Oppo PM-3 disassembly (mod maybe?)

@Tyll Hertsens said the PM-3 couldn't be disassembled without permanently damaging any part of it.

But I was able to disassemble it anyway...

Foam piece: yes, you're looking at the underside. It is possible to peel this off without permanently damaging it... if you're careful enough. But you don't have to be afraid of hurting the foam piece either. Re-application is also possible afterward


Plain baffle without foam: just unscrew it. The front foam was the hard part.


The inside: damped to death with wool felt... which is cool and all but I feel this is muffling too much of the sound. Specific placement of this may help, though, since you do want this for its ability to absorb anything >1KHz.


Grid pattern on ear cups... which are awesome acoustic absorber for high mids. I think I saw this in the MDR-Z7 as well, and it does a marvelous job of absorbing high mid on both headphones.


Back of driver: black thing is glued-on paper, which absorbs high mid, yet again. It seems like there's a theme, right?


And just cuz I'm crazy, I went one step further and removed the paper just so you can see bare driver underneath. This is likely irreversible, but I have found a reasonable replacement for this paper (I think).


Anyway, this isn't a mod guide, but more like a proof of concept that you can totally disassemble the PM-3 without permanently damaging anything.

@Audio Zenith, this is me cuing people to the fact that you are probably hiding a secret closed-back PM-X project.

As for the rest of ya'll who own a PM-3, and you want to mess around with yours, here's the "push". Go to town! This one is very moddable, and since the driver is better than T50RP, I think some amazing things can be done to it.

Will post a how-to to "disassemble" and "reassemble" the ear pads whenever I have moar free time. But if y'all are eager to know, you can use "leather glue" to accomplish that.

 

I'm interested in what you can get out of these. I heard the PM3 at the AZ meet and honestly it was one of my favorites. Overall cohesive frequency response with some upper mid suck out, which makes for a more relaxed listen with a little peak around 8 kHz. Contemplating getting these for my bedroom rig.

 

Would definitely be interested in seeing more. Since I have wanted to get a pair of end game closed portable cans, the PM3 has been at the top of my list, but I've held off so far. Tapping into these suckers to get more out of them could get a purchase from me.

 

Interesting. But much more money than the t50rp.

 

Well, I have honestly "done things" to this one... and I have gone pretty darn far as well, and I can tell... that it does have a lot of potential for re-tuning.

The effort will be quite monumental, though, as the shell leaves no room for air, so you either have to drill holes (fugly!), or play around with rear damping in order to bring out lower frequencies.

I actually hear this one as having a downward slanted slope, but then somewhere along the upper mids, it kinda rises up a little, and then after that, there's a weird "peak" probably at around 8KHz or slightly lower that augments the peak ealier and prevents this headphone from sounding completely laid-back.

The "peak" doesn't want to go away from what I've tried, although giving some "air" to the rear of the driver does help mitigate it, so there's hope for a perfectly smooth response.

Anyway, what I've known so far is...

1) The front foam piece increases bass by a small amount. It's mostly there to "cushion" your ears. If you don't like an "on-ear" feeling from these headphones, you may remove it and use some kind of paper as its replacement (make sure to cut to the exact same shape).

2) The "notch" in front of the driver focuses midrange. If you remove it, things will sound a bit more airy at the expense of sounding slightly more shouty. I'd personally leave it alone because removing it is a pain in the rear, and you still have the "dome" thing in the middle.

3) Stock rear damping material is a bit deafening/stuffy, but is very effective at reducing upper mids. It is advisable that if you want to change back damping, you should try to keep a part of this material around.

4) If you don't want to access the inside, you can still roll pads by... destroying your pair of stock pads to salvage the plastic rings. The rings themselves help give some distance with the pads and increases bass. Oh, and any ear pad that fits Audio Technica ATH-M50 will potentially fit on the PM-3 as well, so... go do some experiments?

5) I don't think I'll post a mod guide for this one any time soon... mainly because it's a bit more complicated and involved than I'd like. In the past, I'd post more complicated mods, but not now. I'd prefer to post when there's something super simple that can be done, and can yield a massive improvement. So for now, this post remains a disassembly rather than a "mod" per se.

6) This headphone is indeed more expensive than T50RP, but you're also paying for the styling and construction, on top of the super nice drivers. T50RP is cheaper, but not by much (consider Mk.3 prices). It's also not as portable. The drivers are also not this nice... (stronger bass, more impactful, smoother midrange, etc...) by default. And if you don't want to spend a lot of time tweaking, what you'll get out of that thing is mediocre, whereas the stock PM-3 already is pretty close to an ideal target.

 

Well I'll be sticking for my t50's because I got them for $75 used, and they are almost perfect now. I increased treble, now I just need to increase my bass. Going for a Grado sr80e sound signiture, because I like that.

 

The PM-3 might actually be the best measuring and sounding closed back I've tried. Then there's the fact that it's built with Apple-like attention to details.

I'm probably writing a review next week.

 

Oh, yeah.

Honestly, if you just want something that's portable and "just works", I'd advise anyone to grab a PM-3 and then forget about everything else. It's just that freaking good!

The drivers are capable of more bass than stock, too, by the way, if you even want that. Oppo is, in fact, "limiting" the bass output already in its base form.

 

"f**k," said Pooh.

We probably all fit into at least one of those categories. I can shave my head and remove my glasses, but I'll still be a potatohead. We're doomed.

I secretly want to listen to a pair, anyway.. are they good enough stock to be a good daily commuter headphone, or are people itching to wring more bass from them?

 

Hrm, I was ambivalent before, and now I'm better-informed and still ambivalent. Thanks.. I think,

 

Pro tip again: any ear pad that fits the Audio Technica ATH-M50 will fit the PM-3. You don't even need to worry about the plastic mount as those pads can just go over the headphone instead. Though the plastic mount helps bring a bit more bass out.

I have glasses, and it is annoying, so I boosted the bass in my PM-3. And like Hands, I also have problems with the 3-7KHz range, so I took that one down. However, the peak at 8KHz persists and still gets in the way sometimes.

 

Upper mids sucked out? No way... The only problem to my ears is the upper treble.

 

Did you ever try the Meze 99s?

 

I had these and got rid of them after a period.. I desperately wanted to like and keep them, they did so many things right apart from one thing that I couldn't accept; a significant high frequency roll off (for me), if you listen to well produced music with high hats and other instruments on top, there'll be a lack of energy.
When I tested them at the shop I had my glasses on, and because of the small pad leak and bass decrease the lack of treble was more manageable so I bought them thinking they were fairly balanced, otherwise I found there was too much bass with proper seal. if they had + 4-5db in upper treble I would have been very happy - if there was a mod that could do something similar I'd be all over them like a rash

 

My experience as well, bass was a bit overpowering and too flat sounding for my taste, coming from dynamic drivers. I found I had to EQ about +5dB from 3 - 5kHz to compensate and add more energy to vocals.

I wouldn't call the Meze 99s portable. While it's capable of being driven easily from a phone, the fit is a lot looser so it doesn't isolate the best, and the headband doesn't fold down to make it easy to throw in a bag. The PM-3 folds flat, has a slim carrying case, is built like a tank, and has a 3.5mm input so it's easy to find aftermarket cables. That said, I found the Meze 99 matched my sonic preferences a lot better than the PM-3. I would have kept the PM-3 for the form factor alone if I had a decent solution for EQ from my phone.

 

Could you unscrew the driver an give us a look at it? I mean just 55mm capsule itself(there could be a possibility to mod the housing to bring more openness to the membrane)

 

The PM2 also was a fairly dull turd until I swapped out most of the black wool.
Similar driver means I would use a similar approach to dual density damping to boost /preserve upper range.
Bass should be monster with less damping if you like.

I was going to get one of these but went for Sine... A mistake as well.

 

Gawd I remember the PM2... it was the more lifeless boring, soul sucking headphone I'd ever heard. It sounded dark an neutral with EVERYTHING, every source, every amp EVERYTHING. I appreciated it's consitancy [like a refined beats] but hated it at the same time

That said, I have bill's MONSTER modded ES10, which is REALLY dark so I'm 100% comparing this Stock PM3 I got today, to his monster! I'm also looking forward to what he does to those pm3's! That Mad Wizard title is no joke, he's the real deal.

That said, first impressions of the PM 3 are positive for me. Don't find the bass over powering, don't find the high hats dead. They could have more energy sure, but I fancy this thing! I can see why SO many people recommend it. I'm curious to see how it sounds through other devices...