AimBench

Best DAC/amp for the Truthear Hexa (IEM)

The Truthear Hexa (IEM) is a 20.5Ω IEM pair. To hit clean 110 dB transient peaks — the headroom that keeps footsteps and gunfire punchy, not just loud — it needs about 4.9 mW into that load. The pick that does it most affordably is the Apple USB-C 3.5mm dongle.

What the Hexa (IEM) needs

SpecValueWhy it matters
Impedance20.5 ΩEasy-ish load, but damping still matters
Sensitivity120 dB/VHow loud per unit power
Power for 110 dB peaks~4.9 mWTransient headroom for positional cues
Amp output impedance≤ 3 Ω idealThe 8:1 damping rule — keeps the tuning flat

Sound character — footsteps, general use & music

AxisGradeWhat it means
Footsteps (positional)3/5The ONLY competitive axis — and it saturates: any clean open-back clears the bar, so more above baseline buys little advantage.
General use4/5All-round daily versatility — comfort/preference, not a competitive edge.
Music5/5Tonal enjoyment — preference, never advantage.

IEM; in-head narrow stage but precise imaging, excellent neutral tone (Graded 1–5 relative to our catalog; sourced from measurement/review consensus.)

DAC/amps ranked for the Hexa (IEM)

The 8:1 damping rule
For tight, neutral bass the headphone's impedance should be at least the amp's output impedance (Zout). Below that, a high-Zout source loses control of the driver — bass bloats and the frequency response shifts with the load. AimBench checks this ratio as a pass/fail sufficiency gate, not a graded score.
DAC / AmpPower @ 20.5ΩHeadroomDampingVerdict
Apple USB-C 3.5mm dongle30 mW+8 dB23:1Drives it comfortably
Schiit Magni Unity2500 mW+27 dB205:1Drives it comfortably
JDS Labs Atom Amp 22600 mW+27 dB29:1Drives it comfortably
FiiO K5 Pro ESS1500 mW+25 dB17:1Drives it comfortably
Topping L30 II2500 mW+27 dB205:1Drives it comfortably
Creative Sound Blaster G6130 mW+14 dB21:1Drives it comfortably
Topping DX3 Pro+1800 mW+26 dB205:1Drives it comfortably
FiiO K71220 mW+24 dB21:1Drives it comfortably
FiiO K111400 mW+25 dB7:1Adequate

"Headroom" is power available vs the ~4.9 mW needed for 110 dB peaks (more = cleaner transients). "Damping" is the headphone impedance ÷ amp output impedance — at least 8:1 keeps the frequency response flat. Specs are sourced; the target SPL and 8:1 rule are the declared model.

The pick: Apple USB-C 3.5mm dongle

For the Truthear Hexa (IEM), the Apple USB-C 3.5mm dongle delivers ~30 mW into 20.5Ω (+8 dB of headroom) at a 23:1 damping ratio — clean, loud, and tonally neutral. It's the most cost-effective amp here that drives these without compromise.

Specs are sourced (manufacturer sheets + RTINGS / Audio Science Review, each with a verified date in our catalog). Buy links are affiliate links to your regional store — AimBench may earn a commission at no cost to you.

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