AudioChainsDB
Sennheiser

HD 660S2

headphones

$480

Used market: $375*

Find at ThomannManufacturer datasheet

Specifications

2 of 7 values have a recorded source
Connector
6.35 mm + 4.4 mm balanced·
Form Factor
Over-Ear·
Is Closed Back
no·
Impedance ohms
300✓
Transducer Type
Dynamic·
Detachable Cable
yes·
Sensitivity dB V
104✓

Expert Audio Engineering Commentary

Tonal Profile

The S2 went back to 300 Ω after the 150 Ω HD 660S — the two are one digit apart in the name and a factor of two apart in the current they draw. Check which one you actually own before trusting any amplifier calculation.

* Estimated with the depreciation fallback (~78% retained value). · checked on 8/5/2026