[Hawaiibadboy]

checking in.
i just removed the felt on the drivers and ou boy - i dont think i need to do the resistor mod anymore

Hey i know you...seen you around

I have had time to consider the question a poster made above and if I had to pick the 900 or Z7 it would be the 900. I respect smokingman and his opinion is well put and tech accurate but the analogue wide sound of the 900 is kind of addicting and need it in my life good

 

[dogears]

heya hbb

 

[dogears]

replaced the pads w shure pads. its even better now

 

[dogears]

i wonder if there are 2 versions of ma900. based on rinchoi's posted pic (most probably from the net) - the felt hole is a lot bigger than what i have.

 

[thesmokingman]

checking in.
i just removed the felt on the drivers and ou boy - i dont think i need to do the resistor mod anymore

Do you mean the bass lens?

 

[dogears]

yup

 

[dogears]

superlux pads is working best for me right now

 

[thesmokingman]

yup

If you like that mod, you should try removing the whole foam/felt pad. For me at least it restores all the mid and upper range weaknesses. After removing the foam pad, I replaced the bass lens and put the speaker grill cover back on. I had moved to a 400i for daily use, but now I feel the 900 is no slouch in the midrange dept and it feels like the bass is stronger so its the 400i that is back in storage. The foam damping material absorbs a larger slice of the frequency range vs just the low end. I'm still trying to wrap my head around why they designed it with sooo much padding on top of the driver. The bass lens I understand as that focuses the bass but the rest of that padding... does not compute.

 

[dogears]

i'm not buying the bass lens, it just muffles the sound. and the stock pads - it definitely has to go as well. bass/treble on mine's not (so) rolled off anymore.
it's definitely holding its own against NH and hd800.

 

[thesmokingman]

i'm not buying the bass lens, it just muffles the sound. and the stock pads - it definitely has to go as well. bass/treble on mine's not (so) rolled off anymore.
it's definitely holding its own against NH and hd800.

Nah, I'm not talking about the pads. I mean the pad covering the driver that is double sided taped onto the driver cage. That's the thing that the bass lens is applied to. And the bass lens is real, they've been using it since the MDR-F1, of which the MA900 is an evolution of. *And I agree some of the design decisions don't make a whole lot of sense like the compensation circuit, the crazy thick driver pad, etc but it is what it is, shrugs.

Just think about what that thick pad, lined in double sided tape and felt does to your mid and upper range!

 

[dogears]

augh, i cant upload pics right now. i left the foam (but w 'holes') where the felt(bass lens) was glued on. i dont think its affecting the sound anymore.
what was the hole size on your felt(bass lens)?
i'll play around w the hole size when i get the chance.

 

[thesmokingman]

augh, i cant upload pics right now. i left the foam (but w 'holes') where the felt(bass lens) was glued on. i dont think its affecting the sound anymore.
what was the hole size on your felt(bass lens)?
i'll play around w the hole size when i get the chance.

I removed the whole foam pad and pu the bass lens back on. The bass lens is acoustically transparent to the upper range, but not to the lower range. Essentially the bass lens is a low pass filter, allowing midrange and higher to pass thru while focusing the bass to the center of the driver. I can take a pic if you want to see the mod.

"On the front side of the driver unit of the MDR-F1 is an "Acoustic bass lens", a box shaped chamber covered by an acoustical resistor material. The acoustical resistor material allows high frequency sound to pass through and filters the low frequency sound. Consequently, the low frequency sounds are concentrated to the center part of the driver unit, and sufficient bass sound is delivered to the listener. At the same time, frequency response is controlled by the "Acoustic bass lens" to provide mild yet extending high frequency sound."

 

[dogears]

yup, i've read that on rin choi's page but i still dont buy it based on what i can hear. and i'm intrigued on the picture on that page:

(if this is ma900 driver) as mine has smaller holes.
better if you can post pics. i'll post mine when i get home.

 

[thesmokingman]

Mine has a oblong opening which the lens replaces with a penny size hole.

 

[dogears]

i dont have that 'oblong' opening:
(i hope you see the pic)