In this article, I review the Tanchjim Force open-back dual dynamic driver IEM. The Force features dual dynamic drivers and a custom cable by Effect Audio. It’s priced at $279 USD.

Disclaimer: This sample was provided by Tanchjim for an honest review. All observations and opinions here are my own, based on my experience with the product.

Tanchjim Force

Specifications

Drivers: 8.2mm + 10mm Dual Dynamic Drivers
Driver Technology: DMT 4 Ultra
Driver Material: PU Suspended Edge + Beryllium/Titanium-Coated PET Dome
Impedance: 17Ω ±10%
Sensitivity: 120dB/Vrms
Frequency Response: 8Hz – 48kHz

Inside the Box

• Tanchjim Force IEM
• Detachable 0.78mm 2-pin cable
• USB-C DSP, 4.4mm and 3.5mm plugs
• 6* pairs of silicone eartips
• Faux leather carrying case

Design

The Tanchjim Force sticks with the brand’s familiar styling. It has a semi-open back design that helps with soundstage and air pressure control. The faceplates are made from aluminium alloy, while the shells are crafted from clear resin. It’s a fairly understated and industrial look, but I think it comes across as classy.

I also found the Force to be comfortable, with the longer nozzles allowing me to use slightly smaller eartips than usual — a nice change. Despite the semi-open design, passive noise isolation is still quite decent.

The included cable is a premium one made by Effect Audio and comes with USB-C DSP, 4.4mm, and 3.5mm terminations. While the cable isn’t the most supple, it’s thankfully free of microphonics and handles reasonably well.

Sound

Sources used for testing include the iBasso DX260 MK2, D&A Alpha Pro and xDuoo XD05 Bal2. The Tanchjim Force is easy to drive, so you don’t need to worry about what audio source you plug it into.

The Force has a balanced, spacious and somewhat airy sound. It has good extension in the lows, breathy mids and a light, fatigue-free treble.

Bass

The Force reaches deep when called for, with sub-bass that carries real authority yet never feels exaggerated. It’s tight and effortless, the kind of low end that rumbles when needed but doesn’t hang around longer than it should. The mid-bass sits closer to neutral, giving just enough punch to drive the rhythm without smearing into the mids.

What I really like here is how natural it feels – the sub-bass has weight and power but blends so smoothly with the rest of the tuning that it never comes across as an add-on. Instead, it underpins the music in a way that feels cohesive and musical, giving tracks a solid foundation without tipping the balance.

Midrange

The midrange comes across with a natural warmth that gives instruments and voices plenty of body without sounding heavy. Female vocals are smooth and sweet, lifted just enough to give them air and presence without tipping into sharpness.

Strings sound particularly pleasing – violins have a singing quality that stays graceful, while cellos dig in with authority yet keep their agility intact. Piano notes land with convincing weight and decay naturally, never feeling abrupt or artificial. It all comes together in a way that feels cohesive and musical, with enough clarity to pick up detail but a tonality that stays easy and lifelike.

Treble

The slight softening of the treble means the Force isn’t an ultra-detailed monitor, and some micro-details are unresolved. However, this can be remedied by using the DSP plug if you’re willing to trade some of the musicality. Softer vocal notes have a delicate, breathy quality.

Soundstage & Technicalities

The Tanchjim Force has a wide stage, enhanced by both its semi-open-back nature and near-neutral tonality. It handles complexities well without getting congested and maintains good instrument separation. The imaging is precise and creates a good spatial representation of the stage with good note density.

Verdict

The Tanchjim Force is a refreshing release that combines solid sound with a high level of flexibility. Out of the box, it’s tuned in a way that works well across different genres, but the addition of the USB-DSP termination and EQ support means you can easily shape it to suit your own taste. On top of that, it’s comfortable, well-built, and straightforward to use. This is another release from Tanchjim that I’m happy to recommend.