84 based, switchable between transformer coupled and OTL)
 
-Dogwan