Check the listing for details. Single Discrete Audio Op Amp SS3601. Condition: New. Listed at 39.00 USD. Sparko's Labs has created a family of discrete op amps in an 8 pin DIP compatible package optimized for high performance audio applications. These devices are drop in replacements for many common, yet inferior audio op amps and are uniquely compensated for trouble-free swap out into virtually any circuit. Having a footprint of a mere 0.33 square inches, these devices are one-third the size of any other discrete op amp on the market. Class A biasing and high output current capability coupled with a two pole compensation scheme requiring multiple NPO dielectric capacitors make these discrete op amps impossible to fabricate as a monolithic IC. These devices utilize matched transistor pairs encapsulated within a single device package for the input stage and internal current mirrors, which retains the advantage that monolithics have with device matching. Installing these devices in place of ordinary IC op amps in your audio system will yield vast performance improvements ranging from quieter or "blacker" background due to their low noise performance, and more detailed, crystal clear highs due to their high loop gain and two pole compensation. For product reviews, see : http://sparkoslabs.com/discrete-op-amps/reviews/ If you are willing to write a review and / or take some pictures of these devices in your audio system, I will accept reasonable offers below list price. SS3601 Single Discrete Op Amp Data Sheet All Devices Include +/- 15 mA Class A output current+/- 40 mA Class AB output current+/- 6V to +/- 18V supply voltage rangeSingle or Split supply operation is possible3 nV/√Hz typical noise performanceSmallest discrete op amp on the market – 0.33 Sq. In.True op amp requiring no flying groundUniquely compensated for trouble-free drop-in into any circuitExtremely tolerant of capacitive loads and high feedback network impedanceFully discrete design Applications: Audio MixersDAC circuitsCompressor Circuits Audio Pre-AmpsLine Drivers / ReceiversMIC AmplifierRIAA AmplifierTone Control CircuitryAudio EqualizersAnywhere That An Op Amp Is Required!