Op-amp swapping is the process of replacing an operational amplifier in audio equipment with a different one, in an attempt to improve performance or change the perceived sound quality.
Operational amplifiers (op-amps) are used in most audio devices available, and as such it not uncommon for them to be a target for replacement by DIY enthusiasts. Also, the replacement is fairly simple, which also contributes to its popularity. This requires the desoldering of the old IC and it's replacement with a new one. An IC socket can, and is commonly used to prevent repeated soldering in cases where more than one swap is desired. Some devices are manufactured with sockets for their op-amps[1] and are advertised as a feature.
Although replacing op-amps may be simple, proper design needs to take into account the new device's parameters, which is not done in a simple swap. This has led to a number of problems occurring, most common being high frequency oscillation.[2]