JVC FX33 Mod.

[RokabillySwagger]

I just did my brother's Mallows too. He liked the fact that the highs are more apparent and the overwhelming bass is a bit less overwhelming. Nice little mod i must say.

[cmirza]

With some free time today I tried this mod and was a bit disappointed. While it did open the highs as promised, I just find the highs to now be scratchy and unrefined. They aren't as enjoyable as they used to be. I'll just give them away to a friend. Oh well. I guess this mod isn't for everyone.

[MusicallySilent]

I might try this with my marshmallows and hope I like them... otherwise I will probably just get a nicer pair of IEMS (er6i superfi3 shure e2 with mod etc.)

Maybe this will be a cure for bassheadism

[mwallace573]

I grabbed a pair of these last Thursday to help ease the pain of me waiting for my Livewires to return. Needless to say I never gave them a chance stock. I performed the Kramer mod upon arrival. I must say I'm quite pleased with them, especially for $15. I was planning to return them once my Livewires got back, but I may end up keeping them as a backup should the unthinkable happen.

I didn't have a KSC75 pad handy, so I ended up using the foam off the end of a microphone that was attached to a defective headset laying around at my work.

They're no KSC75, but if you need isolation and only have $20, then you could do far worse than to pick up a pair of these. Thanks for another great mod Kramer.

[derevaun]

I felt pretty much like cmirza after removing the paper baffle. I've eventually discovered the right amount of foam to stuff in the post to get them back into balance, which I can't really say is a lot better than the original state, because I can't remember that well I don't recommend listening to them between removing the paper baffle and putting some foam in place. FWIW nobody has recommended that.

But it's worth noting that removing the paper baffle is a commitment to tune the Marshmallows until the sound is satisfactory. I like to tinker, so the journey was enjoyable enough to make that part of the mod worth it. A big thanks to the OP!

[jigabachi]

I wasn't looking for a pair of new phones but heck, I found the Marshmallows at the local mall for just $20. I've only been familiar with the Sony-type silicone tips and was curious about the JVC's foam tips, so I decided to grab a pair.

Sound-wise, I think everyone knows how decent they are for the price. The mod works for me and it does help to open up the sound a little. While my canals felt a little more stuffed compared to the Sony tips, it wasn't uncomfortable. The seal is not as isolated and I find the phones to be perfect for outdoors jogging, especially when connected to my SE phone.

All in all, an excellent mod for a pair of very decent casual-listening phones.

Edit: BTW, I did not use pliers to pull off the glued-down gray tubes... I just used a flat-tip jeweller's screwdriver to reach into the tube and scrape off the paper cover. Less chance of damage, IMO.

[Prozakk]

Originally Posted by kramer5150

I thought I'd start a dedicated thread, I posted this on that other thread-monster and it wasn't getting the visibility on page ~30.

Here you go!! Compared to a stock phone, this mod makes them brighter and increases upper mids and treble, so its no longer overwhelmed by the bass. If you already find the FX33 too bright or harsh, you may not like this mod. If you find the FX33 muddy, bass-bloated or congested this might be a mod for you. Readers should also note that this mod is not-reversible.

First you have to pull off the foam tips. Just gently pull them off with your fingers. They slide off with a little tugging. Once the foam tips are off, grasp the gray rubber tube with some pliers and pull them off. They should pop right off with a swift tug. There is a little glue that holds the rubber tube in place. I think other members have used different methods to remove the gray tube. Please feel free to post other methods!!

Use a sharp x-acto knife and cut / scrape off the paper filter screen. You can see in this pic there is a perforated metal mesh screen protecting the driver. So the driver is still relatively protected without the paper.


So... thats half of the mod. Give it a try. At this point, slide the gray rubber tube back on, and slip the foam ear-piece back over it and give a listen. It should be a LOT brighter than before. I found the brightness harsh and piercing. So... its on to phase 2.

Next take an old earpad foam from a junk-can and cut a small cube shaped piece out of it. Roll it up and insert it into the sound tube. The foam helps to attenuate the highs, and keeps earwax out of the sound tube. You can experiment with different sizes of foam. With larger foam pieces, the foam is compressed more dense into the tube, and more highs will attenuate. It is a trial and error kind of thing. I ended up cutting 3 different sizes of foam and using one that was just a little larger than the inside diameter of the plastic sound tube.




Heres the little foam filter piece. I used an x-acto knife and sliced up a KSC75 earpad cushion. Just cut a little cube, scrunch/roll it up and shove it in the tube. You don't need to cut it into a cylinder shape.


Once the foam piece is securely snug inside the tube, slide the gray tube back over the sound tube and pull the slieve back onto the tube.

Its a pretty night and day difference IMHO. I was comparing them to my nieces unmodded FX33 and the difference was very noticeable, even for her (a non-audiophile). I told her to keep whichever phone she liked best. She chose the black one, more for its looks. Of course you can combine this with any of the tip-mods. I find the stock tips the most comfortable, so I just leave them alone.

Good Luck!! and happy modding.

No step-by-step pics? Bummer.

[ChickenGod]

Originally Posted by Prozakk

No step-by-step pics? Bummer.

If you actually take your time to read it. They basically are step by step pictures. The steps are so simple. Just read it and it'll help a lot.

[Prozakk]

It will probably click more if I have had some descent sleep this week. Exhausted.

[nameles]

I bought a pair earier this week and found the sound to be harsh with little bass. In fact it was so harsh that I now have a buzzing in my head that I can't seem to shake and I don't think I played them all that loud. Poeple here seem to be experiencing the opposite... too much bass, weak highs, which this mod is intended to correct. I assume this mod is not for me. Is there any way to increase the bass and soften the harshness of the highs? I did notice that it seems to have improved a bit over time. Do these benefit from burn-in?

[TURBO]

I would like to say thanks to Kramer. Why, because there is one less thing that can go inside my ears. In mine the little paper filter was kind of loose. It was very easy to take it off, so that filter could be a risk to stay inside my ears. Thanks Kramer for discovering this mod. Besides this mod, I added a 75 ohms impedance adapter and my marshmallows sound marvelous and very fun. Of course with the marshmallow's sound signature.

[Joshatdot]

Originally Posted by nameles

I bought a pair earier this week and found the sound to be harsh with little bass. In fact it was so harsh that I now have a buzzing in my head that I can't seem to shake and I don't think I played them all that loud. Poeple here seem to be experiencing the opposite... too much bass, weak highs, which this mod is intended to correct. I assume this mod is not for me. Is there any way to increase the bass and soften the harshness of the highs? I did notice that it seems to have improved a bit over time. Do these benefit from burn-in?

Get Shure E2 Orange Foamie tips...or anything that makes a better seal to your ear.

[kevg73]

i just did this mod today on a pair of sony fontopias. i like how my marshmallows sound so im leaving them. but the paper filters on my fontopia got so dirty that it hurt the sound. i did this mod and theyu sound much better now. im pretty sure this mod will work on basically any IEM's that use the same basic design of a paper filter and a stronger guard directly over the cone. so for me it was basically just a filter replacement.

btw if you find the highs to scratchy and rough just add more foam and it softens them up a bit. i basically did almost as much foam as i could fit in the tube

[Austin 3:16]

I modded mine. Removed paper filter. Added rolled piece of cheap 'phone cover foam. E2C Olive foam tips. Next, Dynamat the exterior to dampen enclosure resonance.

[Chickenman]

Got mine for 12 bucks at Amazon. Reading the posts, does more foam = less harshness in the highs?