Just listened to some Fostex T50RPs today... WOW!
Jan 10, 2013 at 1:50 PM Post #9,841 of 11,345
these keep getting better and better, the more i listen to them and i did just a minor MOD adding akasa paxmate to the cups and plasticine to the baffles!

 
Could you describe a little what you did? I have been considering doing what I think you did.
 
Jan 10, 2013 at 1:57 PM Post #9,842 of 11,345
i added akasa paxmate plus to the bottom of the cups leaving the vents open! then i put some blue plasticine from a german retailer into the baffles, nothing more. and they shine more the more i listen:)
 
Jan 10, 2013 at 2:17 PM Post #9,843 of 11,345
i added akasa paxmate plus to the bottom of the cups leaving the vents open! then i put some blue plasticine from a german retailer into the baffles, nothing more. and they shine more the more i listen:)

 
Thanks for the reply. I misunderstood when I read your first post. You indicated paxmate but I was thinking plasticine. Thats what I didn't understand. Thank you, again.
 
Jan 11, 2013 at 7:25 PM Post #9,844 of 11,345
Quote:
I followed the DBV3 as much as I could and found it to be too tilted towards the top for me.  I could hear why people would like it and believe that it measures well, but for me, reducing the cotton/fiberglass, removing the treble reflector, and punching holes in the stiff felt were necessary for me to get my set to a point where the balance was to my liking.  I have a sensitivity to treble so prefer a warmer signature.  
 
So if it doesn't sound right to you and you have followed the instructions, then it could simply not be the right signature for you.  I wouldn't start thinking something is "wrong."

Same here!

I remove the treble reflector (it's good for some recordings.. not so much for others. with the reflector it's not neutral, but it suits some recordings well.) I also punched 6 small holes in the stiff felt :)

Glad to know we have about the same idea of neutrality fraggler :)
 
Jan 11, 2013 at 7:41 PM Post #9,845 of 11,345
initially i, too, had the same problem using the treble reflector as first described ... too much treble for my liking.  but then i re-worked all of the internals from scratch ... adjusted the amt of rite-aid to use (left out the fiberglass) and settled on the circular reflector & that did it for me.
 
 
Jan 13, 2013 at 8:05 PM Post #9,846 of 11,345
Well I spent the good part of today with the mod and I ended up removing the treble reflector, the fiberglass and the stiff felt. I was even fortunate to find the unobtanium cotton in my local Rite-Aid. I was reluctant to completely remove the felt but it really brought the clarity back that I felt I was missing from pre-mod.  I have no idea how they measure but they definitely sound right to me.  I just did a quick AB test with my UM Miracles and I think these are almost as good.  The bass is still not as deep as I would like but the sparkle is there and now that I am listening to the Miracles they seem a little dull.  It is amazing that a $99 pair of phones can hold their own against a pair of $900 IEMs.  I'm currently driving them with a DACport at about 80%.  I wonder how much better they would sound with a 3+ watt HF amp.
 
 
Jan 14, 2013 at 12:39 AM Post #9,847 of 11,345
Quote:
Well I spent the good part of today with the mod and I ended up removing the treble reflector, the fiberglass and the stiff felt. I was even fortunate to find the unobtanium cotton in my local Rite-Aid. I was reluctant to completely remove the felt but it really brought the clarity back that I felt I was missing from pre-mod.  I have no idea how they measure but they definitely sound right to me.  I just did a quick AB test with my UM Miracles and I think these are almost as good.  The bass is still not as deep as I would like but the sparkle is there and now that I am listening to the Miracles they seem a little dull.  It is amazing that a $99 pair of phones can hold their own against a pair of $900 IEMs.  I'm currently driving them with a DACport at about 80%.  I wonder how much better they would sound with a 3+ watt HF amp.
 

If I was you, I'd go and pick up all the stock they have of that cotton (assuming it IS the unobtanium cotton) and resell it on head-fi. It should sell quickly, and you would really be doing a service to all the people wanting to try it (that is, if there was much to buy up).
 
I don't think you'll get the bass deep enough to match the Miracles without sealing them up and working some magic (whatever LFF does).

I don't think they would get much better with a very high wattage amp, to be honest.
 
Jan 14, 2013 at 10:28 AM Post #9,848 of 11,345
Well I spent the good part of today with the mod and I ended up removing the treble reflector, the fiberglass and the stiff felt. I was even fortunate to find the unobtanium cotton in my local Rite-Aid. I was reluctant to completely remove the felt but it really brought the clarity back that I felt I was missing from pre-mod.  I have no idea how they measure but they definitely sound right to me.  I just did a quick AB test with my UM Miracles and I think these are almost as good.  The bass is still not as deep as I would like but the sparkle is there and now that I am listening to the Miracles they seem a little dull.  It is amazing that a $99 pair of phones can hold their own against a pair of $900 IEMs.  I'm currently driving them with a DACport at about 80%.  I wonder how much better they would sound with a 3+ watt HF amp.
 

 
deadkenny64 I'm not sure, of course, what your standards are for deep bass performance, but I am running a basic "untweaked" DBV#3 using a Project Sunrise II and the low frequencies are quite good. I'm not sure of the exact frequencies, but I listen to a lot of Pink Floyd and Dire Straits and there are a lot of low frequency organs, drums (maybe not so low), and distant rolling thunder. I'm not sure of the specs on the DACport, but I would suspect that it is the culprit. I doubt that it can provide the required current at the low frequencies.
 
Jan 14, 2013 at 10:56 AM Post #9,849 of 11,345
Quote:
 
deadkenny64I'm not sure, of course, what your standards are for deep bass performance, but I am running a basic "untweaked" DBV#3 using a Project Sunrise II and the low frequencies are quite good. I'm not sure of the exact frequencies, but I listen to a lot of Pink Floyd and Dire Straits and there are a lot of low frequency organs, drums (maybe not so low), and distant rolling thunder. I'm not sure of the specs on the DACport, but I would suspect that it is the culprit. I doubt that it can provide the required current at the low frequencies.

FWIW, I'm listening to a tuned DBV #3 (using "Prepared" First Aid Rolled Cotton) paired with my Dacmini (Amp + DAC) and Dacmini (DAC) + Project Sunrise II Amp. Both combinations sound perfect for my ears and preferences. Bass goes very low with "layers" of texture, impact, and speed. I listen to Patricia Barber's "She's A Lady" and "Ode to Billy Joe" and Donald Fagen's "Morph The Cat" for sub-bass and it's there in spades between 15 - 20 Hz.  I listen to Patricia Barber's "Yellow Car III" and Fagen's "On the Dunes" and "Negative Girl" to test treble details that go pleasingly high without sibilance or fatigue. MIdrange vocals and acoustic guitar are full and clear. Soundstage is surprisingly wide for these closed 'phones and imaging is precise. Of course, all of this is IMO and understand that YMMV. I'm very happy with what I hear from this combo.
 
BTW, my Project Sunrise II Amp gets all my playing time because it sounds phenomenal. It performs on par with my Dacmini (Amp section) for 1/3 the cost; of course you still need a good DAC. I've ordered a bunch of NOS and New tubes for tube rolling experiments. 
 
Jan 14, 2013 at 7:44 PM Post #9,850 of 11,345
Ok, so I seem to be getting a bit of sibilance.  Unfortunately, my ears are very sensitive to that and I am focusing on it for every song.  I was trying for more bass so I removed the fiberglass, reflector and felt on the back of the driver and opened the ear cup ports to 1x4 mm.  What can I do to get a little warmth but keep the crazy detail?  The bass seems fine now that I listen but the mid treble is too hot.  I loved the midrange in the unmodified form and I seem to have mucked that up.
 
 
Jan 14, 2013 at 8:43 PM Post #9,851 of 11,345
Quote:
Ok, so I seem to be getting a bit of sibilance.  Unfortunately, my ears are very sensitive to that and I am focusing on it for every song.  I was trying for more bass so I removed the fiberglass, reflector and felt on the back of the driver and opened the ear cup ports to 1x4 mm.  What can I do to get a little warmth but keep the crazy detail?  The bass seems fine now that I listen but the mid treble is too hot.  I loved the midrange in the unmodified form and I seem to have mucked that up.
 

 
I think I would go back to the DBV #3 config and first remove the treble reflector, then test. Then try either additional holes or larger holes in the stiff felt. Last, tweak the cotton thickness +/- 5 mm thickness and try both ways. 
 
Did you "Prepare" the Rite Aid Cotton; no, wait...you have "Natural Absorbent Cotton." So, try 5 mm more vs 5 mm less thickness.
 
You should make only one tuning tweak at a time.
 
I find that once I get the bass:treble "right," the midrange takes care of itself.
 
Hope this helps, and good luck!
 
Jan 16, 2013 at 11:55 AM Post #9,852 of 11,345
So I made more progress and thought they were good and sealed them up.  After 30 minutes or so the treble is still too much compared to the mids and bass.  I don't want to keep opening them (not the screws so much since I used tape; the pads are getting stretched) so I am wondering if less cotton or removal of treble reflector would get me closer to balanced.  I love the sparkle and high extension, I just need to tame the upper female vocal range (Sarah McLachlan high notes seem to pierce).
 
Jan 16, 2013 at 12:37 PM Post #9,853 of 11,345
You can try a piece of micropore tape on the front of the drivers to bring down that treble a bit. It's like a reflector going the other way. 
 
Jan 16, 2013 at 12:43 PM Post #9,854 of 11,345


Here's FR of an mod of one Russian guy. White is unpressed earpads, green - pressed.
Notable is flat FR above 10 kHz.

The mod is very extensive. He picks the drivers, removes stock paper, saws through metal plates, mades wooden earcups no less than 10mm thick, and does custom damping, cup volume matching and earpad matching for each driver till +-2 dB.

I still think that uber-damping is an easier way to achieve flat sound from Fostex. But to get flat FR above 10 kHz, one would have to damp within driver anyway..
 
Jan 16, 2013 at 1:03 PM Post #9,855 of 11,345
Quote:
You can try a piece of micropore tape on the front of the drivers to bring down that treble a bit. It's like a reflector going the other way. 

 
Good idea.
 
I've had good results with a thin layer of cotton, fiberglass, cotton makeup remover pads, or a thin layer of open cell foam over the ear side of the drivers, under the Shure 840 pads' dust covers.  Experiment with type of material, thickness, and coverage area over the driver. Each will tune down the treble in varying degrees. I think I listed this among Tuning Rules of Thumb.
 

Users who are viewing this thread

Back
Top