In this review, I’m looking at the Hidizs MD4 earphones. The MD4 features 4 balanced armature (BA) drivers, a 3-way crossover and dual tuning switches for a total of 4 different sound styles. It’s priced at $169.
Disclaimer: This sample was provided by Hidizs for an honest review. All observations and opinions here are my own based on my experience with the product.
Hidizs MD4 Review
Smooth, refined and versatile, the MD4 is a refreshing and polished IEM.
Drivers: 4 BA drivers (high-frequency x1, midrange x1, low-frequency x2)
Frequency response: 20Hz-40kHz
Cable: Silver-plated OFC
What’s In the Box
Hidizs MD4 earphones
Detachable 2-pin cable
Faux leather carrying case
9x pairs of silicone eartips
Cleaning brush/switch tool
Documentation & warranty
MD4’s shells are made from an aluminium alloy and have a smooth matte finish. The IEM is available in 3 colours: black, indigo and white. I received the white unit which has silver shells and a pearlescent white celluloid faceplate with a rose gold Hidizs logo and frame.
One of the MD4’s highlights is the 2 tuning switches on each earpiece. These provide a total of 4 different sound styles: balanced, warm, treble and bass. Internally, there are 4 custom-designed balanced armature drivers combined with a 3D-printed straight acoustic sound tube.
The aluminium nozzles have a solid lip for holding your eartips firmly in place and a mesh cover to protect the IEM from ear wax and dirt. The overall build quality looks and feels premium for something in this price range.
I find the MD4 to be really comfortable and they fit snugly in my ears. The passive noise isolation is well above average thanks to the non-vented nature of the shells. Even with music playing quietly I can barely hear any external noises at all.
The MD4 comes with a silver-plated oxygen-free 2-pin cable. It’s a 4-strand cable with an aluminium plug, Y-split and chin slider. The transparent plastic 2-pin connector housings are colour coded with a red or blue dot for the right and left sides respectively. The cable is very lightweight and has good handling.
With a sensitivity of 102dB and just 8Ω impedance, the Hidizs MD4 is an efficient IEM. It does not require extra amplification and will work fine straight out of a smartphone or low-powered dongle DAC.
The MD4’s general presentation is balanced and has a spacious, airy character. It sounds clean from top to bottom with a near-neutral note weight and black background. As a result, the MD4 is a highly resolving IEM. Furthermore, it has very good detail retrieval so you can expect to hear small nuances that other earphones might miss.
The MD4 has 4 different sound settings: Balanced, Warm, Treble and Bass. You can change between the different sound profiles by using the 2 switches on the IEMs. Unlike so many nozzle filter IEMs, the MD4 uses circuitry for its tuning profiles.
The results are palpably better than most nozzle solutions; there are significant differences for each setting, whereas nozzle filters tend to have only minute changes affecting the upper midrange and treble. Each of MD4’s sound profiles has a unique character, increasing its versatility even more. For the record, I enjoyed all of the different tunings but my favourite is the “Treble” setting.
In typical BA driver fashion, the bass is tight and fast. It’s somewhat light in quantity but has natural attack and decay speeds. As a result, bass notes have accurate thickness yet there’s no bleeding into the midrange whatsoever. This is about as clean as bass gets while still providing ample warmth and body.
The bass is textured and shows good depth. In Slowly Rolling Camera’s “Eight Days”, the MD4 delivers the drums with sufficient impact and meaty goodness. You can feel the fullness in the bass but it doesn’t cause any smearing or blanket the mids. It’s not something for bassheads but listeners looking for a mature sound will appreciate the tone and control.
MD4’s mids are a pleasing mix of natural warmth and spacious clarity. Vocals aren’t especially upfront nor are they recessed but have good density and articulation. Also absent is the usual large upper midrange peak. As a result, the midrange doesn’t get shouty, even if it doesn’t always demand your utmost attention.
It’s an organic midrange that aims for an organic tone over absolute contrast which I tend to prefer over a more clinical approach. However, the MD4’s mids don’t sound coloured or oversaturated. In fact, there’s great spacing between vocals and instruments which prevents excessive smoothing and enhances the overall resolution.
The violin and piano in Anathema’s “Fragile Dreams” sound rich and full-bodied while the acoustic guitar and vocals are crisp. I like how the vocals remain clear and the focus of the song even when the drums and all the instruments are playing simultaneously in the latter stages of the track.
The treble is as impressive in itself as the overall presentation. It’s deliciously smooth yet airy and open at the same time, especially in the “treble” switch setting. Trebleheads might wish for more energy in the highs but I personally find them to have just the right amount of bite and smoothness.
The level of detail retrieval is good but MD4 is not an ultra-detailed IEM. Instead, it has an extremely even treble without any noticeable peaks or sharpness whatsoever. You can turn the volume right up without needing to worry about sizzle or sibilance.
Soundstage and Technicalities
The MD4’s soundstage is larger than average in dimensions. It creates a rounded space that’s slightly wider than deep but still reaches well forward of the listener. The stage position is neutral as if you were sitting a few rows back from the front.
The imaging gives a clear indication of the positions and boundaries of individual instruments. This comes from the speed of transients combined with above-average instrument separation, spacing and clarity.
The IKKO OH10 (review here) is a V-shaped IEM with lots of bass and a wide soundstage. It has a very meaty bass compared to the MD4 and it has powerful sub-bass that will rattle your skull. The OH10 should satisfy most bassheads while the MD4 will leave them wanting more.
OH10’s midrange is recessed but lovely and clear with good instrument separation. The MD4’s midrange is more forward with thicker notes and a more intimate presentation. OH10 has thinner vocals where the MD4 is more upfront and balanced alongside the bass and treble.
OH10’s treble is more energetic and forward. In conjunction with the recessed midrange, it makes for an expansive soundstage, albeit one that is slightly lacking in warmth compared to the MD4’s more full-bodied approach.
The Moondrop KATO (review here) has a single dynamic driver. Its bass has more impact and authority courtesy of the dynamic driver that moves a lot more air.
KATO’s midrange is slightly leaner than the MD4 but it has more bass and less treble. The result is a midrange with more clarity but less overall resolution than the MD4. Both IEMs have smooth treble that’s neither sparkly nor sibilant but the KATO has more upper treble presence.
KATO’s soundstage is a bit smaller than the MD4. Its stage is a tad narrower too but imaging and placement are on par with the MD4.
The Hidizs MD4 makes a strong statement, especially considering this is the brand’s first all-BA IEM (as far as I know). Hidizs’ engineers have produced a mature, balanced sound that’s not only warm and organic but also has good clarity and an accurate tone.
With the option of 4 different sound styles, it’s versatile too. The build quality and comfort are both great plus the included accessories are well-rounded. If you’re looking for a smooth but detailed sound and something that’s not riding the Harman bandwagon, the Hidizs MD4 is a very valid option.