Sony MH755

Summary:

The MH750/755 variants having such a long history have also been investigated by other hardworking mates. I'm deeply appreciative of their advice and humbly give thanks to them too..and many others not named with apologies, those who I would greatly mention are @crinacle @Slater @TheVortex @axhng @eqsOne @Nuclear Reactor @ClieOS @mochill @aspire5550 and finally @Sead (Member of the Trade: Sony Mobile)

Just again to highlight.. Sony's OEM ( They designed, engineered, and make the prototypes but contract out to others for mass mfg) has 2 iterations of their drivers (pop it open yourself, only takes less than 2 mins with a thick pin ) from 2012-2013/4 (13WK-XX) -Off-centered oval vent & their newer 2015/6/7/8/9 (15WK XX onwards) with centered round vent and they do share almost identical sound signatures except the newer versions has a slightly elevated Mid/Sub Bass,

This was also agreed upon and mentioned by @TheVortex & @aspire5550 https://www.head-fi.org/threads/chinese-asian-brand-iem-info-thread.820747/post-14705306, as I believe Sony had to work with that, due to different factory contracts, product improvements and cost reductions thru the years, but are very strict on their preferred sound signatures to be as close to their prototype as possible.

How to Find/Buy a unit Today :
(They are getting very rare due to the lack of mass production )

Xperia Phones are Bundled with the MH750 , TYPE: AG-0500/AG-0501 (Black/White) , not MH755 (Shorter cable without microphone)

It's practically impossible now to get the older off-center air vent MH755/750 TYPE: AG-050X version made in 2012/13/14 anymore usually with MFG dates 13WKXX - 2013 Week XX. & 14WKXX - 2014 Week XX

MH750/MH755, TYPE: AG-0500/0501/0502/0506 , Mfg 2015-2019 (Center air vent) , can still be purchased from limited sellers, of course, may also be bought together with the Sony Bluetooth Receiver and recently also spotted the 2019 standalone MH750 Sony retail package


There are also reports of the newer MH755 retail packed with Bluetooth with a Straight 3.5 mm jack instead of a L-Jack and discontinued usage of the CE tagging with Product details on the cable for MFG 2017-2019

Did an in-depth 3 different Types and spent 1-week doing A/B/C testing so you don't have to :

1. MH755 AG-503 - MFG 2013 13WK27 - 2013 Week 27
2. MH750 AG-501 - MFG 2017 17WK42 - 2017 Week 42
3. MH750 AG-500 - MFG 2015 15WK52 - 2015 Week 52

Sony has another new variant mfg in 2019/20, with the straight 3.5mm Jack but since I don't own it or able to buy it ..I'm sorry I will not be able to comment on the sound signatures.


Below an image of the MH750 bundled with the Sony Xperia XZ2 Phone MFG 2017, notice it no longer has any CE markings or labels on the cable


The side vent that started all the confusion on the Internet with the MH755 VS MH750:
TYPE: AG-0503-MH755 (Mfg:2013) AG-0500/1-MH750 (Mfg:2014)

The 1 to 1, 100% Identical off-centered air vent MFG 2013-MH755 & MFG 2014-MH750 whereby the MH750 is super rare as you can't just buy them from any online stores as they are bundled only with Xperia Phones thus why @crinacle made an incorrect assessment in 2019 review and comparison of MH755 (MFG 2013, Side Vent) vs MH750 (MFG 2017, Centre Vent) as they are 2 different hardware variants from different manufacturing periods back then.


The centered air vent, MH 750/755 has various TYPE: AG-050X versions.


This is how a fake MH750/755 driver looks like, without the 2 small eyelets, also most likely not secured or glued to the shell, thus in some cases, users have complained of a loose driver when the shells are shaken.


Lord of The Vents ;

In relation to 2013/14 side vent and the later & current common center air vent drivers
In my earliest memory, the MH750 model appeared first before the MH755, via the Ericsson-Sony partnership in 2011/12.


And it shouldn't be a surprise as all Sony Corp Comparison Charts use MH750 naming and not MH755 as to Sony they are one and the same product when it came to comparing with other earphones.


Why the air venting system tech, pray tell? Well due to the small form factor of the MH series from Sony, the vent assist in their microstructures and offers superb bass performances and maintaining detailed clarity with the treble,

Thus why there are always 2 x solder dots to secure the driver/shell from vibrations in Sony IEM, dated as far from the beginning (see Image below of Sony Ericsson W800,MH700, etc IEMs), another awesome example is the microscopic MH1 IEM.

This tech alone shows why Sony is legendary and groundbreaking in audio fidelity even today!


A Myth-Busting Recap :

1. MH750/755 shares the same drivers
2. Only differences are the thin short or longer thicker cable with Mic variants
3. 2 different H/W variants verified through the years

2013/14 - Side Vent Drivers
2015-2020 - Newer Centre Vent Drivers

Both versions can be identified as genuine with Sony's trademarked 2 x Solder Dots

An Extremely rare side vent MH750 mfg 2014 taken from a Sony Xperia Z3-- Yes Side Vent Drivers are not exclusive to only the short cabled MH755..as Sony uses the same exact drivers with the MH750 too

Finale:

Good Luck to Everyone Now go find this hidden Gem Fast as its getting Rarer (Side Vent MH750/755 ) as we speak

Edit/ IMHO I actually prefer the newer centre vent variants MFG in 2015-2019 versions, due to its all-rounded MID/SUB Bass and less peaky treble signatures.

You can't go wrong with this IEM. Nothing better can be found at this price. And even in the $ 100 price range, it will be hard to find a better IEM. The sound is clear and balanced, the bass is deep and clean. The highs come brilliant. The mids are comfortable.

Check out more reviews at: https://www.perrivanaudio.com/

Setup and price: 1 Dynamic Driver (17 SGD with shipping)

Intro

Disclaimer: This review was done by my own accord and I purchased this set at full price from eBay from KANOYA Japan.

The MH755 houses 1 Dynamic Driver and I bought it at about 12 USD (including shipping etc) at the time of my purchase, however its pricing may vary depending on sellers since Sony does not sell it on its own. It is also important to note that there are many fakes out there so do check out for its authenticity before any purchases are made.

Before we dive into build and sound, It is almost a must to do a MMCX modification to it since attached cable is so short which makes it very impractical in my opinion. It costs about SGD 25 to modify it nowadays or you can look up some videos online and do it yourself if you are savvy enough.






My personal unit modified by SG AudioHive (ear tips: Final Audio Ear Tips size M)

Packaging and Accessories (Score: 3/10)

Nothing much to say here since it was an accessory itself, it comes in a plastic package containing the earpiece and tips. However I would like to point out that the stock tips are really good in terms of fit and quality so huge plus for the price you are paying!

Build and Fit (Score: 5/10)

The build here is typical for something like this (the free earpiece that comes with your phone) it is all plastic and not durable so really nothing great here since most of the value comes from its sonic characteristics and performance.
Fit wise, I usually wear it hanging down (unlike over ears) so it really depends on the tips to give you that seal and since given its design, lower your expectations when it comes to seal and fit (stock form) unless you tip roll to something that suits your ear. But I do have to say, it is relatively more comfortable to wear it for long hours as my ears get tired and discomfort from wearing IEMs for too long.

Sound

This is where it really shines for this unit, it poses a “Harman-Neutral” sound, good sub-bass extension with a peak in its upper-Mids which some may describe it as V or U shaped (in this case I would classify it as a U-shaped sound signature). The MH755 is fun to listen to, has good timbre and tonal balance for its price and is often described as a “wonder” for many.





Taken from Crinacle.com/graphs

Sources used: (Topping D10 > Atom Amp) and (Ibasso DX120)

Bass (Score: 8/10)

I really love the sub-bass that MH755 has, it creates that rumble that can really satisfy my sonic cravings and it just became my go-to when it comes to songs with low bass. Mid-bass on the MH755 is relatively less emphasized as compared to sub-bass but it is not lacking or missing, “thumps” are still clean, fast, and textured or in other words, “the dynamic driver kind of bass”. In overall the bass here is boosted but not too much such that it overpowers other frequencies with minimal mid bass bleed.

To elaborate on its bass performance, I would say that I can single out the bass lines clearly despite having other frequencies playing at the same time (including vocals) but does not get in the way of clarity or sounding “muddy” which is something that I really like about it. Quality and quantity bass without losing clarity and tonal balance.

Mids (Score: 7/10)

Mids on MH755 is decent, vocals are clear but slightly recessed or less emphasized. Male vocals tend to sound fuller and deep due to the tuning of bass regions. Female vocals are generally clear however there is a peak around upper midrange (rising from 1khz and peaks around 3khz) which may sound slightly harsh on some songs but generally acceptable for me.

In general, the mids on MH755 are decent, not lacking and they are good enough for me to use it as a point of comparison for anything below SGD 100 which pretty much shows how well-tuned this unit is.

Treble (Score: 7.5/10)

The highs on MH755 are energetic and adds a little sparkle and air to the overall presentation but also at the same time smooth in my opinion (It is not sibilant to me as my sensitive regions ranges from about 7khz to 10khz which in this case is being rolled off from 7khz onward and treble addicts may feel a bit underwhelming.

Sound stage, Imaging and Tonality

Sound stage is pretty decent on this, I was able to feel that space that they recorded those tracks in and I would say it is pretty decent. Imaging on the other hand sounds a bit blurred even in binaural recordings.

An important point for this unit to perform is to achieve that seal and normally, IEM that are 3D printed or have “custom-like” shells can achieve that easily as long as the shell fits your ear properly. However, for the MH755, it is worn hanging down and the TIPS makes the world of difference here as it really diminishes its bass capabilities if you do not get a proper seal. It really depends on the tips that fit your ear but I am currently using slightly larger tips (Final ear tips size M or L) to achieve that seal.

Overall (Score: 8.5/10)

Value is key here because even though modifications are needed, the sonic performance of the MH755 at this price point is just unbeatable. There are other cheap modifications available such as a 3.5mm extension cable (it works but not pretty but it’s the cheapest) which you can explore if you don’t mind the looks. Also build wise it’s below average at best as compared to modern day offerings but for that level of sound, I do not mind buying multiple units just in case if mine starts failing.

Conclusion

I must admit that I was skeptical about the hype for MH755 and thought that it was just of the usual hype trains that people get excited about and then dies off when new products flush the old ones away, but I was obviously wrong. In fact, this might be one of the greatest sucker punches that Sony can pull in the entire audio industry. The MH755 is hard to fault with no obvious flaws or flags that I can think of at this price point and I recommend getting one before it disappears from the world in the future.