Just listened to some Fostex T50RPs today... WOW! - Page 261

Can we get a picture of the felt you're using? Or a link! (if a good picture is available) It might be thicker than what we're using and not letting the drivers breathe.

Are you using this felt? Or something thicker? If it's thicker and harder, it may be the culprit.

It is not a bass heavy can with stock pads. Perhaps wait for your 840's to fix this.

So now that I've waken up and no longer as tired I decided to do the other side and imo I did a better job since it is much cleaner inside than before so it doesn't look like a 5 year old did these mods.

I took off the foam inside the cups to start a new:

Then I added some electrical tape over the bass vents and then added dynamat:

I lined the cups with silverstone acoustic foam:

I then added some modeling clay to the ring around the baffle and then put the acoustic foam on the modeling clay except for the additional ring I just put:

I then closed it up and  put foam over the other side of the baffle except around the ring where the four screws which you need to open them up as well as the driver which I forgot to take a picture of (and too lazy to take one now since I put the O2 pads on already) but I ended up with this:

I believe these are all the RP2 mods by mrspeakers. If I missed something please let me know but to my knowledge this is the full mod.

In summary:

I have electrical tape over the bass vents after removing the black felt, dynamat on the lining of the cups and then acoustic foam over that. I also removed the cylinder shaped foam things on top of those 4 tower things in the cups since they were being annoying when I was applying the foam.

I removed the stock felt over the driver and put some creatology felt, filled the holes around the baffle with modeling clay and then put acoustic foam over that and also applied modeling clay to the ring around the baffle.

Lastly after closing it up I put acoustic foam on the ear side of the baffle outside of the ring and where the driver is.

Also I removed the double sided tape (which was a huge pita due to the sticky residue that remained) so that it won't damage my pads like it did with the stock pads when I tried removing it. Some of the pleather is ripped because of that tape.

edit: Actually as I was looking at the pics I realized I put dynamat over the bass vents. Does that matter that much? I think I only did it on the right side but not completely sure. Does that really matter since it's covered with electrical tape and also the foam on top of that?

edit #2: I looked over the posts showing the RP2 and it seems that fatmat was used over all of the lining including the bass ports so I think I'm safe.

I've had almost an hour or so listening to these. I have to say I like what I'm hearing. The bass is much better quality and no longer boomy but that is my fault since I was too lazy to cover the bass vents after taking off the felt and did not have electrical tape then. What I am hearing is something very balanced. It is not analytical and not bass heavy. It is somewhere in the middle being close to neutral with a hint of warmth but that warmth may be due to my V200 amp since that is on the warm side. All areas of the spectrum is nice with the bass being of high quality, mids are nice and no noticeable peaks like before and the treble is much better refined without sounding bright.

I think with these mods I am done modding this headphone. It sounds great and I don't want to mess with it more but I do want to try one more modification after getting an idea from another member here. I am going to try the RP2 more and then try that mod and then see which one to stick. Either way these sound excellent with a nice balanced sound which is what I enjoy. Out of my V200 which has enough power for them they sound great and if I had nothing else I could be happy with just these but I do have other options such as my DT880, HE-4, etc. I like having different signatures for my moods so I won't be selling all the rest of my gear. I do want another pair of the T50RP to configure it to a more bass heavy version but not bass monster heavy. That's the great thing about these headphones is that I can tune it to my liking which I can't think of another headphone where I can do this.

Can someone provide me a picture of the front (ear side) of the baffle without earpad?

rawster, how does your RP2 T50RP sound quality and FR linearity stand against the DT880 and the HE-4?

And is the Yulong D100 able to drive the RP2 T50RP well enough?

Thanks! 

Well, I went ahead and used the thinnest of the felt I got (see my issue above), and it has definitely helped! They sound a lot better now. I also put the black vent felt back and Silverstone foam over 3 of the vent slits. There was still too much bleeding of the bass/lower mids into the rest of the sound, so I ended up covering the last vent slit until it had an opening of about 2-3mm. I also still have fiberloft stuffed under the back half of the earpads (made a huge difference). They sound pretty great now! Can't wait to see what the 840 pads will do...if they sound a good bit better, I'll probably splurge and get the O2 pads.

They're still a bit harsh/bright for my tastes. Need to tame the treble a bit...

My open-backed D2000s still sound more spacious and airy, but I'm having issues ironing out some upper-mid and treble peaks (sibilant and bright). I got them recabled hoping that would help, but it actually made the treble even worse (too exaggerated). It did help out in other areas, though. I'm going to be burning that in to see if it helps. Anyway, it's a lot of fun modding these two headphones! I think once I get my issues ironed out in both headphones, it'll be interesting to see how the two headphones stack up. So far, the open-backed D2000s have more potential to my ears...but perhaps the new earpads for the T50RP will change my mind...

I love my new pants!

I started yesterday and finished BMF #5 this morning. Today, I compared them to Stock, BMF #4, and my Not Rastapants v2. I repeatedly played segments of some favorite tunes across all 4 sets and kept tweaking until I achieved the sound I've been looking for. I'm really happy with the whole sound package. The bass is deep without spill-over into the mids. The midrange is so smooth, clear and balanced with the bass and treble - neither too forward nor recessed. The treble range is extended further than my previous efforts without the least bit of harshness. I can hear chimes, bells, high hats, and brushes on snares/cymbals very easily for the first time out out of modded T50's. There is a greater sense of space between notes and more airiness in female vocals, as well as the treble range, than my previous mods. This modded set's level of detail and clarity is impressive and performs effortlessly. It's easy to tune the bass ports and the ear pads for the amount of bass I want; same for the high end.  And it's all reversible.  

I hope this is helpful....

Cotton balls pulled length-wise, silicone (?) bumpers, Paxmate, Dynamat, Claytoon plasticine. The package of plasticine on the right is unopened, the middle package shows how much was used in one previous set, and the white package is what's left after the current mods. 

Let's begin.

1. Stock driver felt and bass port felt remain in place.  

2. Two strips of Dynamat in cup bottoms, only; pressed down firmly and dimpled with flat head screwdriver. I don't know if this has any effect but I had it laying around.

3. Plasticine applied all the way from the driver perimeter to baffle outer ring. I pressed this in very firmly and tapered outward. I believe the extra mass loading is in large measure responsible for the remarkable improvements I'm hearing as I type this post.  They are not heavy - I split 1.33 oz. between the two baffles but this is 4 or 5 times the amount if you only apply plasticine flush within the baffle compartments.

4. Baffle equalization vents remain open: 1 open through-and-through the baffle and 3 semi-open/covered by the dust cover on the ear side of the baffles.

5. Paxmate cut to fit entire cup interior except the bass ports which remain open --> I did not remove the stock bass port felt.

6. I added Paxmate to the central cup compartment to tune to my preferences.

7. Furniture bumper added to increase treble extension.  This worked great. 

8. Not shown: I pulled apart 4 cotton balls, each forming cotton log. I placed 2 of these under the back half of each stock ear pad and the difference is striking. Reducing or adding more padding changes the external chamber volume with favorable SQ mods to suit your preferences.  

EDIT:   Armaegis suggested using cotton gauze instead of cotton balls.  I rolled up some and pushed them under the stock ear pads. The sound improvement from top to bottom is similar to pulled cotton balls without the messiness of cotton fibers everywhere.

I'm diggin' it.

That's all I have...no secrets...nothing held back.

Cheers

FWIW...

Today I made my first comparison between my BMF #5 and my LCD2 --> Dacmini amp/dac. I tested with Steely Dan, Zero 7, Sade, Anna Maria Jopek, and London Symphony Orchestra - Elgar: Enigma Variations, Brahms: 3rd Symphony, and Smetana: Ma Vlast.  These 2 sets of orthos are voiced very similarly from top to bottom; especially on vocals.  There is less difference with classical.  LCD2's win by a significant margin, particularly for soundstage and air.  Still, for $75 and about $15 worth of mods stuff this mod is ~ 90% of my LCD2's for 1/10th the price...  Impressive Bang for Buck. 

Until someone comes up with a better mouse trap, I think I'm done.  

Next move...wooden cups, T50RP transplants, and re-cabling. 

Yay for the Fostex! @90% of LCD2 - who would complain?