The OPA134 series are ultra-low distortion, low-noise operational amplifiers fully specified for audio applications. A true FET input stage is incorporated to provide superior sound quality and speed for exceptional audio performance. This, in combination with high output drive capability and excellent DC performance, allows for use in a wide variety of demanding applications. In addition, the OPA134 has a wide output swing, to within 1 V of the rails, allowing increased headroom and making it ideal for use in any audio circuit. The OPA134 SoundPlus audio operational amplifiers are easy to use and free from phase-inversion and the overload problems often found in common FET-input operational amplifiers. They can be operated from ±2.5-V to ±18-V power supplies. Input cascode circuitry provides excellent common-mode rejection and maintains low input bias current over its wide input voltage range, minimizing distortion. OPA134 series operational amplifiers are unity-gain stable and provide excellent dynamic behavior over a wide range of load conditions, including high load capacitance. The dual and quad versions feature completely independent circuitry for lowest crosstalk and freedom from interaction, even when overdriven or overloaded.