Just listened to some Fostex T50RPs today... WOW! - Page 276

100mW min will be ample unless you want to smoke your eardrums.  They can handle way more power than you could tolerate.  I have two 650mW class A amps and neither has any issue with strain at any volume I've attempted.

 

So this unit certainly has plenty of power, but many options exist.  I have an audio-GD 12, entry level unit, and frankly though it has tons of power, it doesn't sound as good as my DACPort with the T50.

Heehee, just tried Tascam DR2d>Pawstex --- not bad.... not bad at all!

Listening to Metallica's Black using full volume - just enough to satisfy me dogears

     Quote:

My post on average_joe's thread:

 

Interested in these mods.

Edited by snakeeater69 - 10/21/11 at 12:16pm

Has anyone tried the HiFIMan pads already?

http://www.head-direct.com/Products/?act=detail&id=111#

BMF 6 v2:

 

I received my shipment of AcoustiPack Lite (thanks AnotherNoob for the link) and wanted to compare it with Paxmate Plus.    

 

EDIT: The photos, below, are of BMF #5. BMF #6 is described in post 3952 at the following link: http://www.head-fi.org/t/452404/just-listened-to-some-fostex-t50rps-today-wow/3945   BMF #6 has 1 layer of Dynamat Xtreme on the ear side of the baffles but it is the same as BMF #5, internally.

 

     CAUTION: Be very careful when removing reflex dots from the white driver felt (or paper). Furniture bumpers from the same package vary in their adhesive strength. I made a small tear in the white driver felt when removing one of the bumpers despite being careful and using my X-acto knife to slowly lift the edges and prise it off.  Luckily, it was no bigger than the end of a ball point pen and located over one of the grid lines instead of one of the openings.  I was able to use a bit of glue to make the repair.

 

Procedures for  BMF 6 v2:

 

 1.  Place Dynamat Xtreme on both sides of the central section inside the cups. Make sure the Dynamat is pressed down firmly and fully attached to the plastic cups.

 

 2.  Apply AcoustiPack Lite over cup Dynamat, cup walls, and the 1" square at the top, opposite the bass ports. Make sure it's pressed down firmly and fully attached to the Dynamat and plastic cups. Leave the central screw compartment uncovered. If you have too much treble, you can later tune it down by covering the central screw compartment with AcoustiPack Lite;. You may be able to "dial in" the treble by covering some or all the central screw compartment.

 

 3.  Leave the  white driver felt in place.

 

 4.  Leave the black bass port felt in place and otherwise uncovered for your first test. You can later tune the bass by covering some or all of the bass port vents to suit your preferences. I like them uncovered except for the stock black felt over the bass vents, inside the cups.

 

 5.  Leave the dust cover over the drivers in place. I previously chiseled off the dust cover surrounding the ear side of the drivers. Some have found removing the dust cover from the ear side of the drivers increases treble and detail.  I did not.

 

 6.  Leave the baffle equalization vents open.

 

 7.  Super mass load the back side of the baffles with plasticine. Do not fill the main baffle equalization vent and the other three semi-open baffle vents with plasticine. 

 

8. Apply 2 layers of Dynamat Xtreme surrounding the drivers on the ear side of the baffles.

 

9. Apply two layers of aluminum duct tape over the second layer of Dynamat.  Note: Here's a handy method for applying this tape - cut to length, position across adjoining sections of Dynamat, and slice away the tape with an X-acto knife by following the curvature of the Dynamat.

 

10. With ear pad removed, make a stencil of the baffle by positioning a clear sheet of overhead projector acetate over the ear side of the baffle. Looking through the acetate, outline the inner oval and the driver square using a magic marker pen. Cut it out and use the acetate stencil to make a stencil of stiff cardboard stock.  Use the cardboard stencil to mark the back and cut out the adhesive-backed black felt, then apply over the Dynamat. Notch an opening for the baffle equalization vents.

 

11. Make cotton gauze "ropes" and place one under the back half of each ear pad. It's a good idea to first tape the back half of each ear pad to the cup to prevent the ear pad from coming off. This is a temporary measure while testing. A semi-permanent solution is to use double-sided tape under the ear pads. SQ can be tuned by varying the length and diameter of the gauze ropes.

 

EDIT: As others have reported, simply lifting the back half of the ear pads may improve SQ and soundstage.  You may be able to reap benefits by tuning the ear pads with gauze, cotton balls, or fiberfill; changing the amount and size of "rope lifters", going only half way around, or differentially lift all the way around the ear pads. 

 

12. Test and tune to suit yourself.

 

 

Comparison Phones - Identical to BMF 6 v2 except for the following:

 

1. One layer of Dynamat surrounding the drivers. 

2. Paxmate Plus instead of AcoustiPack Lite.

 

Results:

 

Careful A/B comparisons were made with SPL matching, lossless files, MacBook Pro, and glass toslink to Dacmini DAC and amp. I really like BMF 6 v1 but BMF 6 v2 has a bit more detail, better vocal clarity, more treble sparkle with air and without harshness, and cleaner bass.  These comparisons are not as specific as my previous comparisons because there are at least 2 variables involved instead of 1.  The noticeable SQ differences of BMF 6 v2 may be due to AcoustiPack Lite, a second layer of Dynamat surrounding the drivers on the ear side of the baffles, an unknown/uncontrolled "Factor X", or the synergy of 2 or all 3. I suspect the main factor, however, is the different acoustic foams used --> Paxmate Plus vs AcoustiPack Lite.

 

Edit: After more extended listening comparisons, I would not say #6 v2 is necessarily better than #6 v1. Instead, v1 and v2 offer different "flavors." #6 v2 sounds crisper while #6 v1 sounds warmer. These differences are slight but noticeable. v2 is heavier than v1. "Pad lifting" is the easiest reversible mod to make. Changing the amount and the placement of padding under the ear pads makes a remarkable difference in bass quantity/quality and treble sparkle.

 

 

Note: AcoustiPack Lite and Paxmate Plus are each 4 mm thick and about the same in terms of ease of application. The difference is that AcoustiPack is heavier due to the constrained layer and purportedly has better sound absorption. Perhaps it soaks up more reflections, reduces standing waves, and further limits the amount of dirty waves sent back through the drivers to your ears?

 

I have some different materials on the way for more experiments. I'll post the results whether favorable or not.

 

 

 

 

 

 

 

 

 

Edited by bluemonkeyflyer - 10/22/11 at 12:18pm

 

I think once you get to a certain amount of power it really gets down to quality instead of quantity. I'm not quite sure what the PPAv2 in terms of power is but my V200 has a lot of it. I think it should have around 2000 mW at around 50 ohms but it does sound better because of a better amp than the PPAv2 but the latter is no slouch.
 

 

I know it's not ideal, but I want to use this amped on the go since I'm almost always in a library studying, I was thinking about getting a stronger portable amp than the E10 I have. I tried opening a threa din the portable amp forums but i've gotten no hits in the last 3 days. I was thinking of getting either a CmoyBB (JDS claims it can drive high impedance dynamics like the 300ohm senns and 250ohm beyers so I imagine it could drive this) or the Little Dot MK1+ which says it has 200mW at 32Ohms so it might output above 100mW wqith th 50 Ohms of these.

Any suggestions, I'm only spending $200 max since I just bought a desktop setup for home.

my fiio e11 off lod from my rockbox ipod is just fine with the t50. it is a bit of a warm amp but the bass is outrageous on anything but 0 eq setting : ]    

 

pictures are fun, here is my setup, which I am pretty fond of. Nice and simple.

 

 

Just to by clear, Rastapants 2 and BMF#6 require the following:

Fostex T50RP ~$75 shipped

Shure SR840 Pads (O2 are better I am not will to drop $150 on pads) ~$18 shipped

Dynamat (extreme?) ~ $15 shipped

Plasticine ~ $18 shipped

Akasa Paxmate II ~ $30 shipped

 

FEEL FREE to suggest alternatives to some of these because some of these stuff are expensive.

Edited by snakeeater69 - 10/21/11 at 12:44pm

I've bought plasticine for about 5 MOD for $5 in Canada at craft store.
 

 

That's interesting how you've put clay even in the surrounding parts that are in contact w/ the cups...this might also improve isolation?

 

atm, I've got newplast in every baffle cavity except for those surrounding parts, and I've got Paxmate inside the cups, but not on the curved walls, really only at the bottom of the cup:

 

My next mod will be about newplast(tungsten putty is only a minor improvement as far as damping factor goes, at the price of an excessive weight) just like you all accross the baffle, and then also in the surrounding parts of the cups. I will use AcoustiPak both in the bottom of the cup and on the curved walls. Of course, I will keep the side vents open and solder the cable directly onto the drivers(I will use joelpearce's trick to make a clean and neat single entry hole at the bottom of the left cup)...it's gonna be good

 

You know, there's a rule on head-fi that the pricier your amp, the bigger your e-penis. Especially when we're all essentially playing around w/ a $74 phone

 

I've tried the T50RP on a number of amps, and tbh even two single opamps w/ a high enough current output drive the T50RP perfectly. OTOH, the T20v2 was another matter altogether, this thing begs for uber juice...it sounded flabby and lifeless off an opamp IME.

I've been lent a vanilla NFB-12(w/o the oversampling jumpers) by our local A-GD importer, it was really nothing to write home to Mummy about...it prolly needed a few weeks of burn-in, though ^^

 

I added the clay in the area that contacts the cup in the RP2 to reduce air leakage, as it's kind of an uncontrolled variable to have no real seal around the cup.  One could also run a bead of silicon around the cup/baffle seam but that's a pain if you keep re-opening.   Seemed a little detail, and was never certain it changed the sound materially.  

 

There are probably many ways to accomplish that end...

^ yep I got the idea from your rasta mod earlier on. it did help "semi-seal" them up a bit and add some weight which feels nice to the touch when handling them.

 

I haven't put paxmate up all over on the cup either since the driver goes as deep as those posts with the foamy jobs on top that push on the driver corners when closed. Also i have enough clay on the baffle that paxmate there would just get squished i think.

 

I am really liking this setup. yea there are a few little things that could change but not worth adding more material anywhere imo. Maybe taking some away ;) cotton that is. Not sure if i'll venture to put fatmat on the front of the baffle?  seems like lots of work for probably not a lot of difference .   who knows, i have a small sheet of it, i may just get nasty and do it.

 

M

 

 

Do a co-op group buy. Ask if anyone has what you need for sale or trade.

4 blocks of plasticine - $4
Felt per sheet- $1
Dynamat - traded for $0
Paxmate $30 - trade or donate what's left
Super Secret Special Sound Stuff by PM Only (Maybe) - Priceless

1. Does someone know if there is a heavier counterpart to blutack?

 

2. How much more heavy is newplast over blutack and how much more heavy is tungsten putty over newplast?

 

I'm not modding the T50RP I'm modding a GMP, but since this thread has a lot of people with hands on experience with putty like materials I thought I should ask here...

For my particular situation the viscoelastic adhesive property of blutack is much preferable over the viscoplasticity of plasticine.

Ideally a heavy viscoelastic adhesive is what I want.

 

3. Does tungsten putty behave similarly to blutack in this regard, or is it more like plasticine?

 

And why are there so few people, if any, using tungsten putty? Shouldn't it's added weight help to damp mechanical vibrations further near the source and further improve sub-bass response?

 

Thanks!