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Comparison
A 4.4 mm balanced cable keeps the left and right channels’ return wires separate, and most players drive their balanced output harder: across the ten players and dongles below, the 4.4 mm output gives about 1.5 to 4.5 times the power of 3.5 mm. That headroom matters for harder-to-drive earphones and headphones. With sensitive IEMs, 3.5 mm is often all you need, and on several players the balanced output has a higher output impedance, which can shift a multi-driver IEM’s tuning more than any cable can.
The numbers
| Player or dongle | 3.5 mm output | 4.4 mm output | Output impedance (3.5 / 4.4) | Mode |
|---|---|---|---|---|
| Sony NW-ZX707 | 50 mW (16 Ω, JEITA) | 230 mW (16 Ω, JEITA) | not published | High gain |
| Sony NW-WM1AM2 | 60 mW (16 Ω, JEITA) | 250 mW (16 Ω, JEITA) | not published | High gain |
| FiiO M11S | ≥ 200 mW @ 32 Ω | ≥ 670 mW @ 32 Ω | ≤ 1.5 Ω / ≤ 2.6 Ω | — |
| FiiO M15S | 580 mW @ 32 Ω | 1200 mW @ 32 Ω | ≤ 1.4 Ω / ≤ 2.3 Ω | Ultra-high gain, USB power |
| FiiO BTR7 | ≈ 160 mW @ 32 Ω | ≈ 320 mW @ 32 Ω | ≤ 1.2 Ω / <2.8 Ω | — |
| FiiO KA17 | 270 mW @ 32 Ω | 650 mW @ 32 Ω | < 1 Ω / <1.5 Ω | Desktop mode, high gain |
| Shanling M3 Ultra | 140 mW @ 32 Ω | 260 mW @ 32 Ω | < 1 Ω / <1 Ω | High gain |
| Shanling UA5 | 137 mW @ 32 Ω | 211 mW @ 32 Ω | not published | — |
| Astell&Kern A&norma SR35 | 2.1 Vrms (no load) | 4 Vrms (no load) | 1.1 Ω / 2.7 Ω | Normal gain |
| Moondrop Dawn Pro | 2 Vrms | 4 Vrms | not published | — |
Each maker’s own figures, units and load; not converted. Sony figures are from Sony’s regional spec pages. Accessed 25 October 2026.
What changes
In a balanced cable each channel has its own return wire, instead of a shared ground. That removes one shared path between left and right.
General referenceGeneral referenceMost players drive the 4.4 mm output with about 1.4–2× the voltage, which is 1.5–4.5× the power in the table above.
Null AudioCalculated by Null Audio from the table aboveOn several players the balanced output impedance is higher (FiiO M11S: ≤ 2.6 Ω balanced, ≤ 1.5 Ω on 3.5 mm). With a multi-driver balanced-armature IEM, 1–2 Ω of output impedance tilts the frequency response by roughly 1.4–3.8 dB on its own, far more than the cable.
Null AudioCalculated by Null AudioMore gain also lifts the player’s background hiss. Very sensitive IEMs can reveal it, whichever output you use.
General referenceGeneral referenceChoosing
Our customers
Share of player-plug choices on Null Audio cable orders over the last 24 months. Percentages only.
59.3%
Null AudioNull Audio orders, Oct 2024 – Oct 202629.0%
Null AudioNull Audio orders, Oct 2024 – Oct 20265.0%
Null AudioNull Audio orders, Oct 2024 – Oct 20263.4% (11.3% since 2019: the older Astell&Kern standard is fading)
Null AudioNull Audio orders, Oct 2024 – Oct 20262.8%
Null AudioNull Audio orders, Oct 2024 – Oct 2026Chosen on 12.6% of cables under USD 100, 48.0% at USD 100–200 and 65.0% on our flagships.
Null AudioNull Audio orders, Oct 2024 – Oct 2026Guides
Questions
No, the plugs are different sizes. Choose the plug for the output you use most, or Ethos Ultra, which comes with both plus a USB-C DAC plug.
Only because most players drive their balanced output harder. At the same volume setting the 4.4 mm output is usually louder; matched in level, the cable itself adds no loudness.
It gives more headroom and separate return wires per channel. Whether you hear a difference depends on your player and earphones; on several players the 3.5 mm output has the lower output impedance, which suits multi-driver IEMs.
It is the older Astell&Kern balanced standard. We still make it, but it is now chosen on 3.4% of our cable orders, against 29% for 4.4 mm.
Keep reading
Sources
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