You get what you see. Nothing extra.

CNT or “Carbon nano tube” diaphrams/drivers were developed by the Chinese (I studied this) and J.V.C was the first to mass produce it in their IEM “FX” Series.

Essentially a 55mm driver dedicated to low frequency . They actually called it a “Subwoofer” (a 30mm driver handles mids and highs)

Full tech explanation here>>>>>>HA-SZ2000   JVC

It’s a Double Bass reflex design using the “Kelton Method”

Does this scream audiophile to you so far? It screamed Basshead to me.

Kinda screams this…

Old school 6×9’s…….Oh nostalgia. Before dedicated subwoofers were the norm this is how they got low and highs  (Car audio hi-fi ladies and gents) together…they “stacked” em.
Cars allow the space and freedom to divide and conquer the signal drivers but headphones……not much room.
JVC gets a lot of points for their creativity. This SZ series died a quick death due to many reasons.

1 Maybe the greatest Low frequency response headphone ever mass marketed and produced…….never aimed at the market most likely to eat it up
2 Outside design looks Hi-Fi while the sound signature is not.
3.Limited release and lack of follow up adjustments.
4…sadly the guy that was the genius behind this may be working in SIberia as it was an epic FAIL.

I give this 5 stars because it’s bass is unmatched. The impact is superior to a line named Xtreme Xplode (Noooooooow they aimed at the crowd)….with the 2nd best design.
It responds to eq adjusting unlike any headphone I have held. The response line is a rubber band that will do about anything.

The BASS…might make you sick. Previous owners might be able to comment on this. If you boost the already dominant bass it can cause a kind of nausea. I saw friends in my car audio days vomit after to long a ride with 2 15″ subs slamming into the cars frame.

If someone blows into a large bottle a moment of resonance occurs and you feel it. It’s uncomfortable. While your bass is pounding your head a subsonic tone is coming through those 2 tubes and though you cant hear it it is filling your ears and body. It might be in my mind but I don’t think so. These cans bass might make you feel ill

I will update this later.

This is an import series that is apparently discontinued. I would recommend any bassaholic chasing the next big hit to get these before they are no more or go up in price because a niche’ market of Bass oriented audiophiles take a shine to it and drive the price up.

Bass volume (exceeds amplification max of a FiiO e12) 1st time experience. That is by far ..nothing did that before and it has a 16 ohm impedance?
Bass Depth (rated down to 4Hz….the first time I never questioned a claim of production beyond the audible range because you can feel it)
Bass Texture (It will do whatever you want it to do from the low end side…it’s ‘texture” is so smooth it slips down your throat and makes you sick…that sensation anyway)

I will update this review after a while of usage. It has only played with Hip-Hop music.

Used for extension at high volume:

Used for Bass hit impact:

Used for Bass response (speed)

EDIT: 3/21/14

I ended up changing the pads on these.

This took 2 minutes and changed the mids and highs a lot. Not sure why JVC went with the smaller padding but it was a terrible oversight.
Bass impact was not altered by the pad change. These came off the 55x of JVC’s XX series so I didn’t expect bass impact would be diminished. It feels tighter.
These are the hardest bass cans I have ever heard. The Honeymoon fanboy period is over. These are just awesome.

 

Original Post from Extreme Basshead club on Head-Fi Below

 

 

 

 

1.  This is not a review it’s an argument for calling this set of cans the hardest hitting on the consumer market. That claim needs data. Others need to be able to confirm and compare their cans.  Give me some time.
2. Everything is based on changing the original pads to a firmer pleather

 

Making the case

Everything in the robust sub-bass region is related to a “Kelton Subwoofer”.

 

Exploded view
(The second panel from front shows the cover under the pads. It’s twisted to 2:30 instead of 6:00 where the bass ports come out
Who the **** does that? This is JVC in a visual. You go all out to make something special and **** 1 little thing up. That’s JVC in a nutshell. Every layer is tech awesome and you throw some shallow pads on the top…..tha fuu??)

55mm Carbon “Sub-woofer” and 30mm cnt (Carbon nanotube )

SZ1000 (L)   SZ2000 (R)  <<Uses brass housing for strength and to deter resonating

---

 

Low Frequency Harmonic Distortion Sound Test

Driver check.
Drivers responding clearly at low gain to human hearing thresh hold (18-20Hz)

SUB-BASS

(20-60Hz)

1. 20Hz
2. 30Hz
3. 40Hz
4. 50Hz
5. 60Hz

 

MID-BASS

(65-120Hz)

1. 65Hz
2. 75Hz
3. 85Hz
4. 95Hz
5. 100Hz
6. 110Hz
7. 120Hz

 

UPPER-BASS

(125-250Hz)

1. 125Hz
2. 150Hz
3. 175Hz
4. 200Hz
5. 220Hz
6. 250Hz

Mp3Skull Bass test tracks

250-2k (Mids)

2k-16k (Highs)

---

Testing

 

1. Testing will be done using music tracks. (Hip Hop).
2. There will be NO basstronica, Trance,Instrumental/synth-centric tracks.
3. Sine-sweeps and tone loops are only used to confirm driver response thresh-hold.
4. The “Cool Story Bro” crew will be put to sleep with video demo’s. They are invited to try and replicate demo’s with their own cans.

 

Testing Equipment 

1. Cowon iAudio 10
2. FiiO e12 Mont Blanc
3. JVC-HA-SZ2000

Regular mid-level goods. Total cost $500-600 (Cans+Amp+DAP)

Preview of visual aides

 Lvl 1 test

(Shows energy being transferred by driver to cage)

Not common but not rare. Any 50mm+ driver with low,mid,high end bass should be able to do this. Some 40mm possibly as well.
This test can be gamed and the paper size and material can greatly effect the visual display of energy.

Lvl 2 test

(Shows energy being transferred up through ear padding and air pressure change within area between driver and ear)

This is very un-common.  That paper is  analogues to human skin and the energy being felt by it. It’s not a perfect analogue but the point is made fairly well.
The final video will be an unedited one showing exact settings prior to display. As this it will be a Cowon at 34 volume with a flat 5 band eq mach3bass at 10 and BBE at 8. Fiio e12 amo with bass boost on, gain on and volume knob at approx 50% (all will be clearly seen in final video).

Anyone who has bought a pair of bass cans because they were told their “face will melt”, “eyeballs will shake” or any # of wild claims only to get the cans… put them on and be absolutely underwhelmed in the face melting, eye ball shaking dept……will appreciate the effort I put into SHOWING what it does v.s. saying what it does.
This display is not near distortion levels. I like my cans. I do not need to damage them for entertainment. The work they do under elevated but not insane levels is clear enough/beyond most if not all.

---

This section is reserved for a video of cans that display equal to or exceeding energy
transfer through the pads. Lower padding held down by opposing cup or object. 3 sides
left unimpeded. Using this track 3:40-4:02 to be exact. Anytime. PM me.

 

---

 

Test Tracks

Why this track?

Because it is like a Hip Hop producer channeled  Phil Spector’s “Wall of Sound”.
It is waves of layered bass hits underpinned with a sub-bass stroke that will keep the driver busy at all times.
This track shines on the sz in a way that puts other heavyweights to shame. It articulates and reproduces all of the mastered track with authority. If you listen and you think..”meh…just another hip hop track” you’re not listening loud enough or your cans just won’t bloom under the crushing pressures this track puts on the driver diaphragm.
100 million You-tube hits and I’ll bet a good portion are pure breed bassheads.

Why this track?

Because it is the classic bass hit. An atomic blast dressed up like a proper bass hit. It’s also nostalgia for me. This hit destroyed/exposed your favorite can.
If you do “A” “B” comparatives between cans while they’re together (only way it should be done) then this will make one stand out. The Yamaha 500 and Ultrasone 900 do this hit well because it is good at mid/upper bass showcasing but the sz still takes this slice of cake. What is a safe listening level? Is this too much? This track at high gain will make you ponder such deep questions.

Why this track?

Because it is a high gain track. It pulls mids and highs and ties them to the bass smoothly if bass is raised by +15dB. It is new. Well mastered and displays a punchy hit usually reserved for a slightly higher Hz but places it lower. (Maybe aimed at Car Audio heads) One of my newest fav’s

Why this track?

Because this is a track that seems to have 2 layers of low end bass response however it has 3 clearly. The 3rd is only heard at very high low end gain. It sounds like a different song on these cans. Without mentioning cans I’ll say my 2nd favorite start to echo while these rigid housed drivers keep it together. This is similar to the Wiz track in that you are always being hammered and sometimes with multiple magnificently mastered low end spikes. While the Wiz is pinned with a low tone this is hung with higher hits while low 20-35Hz punch you in between. It’s like an inverted Wiz track.

---

 

Science n’ stuff

 

This is where the 77’s end…along with the Pro 900 and ANY other 40mm driver and most 50+ with plastic housing. Just before both the 57mm JVC and the 40mm titanium Ultrasone physically distort they start a resonance/echo chamber acoustic downfall…and then immediately begin distorting

<<<Your ear is here.
Sound waves are longitudinal waves (Red line is your driver)

The SZ is using chambers to force high freq sounds out by filtering them naturally since high frequency
waves reflect easier than low frequency waves.Low are longer and wider. They deemed the 55mm driver a “Sub-woofer”. It is essentially working in that fashion. Having a driver dedicated and forced to fight through chambers is assuring a powerful low frequency response since the driver is technically only being tasked with that duty. Mastering these headphones to get the two drivers to cooperate is the user end challenge. For Hip-Hop (to this user) these are perfect. They are the ultimate “Basshead” cans though most bassheads have never heard of them. They do not look the part and were not even marketed in that way.

Quote:

For f__ks sake…Embrace the bass.

So they built a Sub-woofer based set to be played loud but it’s not for bass enjoyment????

O.K., Sure.

That’s why folks got 40mm single driver celebrity endorsed basscans on their heads which will crumble and distort long before the ones you guys spent ages to build because you couldn’t embrace the bass? How about…mmmm..I dunno….market them just a little to the tween-er crowd that uses moms money or what they saved at McDonald’s working part time to buy the baddest ass headphone bass monsters on the planet. Now you got folks rec’ing (insert ****ty can here) because they don’t even know what the **** you built. Accidental Einsteins …awesome

The thing…I was trying to tell/yell at folks for 2 months was what was the big deal. These really do shake your eyeballs. They vibrate the upper neck as well.
After having these for 3 months it’s clear to see,the way a bass can delivers the sensations beyond the pads is related to the human skull. The rear of the pad vibes but your skull…it’s thick. The area in front of the pads like your cheeks and the short jump to your orbital area and your meat filled neck……if you tune these right and have solid pads you are going to be very impressed. It is a unique experience

---

 

Analysis

Above is an SMS DJ PRO which…

Below is the sz

Can shaking hit on Kendrick Lamar’s MAad City (above)

Massive bass bomb from Rah

SMS

SZ

**This was on a reduced gain because the SMS could not reproduce this hit without distorting/crackling unless I lowered the gain. That lowered gain is the same for the sz snapshot. It’s an apples to apples comparison.

I’ll revisit this hit later to see what the sz can do before it’s own limit is reached.

---

Deficiency Notes

Denon has an entire industry built around it’s cans and the improvement of them. Take a diamond…shine it up…I get it.

Many great headphones have deficiencies that are adapted to and overcome by loyal owners who see the profit in further investment. This is great…I wanna make it greater kinda thing.

The SZ2000 must have a pad change. End of discussion.
You wanna hear the mids and listen to Jazz? Get some Beyer pads/HM5’s
You wanna vibrate your neck? Get a pair of JVC 55XX grab the pads and toss the rest in a river and tell yourself it’s an offering to the bass gods and never look back.
Sometimes you gotta do ****. Suck it up and go the extra step.

---

Pre-conclusion conclusions

1. The Carbon diaphragm is allowing for a stronger low frequency response. It has characteristics that caused JVC to use it for their “sub-woofer”.
2. That brass
3. Hardened ass end reflecting almost all energy forward via direction (bass tubes) or reflection (metal driver housing)

---

DEAR LORD

Yup.
Ya missed the entire thread devoted to the cans.

While I wasn’t looking these cans became highly controversial..
Sub-bass cannons with vids on vids showing it not saying it…and it’s contro……….like I said “DEAR LOOOOORD”!!!

---

Great write up by a Non Hip hop head

***to be continued (The Case for Bass is approx 60% complete as of 7/12/14)