Short answer
Both are dongles, $70 against $79.
The EPZ TP35 Pro reaches 100 dB on 561 of the 567 models here, the FiiO KA13 on 555.
| Specification | EPZ TP35 Pro | FiiO KA13 |
|---|---|---|
| Power into 32Ω | 112 mW | 50 mW |
| Power into 150Ω | 24 mW | 10 mW |
| Power into 300Ω | 12 mW | 5.0 mW |
| Power into 600Ω | 6.0 mW | 2.5 mW |
| Output impedance | not published | 1.7 Ω |
| Output noise | not published | 2.5 µV |
| Price | $70 | $79 |
| Headphones it reaches 100 dB on out of 567 | 561 | 555 |
Not published means the maker leaves it out, so that axis cannot be compared.
| Balanced | EPZ TP35 Pro | FiiO KA13 |
|---|---|---|
| Socket | 4.4mm | 4.4mm |
| Power into 32Ω | 262 mW | 260 mW |
| Power into 300Ω | 28 mW derived | 20 mW |
| Output impedance | not published | 1.8 Ω |
| Output noise | not published | 4.6 µV |
| Headphones it reaches 100 dB on out of 567 | 565 | 565 |
Through the balanced sockets the two are level on the same test: each reaches 100 dB on 565 of the 567 models here. Derived figures are worked out from the loads the maker did publish.
| Load | EPZ TP35 Pro | FiiO KA13 |
|---|---|---|
| 32 Ω | Published | Published |
| 150 Ω | Derived | Derived |
| 300 Ω | Derived | Published |
| 600 Ω | Derived | Derived |
Both makers publish a power rating. EPZ TP35 Pro publishes at 32 Ω; FiiO KA13 at 32 Ω and at 300 Ω. The other rows are worked out from those.
So the two columns are not equally firm row by row: at 300 Ω only the FiiO KA13 figure is the maker’s own. On those rows the derived number is the one to doubt first.
7 headphones reach 100 dB on the EPZ TP35 Pro but not on the FiiO KA13 — Beyerdynamic DT 880 Edition (600Ω), Beyerdynamic DT 990 Edition (600Ω), HiFiMAN HE-6se V2, 4 more.
1 headphone reaches 100 dB on the FiiO KA13 but not on the EPZ TP35 Pro — Symphonium Zenith.
554 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 Audio-Technica ATH-R70X: EPZ TP35 Pro has +7 dB of headroom there against +3 dB. 4 dB is about 2.4 times the power, which matters for peaks rather than for how loud the music sits.
The hiss columns are empty for EPZ TP35 Pro because that maker publishes no output noise figure.
| Headphone | Impedance | Needs | EPZ TP35 Pro headroom | FiiO KA13 headroom | EPZ TP35 Pro hiss | FiiO KA13 hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +29 dB | +30 dB damping | not published | 22 dB |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +9 dB | +10 dB damping | not published | 2 dB |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +18 dB | +15 dB | not published | 1 dB |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +14 dB | +10 dB | not published | -4 dB |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +10 dB | +8 dB | not published | -5 dB |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +7 dB | +3 dB | not published | -11 dB |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | +3 dB | -1 dB | not published | -15 dB |
| HiFiMAN Susvara | 60 Ω | 50 mW | +1 dB | -3 dB | not published | -17 dB |
The FiiO KA13 costs $9 more than the EPZ TP35 Pro. Out of the 567 models here, that difference buys 1 more model driven to 100 dB.
It does not run one way only: the cheaper EPZ TP35 Pro drives 7 models to 100 dB that the FiiO KA13 does not, which is the part worth checking against your own headphones before paying the difference.
Only published figures count here; blank axes are counted separately.
Each in full: EPZ TP35 Pro and FiiO KA13.