Short answer
Both are desktop DAC/amps, $176 against $199.
On raw power they are level: each reaches 100 dB on 567 of the 567 non-electrostatic models here.
| Specification | FiiO K11 R2R | FiiO K7 |
|---|---|---|
| Power into 32Ω | 460 mW | 1.2 W |
| Power into 150Ω | 99 mW | 269 mW |
| Power into 300Ω | 50 mW | 140 mW |
| Power into 600Ω | 25 mW | 70 mW |
| Output impedance | 1.0 Ω | 1.0 Ω |
| Output noise | 7.2 µV | 3.1 µV |
| Price | $176 | $199 |
| Headphones it reaches 100 dB on out of 567 | 567 | 567 |
| Balanced | FiiO K11 R2R | FiiO K7 |
|---|---|---|
| Socket | 4.4mm | 4.4mm |
| Power into 32Ω | 1.3 W | 2.0 W |
| Power into 300Ω | 220 mW | 560 mW |
| Output impedance | 1.5 Ω | 1.0 Ω |
| Output noise | 14.1 µV | 5.1 µV |
| Headphones it reaches 100 dB on out of 567 | 567 | 567 |
Through the balanced sockets the two are level on the same test: each reaches 100 dB on 567 of the 567 models here.
| As published | FiiO K11 R2R | FiiO K7 |
|---|---|---|
| DAC | FiiO-developed fully differential 24-bit R2R (discrete resistor arrays) | Dual AK4493SEQ |
| Outputs | 6.35 mm SE, 4.4 mm balanced, RCA line out, coaxial out (RCA, USB mode only) | 6.35 mm SE, 4.4 mm balanced, RCA line out |
| Inputs | USB-C, optical, coaxial (RCA) | USB-B, optical (Toslink), coaxial (RCA), analog line in (RCA) |
| Bluetooth | not published | K7 BT version only: Bluetooth 5.1, LDAC/aptX Adaptive/aptX/aptX HD/aptX LL/AAC/SBC |
| Formats | USB: 384 kHz/32-bit, DSD256 | USB: PCM 384 kHz/32-bit, DSD256 |
| Power supply | External 12 V / 2 A adapter | External 12 V / 2 A adapter (12V/24W supply included) |
| Gain | Low / Medium / High | Low / High |
| Weight | 420 g | 610 g |
| Dimensions | 147 × 133 × 32.3 mm (including feet) | About 120 × 168 × 55 mm |
Copied from the makers’ own pages: fiio.com/k11r2r_parameters, fiio.com/k7, fiio.com/k7_parameters. Battery life is the maker’s own test figure.
| Load | FiiO K11 R2R | FiiO K7 |
|---|---|---|
| 32 Ω | Published | Published |
| 150 Ω | Derived | Derived |
| 300 Ω | Published | Published |
| 600 Ω | Derived | Derived |
Both makers publish a power rating. FiiO K11 R2R publishes at 32 Ω and at 300 Ω; FiiO K7 at 32 Ω and at 300 Ω. The other rows are worked out from those.
The two publish at the same loads, which is the one case where the rows of this table can be read straight across.
On power they are interchangeable across this whole database: there is no headphone here that one reaches 100 dB on and the other does not.
111 headphones stay below the audible-hiss threshold on the FiiO K7 but cross it on the FiiO K11 R2R (64 Audio Aspire 1, 64 Audio Nio, 64 Audio Ocean, 108 more).
567 of the 567 models here reach 100 dB on both.
Headroom is at a 100 dB SPL peak.
The widest gap on the list is the Sennheiser HD 600: FiiO K7 has +13 dB of headroom there against +9 dB. 4 dB is about 2.8 times the power, which matters for peaks rather than for how loud the music sits.
Hiss below about 20 dB SPL is inaudible in a quiet room.
| Headphone | Impedance | Needs | FiiO K11 R2R headroom | FiiO K7 headroom | FiiO K11 R2R hiss | FiiO K7 hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +40 dB | +39 dB | 32 dB | 24 dB |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +20 dB | +19 dB | 12 dB | 4 dB |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +24 dB | +29 dB | 10 dB | 2 dB |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +20 dB | +24 dB | 5 dB | -2 dB |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +18 dB | +21 dB | 4 dB | -3 dB |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +13 dB | +18 dB | -2 dB | -9 dB |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | +9 dB | +13 dB | -6 dB | -13 dB |
| HiFiMAN Susvara | 60 Ω | 50 mW | +7 dB | +11 dB | -8 dB | -15 dB |
The FiiO K7 costs $23 more than the FiiO K11 R2R. Out of the 567 models here, that difference buys 111 more models kept below the audible-hiss threshold.
Nothing runs the other way: there is no axis here on which the cheaper of the two does better.
Only published figures count here; blank axes are counted separately.
Each in full: FiiO K11 R2R and FiiO K7.