xinoxide
500+ Head-Fier
- Joined
- Dec 16, 2006
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well, since my beloved prolines arent working right now, and it seems its going to be a rather long while before i have them repaired/replaced, i figured i would share what i found through expirimentation before their demise.
[size=small]MOD: covering the bufferboard holes ( on stock 750's )[/size]
my 750's came stock with 2 of these holes already covered.
as i uncovered them, i noticed that my low end became louder but seemed to extend a bit higher (keep in mind the "low-mid" dip), maybe leveling out the low end volume with low end extension, this also seemed to widen but raise the low mid dip that alot of you proline 750 owners might know of (try some male vocals, i didnt notice it until i read about it here, and apon listening to a bunch of duets, the problem stuck out like a sore thumb ).
Quote:
[size=small]MOD: opening the earcups
[/size]
removing the "MU metal bufferboard" and taking a look deeper inside the cup revealed to me a cover for the holes that are easily noticable on the proline 2500 and the hfi 2200 headphones.
apon removing the outside "O" sticker, and the inside "O" ring, reassembling and listening, the low end really took over the entire signal that went into the cans to be output by the drivers, problem being, near infinate space for pressure to disperse into the outside world, and the stock proline 750 cups keeping that pressure inside.
Quote:
Quote:
[size=small]MOD: applying prolines vented 2500 pads to opened 750 cups[/size]
without any kind of acoustic dampening, this is still very bery bright sounding, even opens the window for some pretty bad sibilance and timbre issues.
applying light dampening brings it down, and i recommend some expirimentation till its at a good level.
i tried to go even further with this, i borrowed a pair of pleather isolators froma friend with a pair of proline 650's, and i packed the open cups with a medium density pourus foam, i made sure that i could get air and water to pass through this foam before i used it.
i cut out 2 circles, as close to the same size and volume as i could, maybe an 8th of an inch thicker than what i needed.
i was also soldering my cables directly to the drivers at this time, i had finished the right side and was soldering the left when my soldering iron's tip split in half and caused some severe damage to the left driver.
a little bit of single sided listening time on the right side revealed to me that, the mass dampening had killed some of the details that lie underneath some of the music i have, it also killed QUITE a bit of the soundstaging i was starting to love (hand in hand with these minute, low level detail in the recordings ( recorded reverberation = dead))
besides these negatives, a few things i noticed, almost perfect sibilance and timber, though not very loud, these high's were now very smooth and clean and still seemed to ride over everything below it... like, like... im not sure how to explain it exactly, so ill say, it sounded as though it were pretty much brickwalled, but unlike a usual brickwall compressor, they were not pushed to 0db, they were in very natural volume, "riding on the waves of audio" - quote my sister (after explaining that sound is waves, and saying that it sememd to ride atop the lower frequencies)
reverse effects, when i had a smaller but yet pretty well isolating amount of dampening in the cups, and i tried out the vented pads (2500 pads) the low pretty much died out on me.
ill put it down as simply as i can:
Quote:
best scenerio i found (even though i killed a driver) was:
Quote:
the pleather versus the velour is mildly darker in comparison, differewnces here were very slight but still appearent.
i know i didnt get the sound leveled out as i had hoped, but i did make everything sound very smooth and refined in comparison to their stock configuration. more time would have been nice to further my expirimentation with even more typed of foam, maybe even layers of thin sheets of different density foam would have been nice, but now that i have broken one of the drivers, my expirimentation must wait until repaired/replaced.
(ill add pics in the future, after the repair/replacement, and as i go over all of these mods again.)
(if replaced, moving down to the 650/2200 (like the smoother sound of gold a wee bit better, titanium can get too sharp for me))
[size=small]MOD: covering the bufferboard holes ( on stock 750's )[/size]
my 750's came stock with 2 of these holes already covered.
as i uncovered them, i noticed that my low end became louder but seemed to extend a bit higher (keep in mind the "low-mid" dip), maybe leveling out the low end volume with low end extension, this also seemed to widen but raise the low mid dip that alot of you proline 750 owners might know of (try some male vocals, i didnt notice it until i read about it here, and apon listening to a bunch of duets, the problem stuck out like a sore thumb ).
Quote:
example of "the dip"
image thanks to ryumatsuba |
[size=small]MOD: opening the earcups
[/size]
removing the "MU metal bufferboard" and taking a look deeper inside the cup revealed to me a cover for the holes that are easily noticable on the proline 2500 and the hfi 2200 headphones.
apon removing the outside "O" sticker, and the inside "O" ring, reassembling and listening, the low end really took over the entire signal that went into the cans to be output by the drivers, problem being, near infinate space for pressure to disperse into the outside world, and the stock proline 750 cups keeping that pressure inside.
Quote:
example of the holes in the 2500 cups
images thanks to ryumatsuba |
Quote:
example of proline 750-2500 differences
images thanks to ryumatsuba |
[size=small]MOD: applying prolines vented 2500 pads to opened 750 cups[/size]
without any kind of acoustic dampening, this is still very bery bright sounding, even opens the window for some pretty bad sibilance and timbre issues.
applying light dampening brings it down, and i recommend some expirimentation till its at a good level.
i tried to go even further with this, i borrowed a pair of pleather isolators froma friend with a pair of proline 650's, and i packed the open cups with a medium density pourus foam, i made sure that i could get air and water to pass through this foam before i used it.
i cut out 2 circles, as close to the same size and volume as i could, maybe an 8th of an inch thicker than what i needed.
i was also soldering my cables directly to the drivers at this time, i had finished the right side and was soldering the left when my soldering iron's tip split in half and caused some severe damage to the left driver.
a little bit of single sided listening time on the right side revealed to me that, the mass dampening had killed some of the details that lie underneath some of the music i have, it also killed QUITE a bit of the soundstaging i was starting to love (hand in hand with these minute, low level detail in the recordings ( recorded reverberation = dead))
besides these negatives, a few things i noticed, almost perfect sibilance and timber, though not very loud, these high's were now very smooth and clean and still seemed to ride over everything below it... like, like... im not sure how to explain it exactly, so ill say, it sounded as though it were pretty much brickwalled, but unlike a usual brickwall compressor, they were not pushed to 0db, they were in very natural volume, "riding on the waves of audio" - quote my sister (after explaining that sound is waves, and saying that it sememd to ride atop the lower frequencies)
reverse effects, when i had a smaller but yet pretty well isolating amount of dampening in the cups, and i tried out the vented pads (2500 pads) the low pretty much died out on me.
ill put it down as simply as i can:
Quote:
| open (no Dampening) + isolating pads = retardedly boomy open (+/+Dampening) + isolating pads = boomy, can be tweaked further down open (no Dampening) + vented pads = bright open (+/+Dampening) + vented pads = overly bright, tweakable to dark |
best scenerio i found (even though i killed a driver) was:
Quote:
| open (medium density foam damping) + pleather/750 velour pads |
the pleather versus the velour is mildly darker in comparison, differewnces here were very slight but still appearent.
i know i didnt get the sound leveled out as i had hoped, but i did make everything sound very smooth and refined in comparison to their stock configuration. more time would have been nice to further my expirimentation with even more typed of foam, maybe even layers of thin sheets of different density foam would have been nice, but now that i have broken one of the drivers, my expirimentation must wait until repaired/replaced.
(ill add pics in the future, after the repair/replacement, and as i go over all of these mods again.)
(if replaced, moving down to the 650/2200 (like the smoother sound of gold a wee bit better, titanium can get too sharp for me))
