[chrislangley4253]

Quote:

Howdy gang, it's been a while. 
 
I've been listening to the T50RP for the past week or so, and they sound pretty good with the amp I'm borrowing (I'm personally holding out for the O2, so I don't have an amp atm). There are some blatant issues though. For better or worse, I've damped the interior with dynamat that has the foil pulled off, and have cut the felt from the front to give it some much needed clarity. 
 
First off, they sound muffled as hell.  The frequency response is similar to the HD650, but the HD650 sounded much clearer. This might be because they're overdamped or just because they're closed. Any ideas on what to do from here? I don't have any felt and have no way of getting any. Would a cut up sock work?
Second, the cable jack is the worst I've ever experienced on a headphone. The right side cuts out and only excessive wiggling fixes the problem, only to have the right side slowly get quieter and cut out again. What the hell, fostex? I guess I have to recable these now.
Third, these pads suck. They're not deep enough and they can't stay on without tape. Even with tape, they still come off. I've given up on them, and they no longer give a seal and are resting on top of the driver(not taped down, just held on by force against my ear). I only remember the stax pad as an alternative, and I think it is beyond ridiculous to spend that on these headphones.
Fourth, this headband sucks too. It's not as bad as the grados, though.
 
Now, some questions. 
 
I've put my fingers over the back vent, and I didn't notice the frequency response changing, however it isolated better. There's no issues in filling this hole, correct? 
 
Is paxmate supposed to be an alternative to the felt? Does anyone in the greater Dallas area have some they wouldn't mind letting me have?

Some deoxit will clean out the headphone jack and have it working good as new. The paxmate works really well inside the cuops. 

 

[cya147]

Yes i have but the 668b was not burned in (50 hours max i guess). IMO t50rp (stock) was more superior than 668B (stock) in all aspect (such as transparancy, speed, bass extension, instrument separation, and so on) except soundstage. Stock t50rp have narrow soundstage so IMO it is not fit well in orchestra. I find change the earpads and/or recable with the right plug can make the sounstage wider.
 
I agree that 668b is a nice headphone for the price but IMO it is a no contest especially if you pair t50rp with the right amp (an amp that can give a lot of current).
 
 
 
 
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Anyone here have experience with these and the Superlux HD668b care to comment on both?

 

 

[Reticuli2]

Stock, they drop off at 13khz and over, but the rest doesn't seem muffled to me.  Bass is rounded and rolled off, but that doesn't produced "muffled" exactly.  There does seem to be something missing to my ears that eq compensation still doesn't fix and I can't put my finger on, but that's without a good amp.  Isn't the T40rpmk2 a closed version of this?  I would think just sealing the vent would produce similar sound, no?  I wonder if you're hearing the resonances people talk about combined with the lack of extension up top.  I'm not sure how some of the people who've successfully improved the sound damped their headphones.  So hopefully they can help. 
 
As for the cable, I put some rubbing alcohol on the jack and an alcohol swab on a rod and worked it in there.  I'm not sure if it was the alcohol or the covered rod pushing onto the top clip that made the difference.  The rod/swab combo wasn't going very far in, so it was pushing up against the first clip I think.  Anyway, it seemed to have fixed the right dropping out on me when I first put them on.  Crazy, slow hypnotic volume reduction occured on the right after the first minute of listening to them on a Cowan U5.  I thought the load of the headphone was causing the player to malfunction.  So it's definitely a fouled up jack design.

 

[Reticuli2]

What are some cheap high current amps?  I'm hoping Tyll's impedence curves show some serious requirements in the frequency extremes on this.  Actually, wouldn't the modded ones show the exact same characteristics?  Scratch that... gonna go look.
 
No, it looks even at 55ohms across.  Darn.  If it had some big slopes in the extemes or phase overlaps that might be something that could be fixed by just the amp, right? Don't see anything like that.
 
The Superlux all have the edge on high frequency extension.  The Fostex stock has a total lack of.
 
Quote:

Yes i have but the 668b was not burned in (50 hours max i guess). IMO t50rp (stock) was more superior than 668B (stock) in all aspect (such as transparancy, speed, bass extension, instrument separation, and so on) except soundstage. Stock t50rp have narrow soundstage so IMO it is not fit well in orchestra. I find change the earpads and/or recable with the right plug can make the sounstage wider.
 
I agree that 668b is a nice headphone for the price but IMO it is a no contest especially if you pair t50rp with the right amp (an amp that can give a lot of current).
 
 
 
 


 

 

 

[CYoung234]

If anyone has some Dynamat they would like to trade for some PaxMate, please PM me. I have several full sheets left.

 

[chrislangley4253]

Quote:

If anyone has some Dynamat they would like to trade for some PaxMate, please PM me. I have several full sheets left.

PM'd.. You can keep the paxmate.. But, I do have some dynamat for you. 

 

[200poundsofamp]

Quote:

Third, these pads suck. They're not deep enough and they can't stay on without tape. Even with tape, they still come off. I've given up on them, and they no longer give a seal and are resting on top of the driver(not taped down, just held on by force against my ear). I only remember the stax pad as an alternative, and I think it is beyond ridiculous to spend that on these headphones.

SRH840, SA5000, and GMP pads seem to be the other options.
 
I really recommend the rx900 pads though. I took a risk and bought some based on how well the rx700s fit, and they're fantastic, they fit better, are more comfortable and sound better than the stock pads. I've tried the 840s and they me a warm sounding slurry, but mrspeakers seems to have gotten really good results with them so I guess they can be worked around. The rx900 pads though are a drop in replacement sonically for the stock ones. More expensive at $30 at the JVC website if you use a code, but I think it's well worth it. You need two of these, then use the code JVCPROMOSHIP712 for free shipping.
 

 

 
Quote:

First off, they sound muffled as hell.  The frequency response is similar to the HD650, but the HD650 sounded much clearer. This might be because they're overdamped or just because they're closed. Any ideas on what to do from here? I don't have any felt and have no way of getting any. Would a cut up sock work?
Second, the cable jack is the worst I've ever experienced on a headphone. The right side cuts out and only excessive wiggling fixes the problem, only to have the right side slowly get quieter and cut out again. What the hell, fostex? I guess I have to recable these now.

Now, some questions. 
 
I've put my fingers over the back vent, and I didn't notice the frequency response changing, however it isolated better. There's no issues in filling this hole, correct? 
 
Is paxmate supposed to be an alternative to the felt? Does anyone in the greater Dallas area have some they wouldn't mind letting me have?

 
Akaska kills the muffled sound, and 1/16" stiff felt glued over the white membrane on the back of the driver brought out the treble a little for me. The vent tunes the bass, rip off the foam over it and use electrical tape, this is my setup:
 

 
You can open up more than that for more bass. Closing it up completely didn't sound good, I think the drivers need a little air at least.

 

[BobSaysHi]

^ thank you very much for your responses. I read through my post again and it came of more critically than I intended. I guess I was kinda angry at the left side cutting out.
 
I used isopropyl alcohol and cleaned the contacts and it is much louder on the right side (most of the time). I'll give it another go tomorrow and see if I can completely fix the problem.
 
Those pads look nice, and like it would completely fix my fit problem. Are they any deeper than the stock pads? I need like a centimeter more length so my ears don't touch the driver.
 
I'll try and get some felt soon. Or find some somehow.
 
EDIT: so I went ahead and tried taping up the hole. The bass is a little bit less... uh floppy, thanks

 

[200poundsofamp]

They compress a little more than stock, so on your head they're slightly deeper, and I don't know if it shows up in the pictures but they're actually angled a little. Nice and plush though and they get a really good seal which the drivers seem to need.
 
Yeah it's frustrating, but one you get the sound dialed in they're pretty sweet!
 
For the bass, dynamat or modeling clay on the back of the baffles cleans it up even more, like this:
 
The felt on the driver helps too, but you might want to save that for last, you might like them without it. You can either glue it on around the edges or tape it, important thing is you still want air getting through it.

 

[mrspeakers]

Now, some questions. 
 
I've put my fingers over the back vent, and I didn't notice the frequency response changing, however it isolated better. There's no issues in filling this hole, correct? 
 
Is paxmate supposed to be an alternative to the felt? Does anyone in the greater Dallas area have some they wouldn't mind letting me have?

The vent tuning becomes more of an issue once the white felt is removed. When it is off, the driver is significantly less burdened by back pressure, and bass increases radically.

At that point, changing pads and adjusting the vent size has a major impact on bass. With the vent fully open it is incredibly bass heavy. Mostly to completely closing the vent will result in powerful bass without boom or a massive mid bass hump.

With my O2 pads the vent is down to about 2mmx2mm, for the 840 pads it's about 4x2. I am playing with closed soon just for giggles.

 

[cya147]

From the spec only, you may take a look at t amp. Basically, it is a modified D class amp from Tripath company. FWIR, the one build by Topping do some justice with lcd 2 rev 1. You can find one on ebay.
 
FWIR, a right amp can do justice on high frequency just like hd650 case. I have been used a bright amp so i am not having problem with high frequency extension. 
Quote:

What are some cheap high current amps?  I'm hoping Tyll's impedence curves show some serious requirements in the frequency extremes on this.  Actually, wouldn't the modded ones show the exact same characteristics?  Scratch that... gonna go look.
 
No, it looks even at 55ohms across.  Darn.  If it had some big slopes in the extemes or phase overlaps that might be something that could be fixed by just the amp, right? Don't see anything like that.
 
The Superlux all have the edge on high frequency extension.  The Fostex stock has a total lack of.
 


 

 

 

[leeperry]

 
What are some cheap high current amps?

You know, the T50RP sounds just great w/ 25mA...it's got a low impedance and a fairly high sensitivity, it's not a starved HD650 by a long shot.

 

[Reticuli2]

Those Toppings are speaker amps with headphone jacks on the front, right?  Don't really need the speaker amps.  Are the headphone jacks run by the class d amps inside?  And any idea of the output impedance on these jacks?  You're right, though, I forgot that the class d stuff is regarded as bright and lean but in a good way.

 

[cya147]

I've tried a few amps with lots of power and i can tell you t50rp does take benefit from this kind of amp so IMO try to consider t amp if you can afford it. I personally haven't heard topping amp so i cann't tell how does it sound. I've no idea about the rest of your question.
Quote:

Those Toppings are speaker amps with headphone jacks on the front, right?  Don't really need the speaker amps.  Are the headphone jacks run by the class d amps inside?  And any idea of the output impedance on these jacks?  You're right, though, I forgot that the class d stuff is regarded as bright and lean but in a good way.

 

 

[Reticuli2]

 
[size=10pt][size=10pt]My understanding is low impedance cans need more current while high impedance ones need more voltage. Maybe that's wrong. Maybe it’s the phase thing in the impedance plot that dictates that. More's not bad, though, regardless. I'm just looking for some good quality amps that are fast and near-zero ohm output. All my headphones are 100ohm or less. [/size][/size]
[size=10pt][size=10pt]I'd prefer something with a built in DAC as my Compaq CQ56, though it does have an o.k. jack on it and I've got an equally competent Syba USB thing that sounds different but good with the Fostex, I'd like some D/A conversion with more pedigree. I have no idea how the laptop's DAC or the Syba measure since I don't have any quality input capability to test them with Rightmark. Some other source of known performance would probably be a better option.[/size][/size]
[size=10pt][size=10pt]Anyone else notice that ambience and low-level detail retrieval seems to improve with burn in on the Fostex driver? It previously did not startle me with extreme side imaging that seemed to come from far off. After playing a lot of pink noise (I don't have the XLO disk with me) for a few nights, it's been kind of freaking me out. Maybe I'm doing something different or it's just placebo effect. But getting startled increasingly from them does seem pseudo-empirical. That wasn't happening before, and it even had a lot missing at first. As I'd said, it was hard to explain what it still lacked even after eqing. This change could certainly be my brain “adapting” to the sound that Tyll talks about, but I haven’t been listening to it much in the past few days as it was running the pink noise.[/size][/size]