[Slater]

  Just for the sake of curiosity, how do you modders know what to mod? Is there a set rule to the process (like, doing A will have effect B), or do you go around plugging random holes and such and hope for the best?

Depends on if you're the pioneering type.
 
There aren't any set rules per se, but as you get more comfortable doing it, you'll find that many of the principles apply (and these same principles apply to full size and car audio as well). Stiffer cabinet materials, enclosure filling, dampening with absorption materials, port tuning, etc.
 
Personally, I do 1 of 3 things:
 
1. Wait for more experienced members whom I either trust or I know have similar sound signature tastes as me to develop/test out mod first. Many of these people are in the audio business and often have fancy testing equipment to validate the results of the mod testing.
2. If I get something that I am not happy with the sound signature, or it was cheap enough, then I try some mods to change the sound signature to something more to my liking.
3. Wait until multiple people have tried a mod and there is a general consensus as to the change.
 
Many mods are easy to try and only take seconds - taping off 1 or more ports, pad rolling, tip rolling, removing felt covers (which can be taped back if you don't like the change), quarter mods to foam pads, and changing to a better cable (on units with removable cables). And most full size headphones are only held together by a few screws, making them easy to try out a little fiberfill, or peel and stick on a layer of Dynamat or acoustic foam mat. Also, not all mods are acoustic - I always tweak the clamping force on full size headphones to make them more comfortable and increase the length of listening sessions. Often I adjust the amount of headband padding to correct weird pressure points and improve comfort.
 
I'm much less apt to perform more advanced/permanent mods - cutting holes in housings to make them open, swapping drivers, or adding resistors to increase impedance - unless there's a really good reason to or it's a result of #1 or #3 above.
 
The general argument is often 'omg everything is carefully designed by engineers and how can you know more than them?' Well, everything is designed with compromises - cost compromises, form over function (good looks but uncomfortable), model lineup compromises (we don't want model x to be too much competition with model y), material compromises (thin plastic or cheap crappy cables for example). And products are tuned to a particular sound or particular target audience, which may or not match my preference. So I can use mods to more closely match what I like. For example, I like an airy sound with big soundstage (who doesn't), but tight, warm, and powerful bass. But those features aren't always present together - open headphones generally lack bass, and closed headphones generally sound compressed and closed in. But even in those cases you can do things to tweak the sound to be more your liking.
 
There's no free lunch though - as you change one thing, you always change something else. Making changes to bass may affect mid range. Reducing sibilance may lose clarity and sparkle. You may get that monster bass but it may turn muddy. I've undone mods because I wasn't willing to accept the compromise of whatever it changed, so in those cases I may relegate that particular IEM/headphone to a particular musical genre or even movies or gaming only.
 
You'd also be shocked at the detuning manufacturers do because of product lineup compromises. A perfect example is the Sennheiser HD558 and HD598. It's literally the same headphone, same drivers and shells. The only difference is a few $0.50 strips of foam inside the housings, yet one is 50% higher in cost. Sennheiser can have more offerings at multiple price points, and lower models won't step on the toes of their higher model (and higher retail) siblings. Auto manufacturers are experts at this, and often the only thing between 2 marques at very different price points is $20 in badges - the rest is all marketing.

 

[vegetaleb]

   
That sounds kind of similar to the ATE. In stock form, they were designed to be fairly neutral, good soundstage, and light on the bass. They have to be modded to get them to really fill in the bottom end and shine. Modded, they remind me a lot of the port-modded Xiaomi Pro HD. The Pro HD are superior though, although the fitment of the ATE allows it to stay in for hours, where the Pro HD is always trying to work it's way loose in 1 of my ears (I think my left canal is smaller than my right). My plan is to encapsulate the Pro HD in custom molded thermoplastic to get it to stay put.
 
As far as the Starlines, that's one of the things they were designed for (as indicated by the text in this KZ photo):
 

 
Starlines have improved the bass (and comfort) on everything I've used them on, from the ATE to the ED9 to the Pro HD. I put them on everything that they'll fit on.

 
These starlines will make ZS3 bass less boomy?

 

[Slater]

 
These starlines will make ZS3 bass less boomy?

 
I don't remember on mine, but I could have sworn the Starlines CAME on the ZS3. So if the ZS3 is too bassy for you, I wouldn't ADD Starlines. I would try memory foam/Comply tips, which will knock down some of the bass.
 
The ZS3 is definitely one of the bassiest IEMs KZ makes though. So if you aren't a fan of their big sub bass, I'd consider the ATE or ATR. They have an airy sound, excellent soundstage, juicy midrange, and sparkly shimmering highs. Bass is tight, but waaay less boom compared to the ZS3.
 
HDS2 and HDS3 is also really smooth and refined.

 

[vegetaleb]

   
I don't remember on mine, but I could have sworn the Starlines CAME on the ZS3. So if the ZS3 is too bassy for you, I wouldn't ADD Starlines. I would try memory foam/Comply tips, which will knock down some of the bass.
 
The ZS3 is definitely one of the bassiest IEMs KZ makes though. So if you aren't a fan of their big sub bass, I'd consider the ATE or ATR. They have an airy sound, excellent soundstage, juicy midrange, and sparkly shimmering highs. Bass is tight, but waaay less boom compared to the ZS3.
 
HDS2 and HDS3 is also really smooth and refined.

 
I have the ATES because I wnated a memory wire, dunno why all memory wires models are bassy with KZ : ZS1,ZS2,ZS3 and ATES

 

[zabunny94]

These starlines will make ZS3 bass less boomy?

Try to get eartips with wide bore like kz whirlwind if you want a less boomier bass. That is like the rule of thumb of iem

 

[Slater]

Try to get eartips with wide bore like kz whirlwind if you want a less boomier bass. That is like the rule of thumb of iem

Good point. I was just coming back to add that to my post & you beat me to it LOL.

 

[Slater]

I have the ATES because I wnated a memory wire, dunno why all memory wires models are bassy with KZ : ZS1,ZS2,ZS3 and ATES

Interesting point. Their memory wire models are all pretty bassy (ZN1 was too).

The ATE-S is supposedly much bassier than the regular ATE (I just ordered some ATE-S for that exact reason).

Have you tried silicone wire guides? They are only a buck or 2, and can be added to any IEMs. Not the same as memory wires, but they do a great job for what they are.
 

 
One model you could also try is the W1 Pro. I am not home, so I can't verify that it has memory wires or not, but I seem to remember it does. It's also very light in the bass department, has a nice removable cable, and a custom IEM shell design like the ZS3/ZST.

Update: Ok, scratch that. I just searched and while it does have a memory wire, apparently they revised the model and the currently available W1 Pro is more bass heavy & less balanced than the original version.

At this point, the ED9 with the brass tube would be my recommendation.

 

[SomeTechNoob]

I don't remember on mine, but I could have sworn the Starlines CAME on the ZS3. So if the ZS3 is too bassy for you, I wouldn't ADD Starlines. I would try memory foam/Comply tips, which will knock down some of the bass.

The ZS3 is definitely one of the bassiest IEMs KZ makes though. So if you aren't a fan of their big sub bass, I'd consider the ATE or ATR. They have an airy sound, excellent soundstage, juicy midrange, and sparkly shimmering highs. Bass is tight, but waaay less boom compared to the ZS3.

HDS2 and HDS3 is also really smooth and refined.

I am 99.99% sure my ZS3s did not come with starline tips. Will go fetch the box, brb...

Nope, only the translucent gray ones similar to my ATRs and the gray ones with a red bore that come installed.

 

[Slater]

I am 99.99% sure my ZS3s did not come with starline tips. Will go fetch the box, brb...

Nope, only the translucent gray ones similar to my ATRs and the gray ones with a red bore that come installed.

 
Gotcha. No clue where I 1st got the Startlines then. The grey/red ones seem to be their goto model - they put it on just about everything. I have a box full of them!

 

[Slater]

So in the exploded photos of the EDSE, KZ shows the grille like it's wide open. But this is a flat out lie. The grille is for show only, and there's only a single pinhole-sized vent in the rear of the housing.



Well, what happens when we remove the 'fake' grille and turn it into the real deal? I've been wondering this since the 1st day I found out the grille was just for show (the grille easily lifts off with tweezers or an xacto knife). I had no idea what it would sound like once opened, or even what was directly behind the metal back since it's all closed off and you can't see the layout inside. All I had to go by was the exploded diagram, but it didn't show any of the wiring. I was honestly assuming I'd destroy the thing by driving a drill bit right into the driver or wiring. Or that it would sound like crap and there was some reason why it was sealed up despite the diagrams showing it wide open. Although if I didn't like how it sounded opened up, I could always just seal it back up with a metal/wood disc to put it back the way it was.

Well not only was I surprised by how well it worked, but I was even more surprised by how it sounded.

Here's what I ended up with:



If you do this mod, be very careful and go very slow. The back of the EDSE is crazy thick - like 3mm, and takes a while to grind out. The aluminum gets hot, so you have to keep taking breaks to let things cool down. I alternated to the other side while the side I just ground on was cooling down (so grind the left, stop when hot and grind the right side while the left cools, then repeat until you're done). I used small drill bits on a Dremel (no way would I use a drill), and kept stepping up to larger drill bits. Then I switched to carbide grinding burrs. The key is to just drill & cut through the metal and stop before hitting the wires coming up and out of the strain relief. There's 2.5-3mm of space between when you pierce through the metal and when you hit the wires. So when you detect that you have almost pierced through the metal, you have to ease off on the pressure so when you punch through you can pull back out to prevent hitting the wires.

Once I was done, I blew all of the little bits of aluminum dust out with my mouth, but you can also use a can of compressed air.

Leave a little edge so the stock mesh has something to sit on. The stock mesh is held on by an adhesive, but it's pretty weak and was kind of dried up, so I just used a few specks of epoxy on the edge around the grille (applied with a toothpick), let it dry, and it's good to go.

Here's what I've noticed:

1. In the stock EDSE, the midrange sometimes comes across as slightly thin and compressed. With the mod, the mids sound rich and full. The compressed feel is gone, with the difference sounding like changing the Stereo Width (in Rockbox or similar) from 100% to 125%. Midrange sounds more 'complete' and thicker if that makes any sense.

2. The mids are recessed in the stock version, and the modded version makes them much less recessed.

3. Separation is improved. With the stock version, male vocals were often bleeding with drums, which was very distracting. That is really improved now, with clearer separation where it was bleeding together before.

4. There was decent bass in the stock EDSE, but bass sounds better in the modded version, both quantity and quality. Kick drums sound like your head is 2 feet away - you can feel the vibration, where you didn't get that same feeling before. It's not boomy, but clean and punchy.

5. Soundstage is improved slightly with the mod.

EDM sounds amazing - the music feels like it's being played directly in your head. I've always liked the ED-based models - good sound, comfortable fit, effortless insertion, and quality construction.

The stock EDSE is no slouch, and is a very good representation of a "typical" KZ v-shaped IEM. However, modded it sounds cleaner, crisper, and just plain more fun overall. All and all, a very worthwhile mod to such an inexpensive IEM.

 

[Mus1c]

Although im more of neutral sound guy SO far the ATR sound bassless to me. Maybe some BI time and they will shine the separation is fantastic though. I did not get the cable. I might later on if M noise annoys me. I wonder if the starline tips will fill in the bass? I have the ED9 that i got last week. The bright tips i wonder if the starline can fill in the bass? Ill try the ZST later to see the hype.

yeah give some bi time to really shine the sound, at first it sound bassless but in end it will shine and give that nice tight rumble bass.

 

[Mus1c]

Can anyone compare the ZS3 with Xiaomi hybrid Pro or Pro HD?
I have the ZS3 but find them a bit too bassy, would the xiaomi iem give me less bass and better mids/soundstage?

i dont have hd pro but zst is right choice for you if want that massive sound stage, less bass,better mids and treble.

 

[Mus1c]

I have the ATES because I wnated a memory wire, dunno why all memory wires models are bassy with KZ : ZS1,ZS2,ZS3 and ATES

you can use this as a option to full fill your need.

 

[vegetaleb]

you can use this as a option to full fill your need.

 
Yeah I tried them on my HTC 10 HiRes bundled earphones but the cable keep going out and it won't give the tight fit of a memory wires, though I have found that even the ZS3's memory wire can be irritable after 3 hours of ski.
I will have to give these ear guides a second chance

 

[Slater]

   
Yeah I tried them on my HTC 10 HiRes bundled earphones but the cable keep going out and it won't give the tight fit of a memory wires, though I have found that even the ZS3's memory wire can be irritable after 3 hours of ski.
I will have to give these ear guides a second chance

 
You can carefully remove the memory wires (if they're too uncomfortable) on most any KZ IEM. It's just a thin bendy wire inside some heat shrunk tubing. Just gotta be careful you don't cut into the main headphone wires.
 
I found what is more comfortable than the memory wires are the little weights, like KZ used on the original ATE (not ATE-S):
 

 
They aren't as effective as memory wires, but they still work well & can be worn for hours with none of the comfort issues that come with memory wires.
 
I wish they used it on more models instead of the memory wires. Or that there was a way to add them to existing IEMs without requiring that the wires be removed. It wouldn't be hard to design something that snaps together like a ferrite bead: