The Sennheiser HD 480 PRO is 130Ω with a sensitivity of 98.0 dB/mW, which is 106.9 dB/V. To reach 100 dB SPL — genuinely loud, louder than most people listen — it needs 1.6 mW, or 0.45 V across the drivers.
That puts it in the easy category. A phone, a laptop headphone jack or the cheapest USB dongle will drive it to painful levels. Of the 280 sources in the database, 256 have at least 10 dB of headroom and another 24 have enough. The cheapest portable source that does the job is the Apple USB-C dongle (US) at $9.
Sensitivity here is in dB per milliwatt. Why the unit matters.
Sennheiser publishes this directly as 98 dB SPL/mW (1 kHz / 1 mW), per milliwatt, so nothing was converted.
The maker adds a power recommendation of its own: Power consumption (Amp): 300 mW (100 h, noise IEC60268)
Source: sennheiser.com. How this data was built.
| As it is labelled | As printed | Tolerance | Standard |
|---|---|---|---|
| Audio frequency response | 3 Hz - 28,700 Hz | not printed | not printed |
Sennheiser prints 3 Hz - 28,700 Hz for the Sennheiser HD 480 PRO, under the heading “Audio frequency response”. Source: sennheiser.com.
No tolerance is printed with it, so “3 Hz - 28,700 Hz” says nothing about how loud this headphone actually is at 3 Hz.
Only what the maker printed; maker by maker.
| Level | What it is | Power | Voltage | Current |
|---|---|---|---|---|
| 85 dB SPL | quiet background listening | 0.05 mW | 81 mV | 0.6 mA |
| 95 dB SPL | normal listening | 0.50 mW | 0.26 V | 2.0 mA |
| 100 dB SPL | loud listening | 1.6 mW | 0.45 V | 3.5 mA |
| 105 dB SPL | very loud | 5.0 mW | 0.81 V | 6.2 mA |
| 110 dB SPL | peaks on dynamic music | 16 mW | 1.44 V | 11.0 mA |
Most people listen between 75 and 85 dB; the 100 dB row leaves room for peaks.
The 15 cheapest of the 280 sources here that reach 100 dB SPL into 130Ω with at least 10 dB of headroom and no known hiss or output-impedance problem with these headphones. All 280 sources, judged for these headphones.
| Source | Type | Price | Power into 130Ω | Headroom | Verdict |
|---|---|---|---|---|---|
| FiiO KA11 | USB dongle | $29 | 50 mW | +15 dB | Comfortable |
| Tanchjim Stargate II | USB dongle | $40 | 18 mW | +11 dB | Comfortable |
| ddHiFi TC35AL | USB dongle | $46 | 52 mW | +15 dB | Comfortable |
| ddHiFi TC35Air | USB dongle | $46 | 52 mW | +15 dB | Comfortable |
| Fosi Audio N3 | Bluetooth receiver | $50 | 34 mW | +13 dB | Comfortable |
| Hidizs SD2 | USB dongle | $50 | 17 mW | +10 dB | Comfortable |
| FiiO BTR13 | Bluetooth receiver | $59 | 24 mW | +12 dB | Comfortable |
| iFi GO link | USB dongle | $59 | 22 mW | +11 dB | Comfortable |
| Kiwi Ears Allegro Pro | USB dongle | $60 | 17 mW | +10 dB | Comfortable |
| Tempotec Sonata BHD Pro | USB dongle | $60 | 69 mW | +16 dB | Comfortable |
| ddHiFi TC35Pro (Mountain2) | USB dongle | $66 | 16 mW | +10 dB | Comfortable |
| iBasso DC03 Pro | USB dongle | $69 | 24 mW | +12 dB | Comfortable |
| DUNU DTC 480 | USB dongle | $70 | 16 mW | +10 dB | Comfortable |
| EPZ TP35 Pro | USB dongle | $70 | 28 mW | +12 dB | Comfortable |
| Tanchjim Space | USB dongle | $70 | 31 mW | +13 dB | Comfortable |
Hiss. At 106.9 dB/V these are sensitive enough to reveal a source's own noise floor. The noisiest source in the database, the Schiit Mjolnir 3, would put its hiss at roughly 15 dB SPL in these headphones — clearly audible in quiet passages. Check your own source.
Output impedance. At 130Ω these want a source output impedance below 16.25Ω to satisfy the one-eighth rule; 17 of the 192 sources that publish one miss it. Check yours here.
130Ω · 96.0 dB/mW · Moderate
See requirements →120Ω · 100.8 dB/mW · Easy
See requirements →120Ω · 98.7 dB/mW · Easy
See requirements →32Ω · 92.0 dB · Easy
See requirements →80Ω · 96.0 dB · Easy
See requirements →80Ω · 96.0 dB · Easy
See requirements →Compared with its stablemates: vs HD 280 Pro · vs HD 58X Jubilee (Drop) · vs HD 600.