RHA MA750 Part.2: General analysis

Continued from Part.1, Aesthetics

According to RHA's website, they intend to "deliver the most accurate, comfortable and unobtrusive listening experience possible" to the users. And their proprietary Aerophonic™ Design along with hand-crafted drivers indeed represent such commitment.

RHA's description on their Aerophonic™ Design

In short, Aerophonic™ Design utilizes end-correction effect of a reverse-horn, and effectively attenuates the high frequency range. Consequently, an accurate frequency response shaping is possible once the horn is combined with a proper design.

The official frequency response of MA750

And surprisingly, the manufacturer voluntarily disclose frequency response charts of their products, just like Audeze and Etymotic Research, all of whom known for great sound quality. As it usually means they are well-aware of what they are doing, RHA must be very confident of MA750's sound.

PRO: High frequency extension up to 20 kHz & low distortion.

CON: There's a good amount of channel matching issue below 2 kHz, along with a slightly recessed mid-range.

ON SECOND THOUGHT #1: Insertion depth-wise, an intermediate depth probably works best for this particular IEM, as can be seen above.

ON SECOND THOUGHT #2: A sheet of microfiber cloth should help tame the peak at 5 kHz; However, be advised that such modification may push the mid-range even further away than already is.

ON SECOND THOUGHT #3: To whomever bloated bass is of a concern: Blocking the vent located on the top of the housing should resolve the said problem somewhat.

ON SECOND THOUGHT #4: In order to suppress the peak at 5 kHz, bore resonance must be adjusted. So here's my recommendation: A pair of large Meelec triflange ear sleeves should shift the resonance, and even out the high-mid range anomalies. And once it is combined with a pinhole vent mod, the sound of MA750 becomes a lot more balanced and enjoyable.

ON SECOND THOUGHT #5: The purple curve is my occluded ear simulator measurement(raw at the reference plane), while the orange is of RHA. For some reason, RHA's official frequency response chart does not match any of my data. Perhaps it is because they use a 2cc coupler for measurement?

ON SECOND THOUGHT #6: RHA MA750 doesn't quite meet Harman International's reference target for headphones.

ADDITIONAL INFORMATION:
Manufacturer website: http://www.rha-audio.com
MSRP: $119.95