Does the FiiO K7 drive the Audio-Technica ATH-R70x?

Computed from rated specifications · target SPL 110 dB · load 600 Ω

Verdict

Adequate

The FiiO K7 adequately drives the Audio-Technica ATH-R70x with limited margin (~6.5 dB headroom at 600 ohms; needs ~15.8 mW, delivers 70 mW). (Amp power at 600 ohms is estimated from its published figure at a nearby load.)

Headroom
6.5 dB
Required (110 dB SPL)
15.8 mW
Delivered (@ 600 Ω)
70 mW *est.
Required voltage
2.73 Vrms

Power Headroom

Headroom: 6.5 dB 0 · target 6.5 dB below target marginal adequate ample -14 dB +10 +20 +36 dB

Scale shows dB headroom above the 15.8 mW required to reach 110 dB SPL. Amp delivers 70 mW at 600 Ω (+6.5 dB above target). Power figure estimated from an adjacent published load.

Audio-Technica ATH-R70x Dynamic · over-ear
Impedance 470.0 Ω rated
Sensitivity 98.0 dB/mW rated
Driver Dynamic
Spec basis Rated
Rated: Audio-Technica official spec (470 Ω, 98 dB/mW at 1 kHz). RAA has no measurement page. · Source ↗
FiiO K7 Dac Amp · Single Ended
Output impedance manufacturer 1.0 Ω
Power @ 32 Ω 1220 mW
Power @ 300 Ω 140 mW
Power @ 600 Ω 70 mW *est.
Power source Manufacturer
* Loads marked "est." are derived from the published voltage ceiling at a lower-impedance load (V = √(P·R) → P_higher = V²/R_higher). All derivations are upward only.
FiiO K7 SE headphone output from manufacturer spec page (fiio.com/k7_parameters): L+R ≥ 1220 mW+1220 mW @ 32 Ω, L+R ≥ 140 mW+140 mW @ 300 Ω (THD+N<1%). Output impedance <1 Ω @ 32 Ω from manufacturer. 600 Ω derived from 300 Ω. · Source ↗
Power figure note

The amp's power at 600 Ω was not published directly — it was derived from the voltage ceiling at a published lower-impedance load. The actual delivered power may differ modestly.

Where to buy

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