The dual-channel OPA1678-Q1 and quad-channel OPA1679-Q1 (OPA167x-Q1) operational amplifiers offer higher system-level performance over legacy op amps commonly used in audio circuitry. The OPA167x-Q1 amplifiers achieve a low 4.5-nV/√Hz noise density and low distortion of 0.0001% at 1 kHz, which improves audio signal fidelity. These devices also offer rail-to-rail output swing to within 800 mV with a 2-kΩ load, which increases headroom and maximizes dynamic range. To accommodate the power-supply constraints of many types of audio products, the OPA167x-Q1 operate over a very wide supply range of ±2.25 V to ±18 V (or 4.5 V to 36 V) on only 2 mA of supply current. These op amps are unity-gain stable and have excellent dynamic behavior over a wide range of load conditions allowing the OPA167x-Q1 to be used in many audio circuits. The OPA167x-Q1 temperature ranges are specified from –40°C to +125°C.