Short answer
Both are dongles, $70 against $69.
The iBasso DC03 Pro reaches 100 dB on 560 of the 567 models here, the DUNU DTC 480 on 554.
| Specification | DUNU DTC 480 | iBasso DC03 Pro |
|---|---|---|
| Power into 32Ω | 65 mW | 98 mW |
| Power into 150Ω | 14 mW | 21 mW |
| Power into 300Ω | 6.9 mW | 10 mW |
| Power into 600Ω | 3.5 mW | 5.2 mW |
| Output impedance | not published | 0.12 Ω |
| Output noise | not published | 0.9 µV |
| Price | $70 | $69 |
| Headphones it reaches 100 dB on out of 567 | 554 | 560 |
Not published means the maker leaves it out, so that axis cannot be compared.
| Balanced | DUNU DTC 480 | iBasso DC03 Pro |
|---|---|---|
| Socket | 4.4mm | no separate rating |
| Power into 32Ω | 150 mW | — |
| Power into 300Ω | 16 mW derived | — |
| Output impedance | not published | — |
| Output noise | not published | — |
| Headphones it reaches 100 dB on out of 567 | 563 | — |
Only the DUNU DTC 480 has a separate balanced rating from its maker; through it, it reaches 100 dB on 563 of the 567 models here. The iBasso DC03 Pro may still have a balanced socket — its spec sheet simply gives no figure for one, so there is nothing to put beside it. Derived figures are worked out from the loads the maker did publish.
| Load | DUNU DTC 480 | iBasso DC03 Pro |
|---|---|---|
| 32 Ω | Published | Published |
| 150 Ω | Derived | Derived |
| 300 Ω | Derived | Derived |
| 600 Ω | Derived | Derived |
Both makers publish a power rating. DUNU DTC 480 publishes at 32 Ω; iBasso DC03 Pro at 32 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.
6 headphones reach 100 dB on the iBasso DC03 Pro but not on the DUNU DTC 480 — HiFiMAN HE-6se V2, HiFiMAN HE6 Remastered, HiFiMAN Susvara, 3 more.
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 Sennheiser HD 600: iBasso DC03 Pro has +2 dB of headroom there against +0 dB. 2 dB is about 1.5 times the power, which matters for peaks rather than for how loud the music sits.
The hiss columns are empty for DUNU DTC 480 because that maker publishes no output noise figure.
| Headphone | Impedance | Needs | DUNU DTC 480 headroom | iBasso DC03 Pro headroom | DUNU DTC 480 hiss | iBasso DC03 Pro hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +27 dB | +28 dB | not published | 14 dB |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +7 dB | +8 dB | not published | -6 dB |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +16 dB | +18 dB | not published | -8 dB |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +11 dB | +13 dB | not published | -13 dB |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +8 dB | +10 dB | not published | -14 dB |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +4 dB | +6 dB | not published | -20 dB |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | +0 dB | +2 dB | not published | -24 dB |
| HiFiMAN Susvara | 60 Ω | 50 mW | -2 dB | +0 dB | not published | -26 dB |
The DUNU DTC 480 costs $1 more than the iBasso DC03 Pro, and on these three axes the money buys nothing: among the 567 models here there is not one that the DUNU DTC 480 handles and the iBasso DC03 Pro does not — not on power, not on the one-eighth rule, not on hiss. The traffic runs the other way: the cheaper iBasso DC03 Pro drives 6 models to 100 dB that the DUNU DTC 480 does not.
Only published figures count here; blank axes are counted separately.
Each in full: DUNU DTC 480 and iBasso DC03 Pro.