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

[hans030390]

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some sweeps revealed to me that the vicious peaks in my t50rp are at 1kHz. Any specific materials I can try to cure this? It's literally piercing loud at 1k, at least twice as loud as everything else that seem fairly balanced. I have paxmate in the bottom layer of each cup, flush-loaded the baffle with clay, stiff felt with a electrical tape reflex dot underneath on each driver and 80% closed bass port (no felt). earside felt cut away and paxmate donut under some shure pads with lifters. The original stock white filter is gone. My guess is I should try those pop-up sponges mentioned some pages ago if i can find some.

Take 6 regular sized cotton balls, tease them apart, stuff them in the cups (6 per cup). That should solve your problem.
 
I would also suggest removing the stiff felt from the back of the driver and just leaving the reflex dot. It sounded pretty nice that way with the cotton in the cups. I also did not like what the risers did to the sound with the 840 pads.
 

 

[symphonic]

Last night I took some measurements of the driver without cup or pads, both on and off the baffle. I can confirm (up to the rigor of my crappy laptop sound card, my real computer is in Germany) that, with the microphone sitting on the driver, the FR rises up to a peak near 10k and then abruptly drops.
 
I have an idea that I would like you guys to weigh in on. I was playing with the speaker simulator 'Edge'. I put in a square 40 mm driver with a very close mic distance. You get a peak in the treble with an abrupt drop. The location depends on mic distance and exact driver dimensions. A larger driver makes the dip occur sooner. (As per the discussion of the LCD-2 earlier).
 
Do you think that the physical size of the driver and spacing to the ear could be what's responsible for this peak and dip near 10k? If you go to the far field, it's gone (see my far field measurement in the Ortho round up thread).
 
 
 

 

[HDMan]

I have created a monster.

 

[Nevod]

I have a stupid question..
If anyone had heard some of the upper tier electrostatic headphones ( SR-507, O2, HE-60 etc), how do the modded Fostexes compare in terms of detail and bass quality?
I understand that it surely depends on the mod, yet still I'm interested.

 

[HDMan]

Quote:

I have a stupid question..
If anyone had heard some of the upper tier electrostatic headphones ( SR-507, O2, HE-60 etc), how do the modded Fostexes compare in terms of detail and bass quality?
I understand that it surely depends on the mod, yet still I'm interested.

I have ponded the same question, I'll let you know when I get my Stax SR-007 + some rediculously expensive overpriced amp to power it.
 

 

[Nevod]

Quote:

I have ponded the same question, I'll let you know when I get my Stax SR-007 + some rediculously expensive overpriced amp to power it.
 

That would be most interesting!
What is the monster you are talking about?
 
Quote:

Do you think that the physical size of the driver and spacing to the ear could be what's responsible for this peak and dip near 10k? If you go to the far field, it's gone (see my far field measurement in the Ortho round up thread).

Indeed it is possible, 20 db/octave slope?
BTW, try to make 'bass lens' on the front of the driver - a cover of some (not dense) damping material, like the silk coffee filter, with a hole in center. A 15*15mm square hole would be ok, I think..
 

 

[turimbar1]

the fostex has much more bass slam than the vast majority of electrostats, but the electros take the upper end by storm, also the speed and transparency of electros cannot be matched IMO.
 
the latest one, the 009 I believe, handily beats all other headphones IMO, but we are talking 6000 for just the headphone. 
 
really though, the fostex can be very balanced but it cannot beat headphones that are 10x the price imo, which is not surprising. What is surprising is that it can be compared to headphones that are 6x the price.
 
the greatest complement the fostex have ever received was from nerdling, who has the best electrostats. He said he was pleasantly surprised by their balance I believe. That floored me, because he has a very critical ear, he tells it like it is.

 

[Cortlendt]

 
 

some sweeps revealed to me that the vicious peaks in my t50rp are at 1kHz. 

This.
 
Cotton did not help much in my case. Shure pads do something to reduce it though. I'm thinking Acoustipack in cup bottom and tampered plasticine wall around the driver may help but I've to try it yet.

 

[marioman94]

 

Quote:

Take 6 regular sized cotton balls, tease them apart, stuff them in the cups (6 per cup). That should solve your problem.
 
I would also suggest removing the stiff felt from the back of the driver and just leaving the reflex dot. It sounded pretty nice that way with the cotton in the cups. I also did not like what the risers did to the sound with the 840 pads.
 

I tried this before but did not like how much detail I lost. It was muffled or it sounds that way to me. Since I only really use the phones for my computer I just tried dropping a little 1k on the realtek equalizer and this..THIS works very well for me. surprisingly.
 
Also who has tried the Trader Joe's pop-up sponges other than dogwan? I feel like it could be exactly what I need to neutralize these already beastly headphones

 

[HDMan]

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That would be most interesting!
What is the monster you are talking about?
 

The cable isn't the best looking i did, it also has microphonics and the 840 pads are not working out very well for me, there just not sealing properly at the angles I want. Looks like it is another cable replacement and a set of already angled pads, like the JMoney D5000 pads or the Stax SR-007 pads.
 
I am thinking the latter, because at some stage soon I am planning to aquire either a second hand pair or buy new. If I buy secondhand, I will have a near new pair of pads for it, and stick the old ones back on the Fostex.
 
To everyone that really wants to angle the pads on the T50RP (which in my opinion is absolutely necessary, all the top of the line manufactures do this), then do not buy the 840 pads and try and stuff them, it is really a poor way of trying to achieve the desired result.
 

 

[LFF]

Quote:

I have a stupid question..
If anyone had heard some of the upper tier electrostatic headphones ( SR-507, O2, HE-60 etc), how do the modded Fostexes compare in terms of detail and bass quality?
I understand that it surely depends on the mod, yet still I'm interested.

 
http://www.head-fi.org/t/577060/irvine-orange-county-meet-impressions#post_7843631

 

[wdahm519]

Here are the pictures of the Objective2 I threw together last night.  I did the panel this morning really quickly.
 

 

 

 

 

[drexman]

do you guys know of any reasonable priced amplifier that has great sub-bass for the t50rp? mine's lacking sub-bass (20hz - 30hz) and i think it's because of the little dot i+ i'm using right now.

 

[kingoftown1]

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do you guys know of any reasonable priced amplifier that has great sub-bass for the t50rp? mine's lacking sub-bass (20hz - 30hz) and i think it's because of the little dot i+ i'm using right now.

check the post above yours

 
 

 

[mmayer167]

^ ditto. The O2 is seriously a good amp for the t50. Compared to my Lyr the O2 has enough power and only lacks in refinement when directly compared. 
 
I really like that picture second from the bottom wdahm519! 
 
M