Does the Schiit Fulla 4 drive the Audio-Technica ATH-R70x?

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

Verdict

Marginal

The Schiit Fulla 4 marginally drives the Audio-Technica ATH-R70x; barely reaches target SPL (~1.0 dB headroom at 600 ohms; needs ~15.8 mW, delivers 20 mW). (Amp power at 600 ohms is estimated from its published figure at a nearby load.)

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

Power Headroom

Headroom: 1.0 dB 0 · target 1.0 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 20 mW at 600 Ω (+1.0 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 ↗
Schiit Fulla 4 Dac Amp · Single Ended
Output impedance manufacturer 0.5 Ω
Power @ 16 Ω 300 mW
Power @ 32 Ω 200 mW
Power @ 50 Ω 150 mW
Power @ 300 Ω 40 mW
Power @ 600 Ω 20 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.
Schiit Fulla 4 manufacturer spec: 300/200/150/40 mW at 16/32/50/300 Ω. NOTE: prior project fixture used 400/300/220/40 — those figures match the Fulla 3 or an earlier revision; updated to Fulla 4 (current product). Output impedance from Schiit spec. · 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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