DUNU DTC 480 vs HiBy FC4

Short answer

More power: the HiBy FC4, with 110 mW into 32 Ω; the DUNU DTC 480 has 65 mW (balanced: 340 mW against 150 mW). The HiBy FC4 drives 7 headphones to 100 dB that the DUNU DTC 480 cannot (HiFiMAN HE-6se V2, HiFiMAN HE6 Remastered, HiFiMAN Susvara, 4 more).
Hiss with sensitive IEMs: cannot be compared — the maker of the DUNU DTC 480 publishes no noise figure.
Price: the HiBy FC4 costs $29 more; what that buys on these numbers is set out further down, under What the price difference buys.

Both are dongles, $70 against $99.

The HiBy FC4 reaches 100 dB on 561 of the 567 models here, the DUNU DTC 480 on 554.

Side by side

Every published figure, next to each other

Specification	DUNU DTC 480	HiBy FC4
Power into 32Ω	65 mW	110 mW
Power into 150Ω	14 mW	23 mW
Power into 300Ω	6.9 mW	12 mW
Power into 600Ω	3.5 mW	5.9 mW
Output impedance	not published	not published
Output noise	not published	1.7 µV
Price	$70	$99
Headphones it reaches 100 dB on out of 567	554	561

Not published means the maker leaves it out, so that axis cannot be compared.

Balanced output

The 4.4 mm or XLR socket, rated on its own

Balanced	DUNU DTC 480	HiBy FC4
Socket	4.4mm	4.4mm
Power into 32Ω	150 mW	340 mW
Power into 300Ω	16 mW derived	36 mW derived
Output impedance	not published	not published
Output noise	not published	2.2 µV
Headphones it reaches 100 dB on out of 567	563	565

Through the balanced sockets the HiBy FC4 reaches 100 dB on 565 of the 567 models here and the DUNU DTC 480 on 563. Derived figures are worked out from the loads the maker did publish.

How solid these numbers are

Where each power figure comes from

Load	DUNU DTC 480	HiBy FC4
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; HiBy FC4 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.

What the labels mean.

What separates them

The headphones that tell them apart

7 headphones reach 100 dB on the HiBy FC4 but not on the DUNU DTC 480 — HiFiMAN HE-6se V2, HiFiMAN HE6 Remastered, HiFiMAN Susvara, 4 more.

554 of the 567 models here reach 100 dB on both.

On real headphones

Headroom and hiss on 8 models, both sources

Headroom is at a 100 dB SPL peak.

The widest gap on the list is the Sennheiser HD 600: HiBy FC4 has +2 dB of headroom there against +0 dB. 2 dB is about 1.7 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	HiBy FC4 headroom	DUNU DTC 480 hiss	HiBy FC4 hiss
Shure SE846	9 Ω	0.04 mW	+27 dB	+29 dB	not published	19 dB
Campfire Audio Andromeda 2020	9 Ω	4.0 mW	+7 dB	+9 dB	not published	-1 dB
Audeze LCD-2 Classic	70 Ω	0.79 mW	+16 dB	+18 dB	not published	-3 dB
Beyerdynamic DT 1990 Pro (250Ω)	250 Ω	0.63 mW	+11 dB	+13 dB	not published	-7 dB
HiFiMAN HE400se	25 Ω	7.9 mW	+8 dB	+10 dB	not published	-8 dB
Audio-Technica ATH-R70X	470 Ω	1.6 mW	+4 dB	+7 dB	not published	-14 dB
Sennheiser HD 600	300 Ω	6.6 mW	+0 dB	+2 dB	not published	-18 dB
HiFiMAN Susvara	60 Ω	50 mW	-2 dB	+1 dB	not published	-20 dB

What the price difference buys

The gap in dollars, against the gap in numbers

The HiBy FC4 costs $29 more than the DUNU DTC 480. Out of the 567 models here, that difference buys 7 more models driven to 100 dB.

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: DUNU DTC 480 and HiBy FC4.