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

[mrspeakers]

Tdock, no offense but it sounds like you're approaching this a bit randomly.  The foam over the vent works because when the vent is too open, it reduces the backpressure on the driver, allowing the bass to get flatulent.  Everything that is being done in this system is to solve a few specific problems.  However, each piece interacts with others, so you have to be very careful to make one change at a time.  
 
1) Kill plastic resonances: the guys are right.  Blu-Tak helps but is nowhere near as good as dynamat or plasticine at increasing the mass of the driver baffle, which reduces distortion and makes the bass tighter, as well as killing resonances in the cheap plastic baffle.
2) Reflections within the cup.  The raw plastic splashes sound around, which is what makes the stock version sound shouty and murky in the mids.  Akasa solves this.
3) Damping the driver: the stock materials and vent felt were selected to be cheap and to match the characteristics of the earcups without mods, and the pads.  Every mod is different, so adjusting how you damp the drivers is, IMHO, the logical last step.  
4) A useful detail is killing reflections *around* the ear-side of the driver with thick felt or akasa.  
 
 

 

[Anaxilus]

Quote:

Tdock, no offense but it sounds like you're approaching this a bit randomly.  The foam over the vent works because when the vent is too open, it reduces the backpressure on the driver, allowing the bass to get flatulent.  Everything that is being done in this system is to solve a few specific problems.  However, each piece interacts with others, so you have to be very careful to make one change at a time.  
 
1) Kill plastic resonances: the guys are right.  Blu-Tak helps but is nowhere near as good as dynamat or plasticine at increasing the mass of the driver baffle, which reduces distortion and makes the bass tighter, as well as killing resonances in the cheap plastic baffle.
2) Reflections within the cup.  The raw plastic splashes sound around, which is what makes the stock version sound shouty and murky in the mids.  Akasa solves this.
3) Damping the driver: the stock materials and vent felt were selected to be cheap and to match the characteristics of the earcups without mods, and the pads.  Every mod is different, so adjusting how you damp the drivers is, IMHO, the logical last step.  
4) A useful detail is killing reflections *around* the ear-side of the driver with thick felt or akasa.  
 
 

Don't forget selection of the particular size, shape and thickness of earpad.  Earpads maybe one of, if not, the biggest impacts on SQ along w/ the felt before the driver.  IMO.  The rest is more refinement than shaping.  
 

 

[mrspeakers]

Quote:

Don't forget selection of the particular size, shape and thickness of earpad.  Earpads maybe one of, if not, the biggest impacts on SQ along w/ the felt before the driver.  IMO.  The rest is more refinement than shaping.  
 

 
True, the pads have a very big effect, though I'm not sure I'd say it's the "biggest" effect, as every variable effects every other variable.  
 
I have one set of t50s with stock pads.  The interior treatment is the same, and I paxmated the ear-side of the baffle, but the port is wide open.  It sounds VERY close to my unit with the 5000 pads, which has the port 95% closed off.  
 
 

 

[Blasto_Brandino]

I just walked home wearing the T50RP's first, I am amazed how well the Pa2V2 runs them, second they isolate well. If you hear crackling you need to remove the cord from the headset, and apply some Deoxit gold or if you can find it, Nyogel, they need a contact enhancer to be silent. Personally I didn't hear ANY noise from the headset cord connector during the three mile trek after applying the Deoxit. THESE CANS ARE FRIGGEN INSANELY AWESOME!!! AND THESE ARE UNMODIFIED!!! I was thinking about buying the Koss DJ100's but no way in hell could they compete with these!. They are SOOOOOO smooth! and nice and clear, clear treble, clear (and neutral) bass, INCREDIBLE MIDS! I'm DAMN GLAD I bought 2 pairs, when they come up again I'm buying 2 more!

 

[mrspeakers]

Just mod one at a time so you have a reference...  
 
They're hugely awesome to listen to...

 

[Graphicism]

Yeah for that very reason I wish I'd order two pairs... I might undo my mods and start over, that or sell them.

 

[Blasto_Brandino]

That actually was the plan, yeah, it was gonna let me know if the mods were working. I am waiting for the guys next door to dynamat another car, and i was gonna mooch the scraps
 
Quote:

Just mod one at a time so you have a reference...  
 
They're hugely awesome to listen to...

 

 

[mrspeakers]

 
[size=medium]

OMG, these are positively sick.
 
I'm listening to "Love loves you too" by Bruce Cockburn, and I'm just so there.  These are just so dialed in now.  Bass is extended, deep, and extremely tight, without boom.  Vocals are sweet and clean, rich but not chesty, and the treble is bright but not hot.  
 
These still aren't an LCD-2, but they have many of the best attributes; low distortion, tremendous extension, and really clear but not at bright, with a total absence of grain.  
 
The LCD-2 throws a bigger soundstage, and also has more space around the instruments, but they share a sense of "wholeness" to the instruments that is missing in the HD650.  Vocal harmonies just jump out of these suckers, you really do hear layers of vocals that you had no idea existed in the mix.  Again, the LCD-2 out-resolves this, but at 5x the price of my completed units.  For absolute performance the LCD-2 reigns, but for something I'm OK wearing while I wash my car yet totally rocks...  
 
I'm really interested to hear some woodies at our upcoming San Diego meet.
​

[/size]

 

[deadhead12]

Well, I made an impulse purchase the other day and had these up for sale but after reading this thread again I decided to keep em and start modding from scratch.  I bought some akasa finally and went out today and got some plasticine and felt from the local craft store.  With just plasticine in the baffle, some felt over the back of the drivers and a bit of dynamat in the cups these are sounding pretty good.  The presentation is a bit better now and doesn't have that invisible wall thing anymore, I must have done something wrong last time. 
 
I can't wait until the akasa comes in.  I was wondering if anyone has put akasa on the rear side of the baffle, on top of the plasticine or what people's thoughts were on doing that?  Not sure it's necessary but I'm thinking I'll try when the akasa comes, along with the entire cup of course and perhaps the ear side of the baffle as well.   

 

[tdockweiler]

They can (when un-modified). I wouldn't simply just pass on them and they're still worth hearing if you get a chance. They're hardly comparable though since the DJ100 isn't supposed to be neutral, but it's signature is still quite balanced, but not as smooth sounding as say the HD-598. Personally I don't like the T50RP unmodified. Not even remotely, but that's just me. Not saying they're bad.
 
I was about two seconds from throwing my T50RP in the trash yesterday. I wasted so much time on them. Yes, even taking small steps and doing one thing at a time. Almost nothing seems to make my pair sound great. I think I probably spent at least 12 hours on them even with the Akasa foam etc. I probably just have a very, very bad pair. I really will keep trying, but it's gotten to the point where it's tedious to do it anymore and just no fun and more like a chore. It was fun the first...2 hours.
 
I'm sure maybe eventually I'll hear the same sound as everyone else is hearing. I really want to find something better than my DJ100 that's closed. Right now that and the KNS-8400 are my favorites. I may start over from scratch again tonight. Doing small steps at first. It could be that even when modified I'd hate them anyway? I don't think that's possible, but who knows.
 
If I get some extremely good results I'll definitely report back.
Quote:

I just walked home wearing the T50RP's first, I am amazed how well the Pa2V2 runs them, second they isolate well. If you hear crackling you need to remove the cord from the headset, and apply some Deoxit gold or if you can find it, Nyogel, they need a contact enhancer to be silent. Personally I didn't hear ANY noise from the headset cord connector during the three mile trek after applying the Deoxit. THESE CANS ARE FRIGGEN INSANELY AWESOME!!! AND THESE ARE UNMODIFIED!!! I was thinking about buying the Koss DJ100's but no way in hell could they compete with these!. They are SOOOOOO smooth! and nice and clear, clear treble, clear (and neutral) bass, INCREDIBLE MIDS! I'm DAMN GLAD I bought 2 pairs, when they come up again I'm buying 2 more!

 

 

[tdockweiler]

I started over from scratch today after taking a one week vacation from modding these. I was about ready to throw them out the other day because I was so sick of modding them. Almost ZERO of the mod techniques on here worked exactly as they should for my pair. I tried nearly every one of them and took my time.
 
Tonight I used some of the things I've learned while modding my DJ100. I've found out tonight that for me and MY pair, both felt and Akasa foam did squat for me. It made such minor changes that I got rid of it entirely. On my DJ100 it didn't do a thing either (but that's a totally different headphone, I know).
 
Here are the best results I've found yet..remember I tried it all. To the point I got sick and tired of this thing...almost.
 
Staring with a bare headphone with the blu-tack still on the baffle:
 
1) Added a super thin layer of Blu-Tack to the cup (instead of the Akasa Foam, which I found worthless for me).
2) Made sure none of the blu-tack was flat and made lots of indentations in it, even in the cup.
 
At this point I tested the sound and it wasn't that good. So I made the next updates:
 
3) I opened up a car wash sponge (kind covered with fabric) and cut the internal foam pieces into long thin strips. It's the type of foam found in cheap (fake) memory foam pillows.
 
With this configuration:
 
Two on the sides, one on the middle "post" and another on the top of that. Two smaller pieces around the vent.
 
I tested this again and it was much improved. Mids felt neutral and fairly clear, but not good enough. So I did more updates:
 
4) Completely covered the vent with foam and even taped it off. Any super tiny spots that are exposed I added foam to.
 
The change? Everything was now super clear! How I don't understand why, but adding lots of extra foam EVERYWHERE increased the sound clarity and seemed to make the mids a bit more forward.
 
I have this reference song from Utada Hikaru I listen to on my DJ100 that's just goose bump inducing on that headphone. On this it's close to how it sounds on the DJ100, but the mids on this song feel about 5% less forward. I did mod my DJ100 to make the mids more forward though. On this song, my modded DJ100 sounds slightly more clear, but most instruments on the T50RP sound more life-like and accurate. I don't want to bother comparing them since they're both so different. I would like to compare female vocals on each. The mids are now similar though and perhaps my modding technique changes them to something everyone else's T50RP doesn't sound like (worse or better? Who knows. I don't!). Mine feels slightly more forward than neutral, but that's fine with me and how I like it.
 
One thing I should point out is that I never got any good results with the vent open. At one point I did, but it was an awkward configuration. I also was kind of surprised and confused how the more material I loaded up under the earpads, the more clear the sound was?! Right now I'm using felt AND a super thin piece of foam (from my K240).
 
It's so amusing how the more I load up on this magical foam, the more clear and forward the mids are! At this point I won't change them for awhile since they sound good enough for me now. I'll get some better impressions soon.
 

 

[mrspeakers]

I tried Akasa on the rear side of the baffle and the results were awful.  Dead, lifeless and tonally mangled.  Just keep it on the inside of the cup and use it or thick felt on the ear-side around the driver opening.
 

 

[leeperry]

Vocal harmonies just jump out of these suckers, you really do hear layers of vocals that you had no idea existed in the mix

70's jamaican reggae is to die for on this phone...killer thick bass, very clear mids, non-shrill trebles, uber-wide 3D SS w/ the Akasa and sa5k angled earpads....this is definitely the end of the road for me.

Studio 1

 

[leeperry]

I think that's a good example, recorded at Studio 1 in 1977: http://www.youtube.com/watch?v=5he1XPC-Erc
killer bass, very clear and true to life vocal harmonies...PRaT? this phone's got it, oh yeah it does

 

[Mad Max]

 
Quote:

I think that's a good example, recorded at Studio 1 in 1977: http://www.youtube.com/watch?v=5he1XPC-Erc
killer bass, very clear and true to life vocal harmonies...PRaT? this phone's got it, oh yeah it does

You don't know PRaT until you've tried a properly powered SR325is/MS2i. 

 

 

My SR325is has even more soul and PRaT, almost makes me want to sell off all my other headphones every time I put them on. I know I would want a more neutral, peaceful, and analytical sound for jazz and classical, and A2000X has that and is equally as energetic.