[zowki]

Followed these instructions to disassemble the MA900:
http://www.head-fi.org/t/663121/sony-mdr-ma900-appreciation-thread/315#post_9837804
 
Now I'm stuck, not sure what to do next. How exactly do I bypass the resistors? I don't see any jumper/cable connected to the resistors.

 

[Trae]

Can you post another picture without the wires covering the PCB? Although I don't have the headphones yet, I think I can help. Just need a better view of the resistors. 
 
 
EDIT: I think I found another way to do the resistor mod so that it's reversible. I can't confirm it right now, though. You will need a soldering iron. 
 

 
Basically, You're going to remove that clay stuff covering the leads that goes directly to the voice coil, and solder the left channel wire on the side labeled "+", and the left channel ground on the other side labeled "-" You do the same for the right channel. I think you can leave the ground wires stay where they're at, though, since I think they lead to the covered ground soldering connection anyways. 
 
Doing it this way, you don't have to remove any resistors, and you can always solder the wires back in their original places if you want stock sound. I'm not 100% sure this will work, but it should, and I'll try this once my headphones come in later this week. 

 

[Skooter]

This link will also help you. Related headphone and operation.
 
http://www.head-fi.org/t/58234/sony-mdr-f1-fans-86-the-imedance-compensator

 

[Mad Lust Envy]

Anyone know if the F1 pads would fit the MA900? They look more comfy, and probably won't ruin the sound. Wanna see if it's possible to acquire some.

Holy hell, Audiocubes2 sells them for $60 a pair... :eek:

 

[kstuart]

  Are there any photos showing how to open the MA900 and do the resistor mod?
 
These were the only instructions I found but there were no photos. I don't know which part of the MA900 the diagram refers to or how to open the MA900 in the first place.
 
http://www.head-fi.org/t/637267/sony-ma900-vs-sony-cd900st#post_8885894
 
I'm a handy DIY guy and am fairly skilled at soldering so I'd really like to try the mod out.

I would go through the 2 or 3 MA900 threads, and then PM the guys who mentioned that they did the mod.

 

[Amarphael]

  Basically, You're going to remove that clay stuff covering the leads that goes directly to the voice coil, and solder the left channel wire on the side labeled "+", and the left channel ground on the other side labeled "-" You do the same for the right channel. I think you can leave the ground wires stay where they're at, though, since I think they lead to the covered ground soldering connection anyways.
 
Doing it this way, you don't have to remove any resistors, and you can always solder the wires back in their original places if you want stock sound. I'm not 100% sure this will work, but it should, and I'll try this once my headphones come in later this week.

 
It does works just fine and that's precisly what i did, after seeing that the instructions the dude on the 'MA900 vs CD900st' thread left do not match the board layout (as a_rec also mentioned). Measuring the plug resitance afterwards (which of course doesnt amounts to an actual impedance check but just as an indicator) it went up somewhat.
 
Very nice job, I wanted to do this myself but had to trade my pair rather unexpectedly.

 

[Trae]

Alright, that's good to know. It looks like a 5min job, too. The plus side is that you can just do one channel and compare the left (modified) channel and the right (stock) channel to see if you like the changes.
 
I can't wait to get my headphones in now! Since speaker outputs have barely no output impedance, these headphones will really shine when I bypass the resistor circuit and hook them up to the speaker outputs on my receiver (or my FiiO E17). 

 

[a_recording]

  Has anyone tried EQing the MA900? I'm trying to EQ it to get neutral sound and here is what I got so far:

 
You might want to borrow the Goldenears EQ from their Accudio app...

 

[dweaver]

OK quick 5 min listen to a couple of quick song snippets. Initial verdict... damn these are sweet! Q701 for when I need a mid treble feast, these for when I want a warm comfy feast wonderfully enveloping sound that is going to be amazing for genres like Folk/Rock such as Greg Keelor and anything that is atmospheric.

One hell of a deal for the price they are going for!

 

[a_recording]

Thanks for all the info guys. My friends are always interested in getting a pair of MA900's and I was thinking of getting another pair, modding one and then doing a blind test between the two. (With a video of course!) :3

Also dweaver awesome to see you picked these up

 

[kookoo]

Quote:

Thanks for all the info guys. My friends are always interested in getting a pair of MA900's and I was thinking of getting another pair, modding one and then doing a blind test between the two. (With a video of course!) :3

Also dweaver awesome to see you picked these up

 
Friends are always interested in the MA900!!!!

 

[zowki]

Thanks for all the info guys. My friends are always interested in getting a pair of MA900's and I was thinking of getting another pair, modding one and then doing a blind test between the two. (With a video of course!) :3

I'd be happy to mod mine and let you have a comparison. I can save you from having to buy another MA900.
 
So, how exactly do I remove the clay stuff to do the mod? Scrape it off with a knife?

 

[kstuart]

I am finding that the excellent imaging of the MA900s makes instruments sound very natural, because the sense of space around the instruments makes them seem more real.  So, while the "timbre" (balance of fundamental frequencies and overtones) is not quite as good as the Mad Dogs, the superior imaging makes the sense of realism on the MA900s competitive with the Mad Dogs.
 
My choice of which to use, would depend more on the difference between lightweight, cool/airy and "leaky" versus heavier, hot/warm and well isolated, rather than any audio differences.  Even though there are many audio differences, the different strengths are roughly equal.
 
In contrast, the HiFiMan HE-400 lose out in a comparison with either the Mad Dogs or the MA900s.  The imaging and soundstage on the HE-400s are nowheres as good as the MA900s, and the timbre and midrange clarity of the Mad Dogs are superior to the HE-400s.   The HE-400s are the heaviest of the three, and have no isolation whatsoever.   So, while the HE-400s are very enjoyable headphones, they lose out to the Mad Dogs and MA900s for my use, at this time.

 

[dweaver]

These really are light as all get out. I remember reading about the comfort while I was using my Q701 and thinking how much better can they be? But these are on another league comfort wise and I think the Q701 or very comfortable!
 
Just tried some string pieces and these are really nice for violins and cellos. I also tried a choral/operatic piece "Requiem in D Minor, K. 626: I. Introitus: Requiem - II. Kyrie" by "Wiener Philharmoniker, Karl Böhm, Konzertvereinigung Wiener Staatsopernchor & Norbert Balatsch", composer "Wolfgang Amadeus Mozart" and have to say they sound simply marvelous and very enveloping. Then I tried some Hotel California and wouldn't you know it they sounded great there too .
 
Guess I'm grooving out to these a lot.
 
BTW I also received a pair of Sony XBA-H1 today so will do a bit of a comparison between these and the new hybrid IEM and see how they compared to each other.
 
I also have a pair of K545 coming in Friday so I will be a very busy man for the next couple of weeks LOL.

 

[muscleking]

finally got one !!!!. bloody difficult when you are in Canada.
 
$110 bucks. can't complain.
 
yeah it's really good. different sound compared to the ath-ad700. listened to many different music all sounds good. the ath-ad700 is mostly good for classic and vocal. rap and hiphop no good.
 
the bass is very strong vibration can feel the impact of the plastic part on my ears. sounds great out of box.
 
build quality is very fine. comfort yeah. much better than ath-ad700 even. it's not super light. good weight.
 
mine is brand new sealed and box is in excellent condition. well different seller this time lol.
 
here are pics. I have dt1350 too but it's in my office with the o2 and odac.