Topmusicanswers
An FX Loop is essential an insert point in your amplifier circuit that allows you to insert a piece of gear after the preamp circuit, but before the power amp circuit. Some guitar players are happy to run everything into the front end of the amp, and others prefer to insert certain effects types into the loop.
What is the purpose of an FX loop?
An effects loop is an input/output that allows you to place effects between the pre-amp section of the guitar - where it gets its tone and the power section of the amplifier - where it amplifies the sound. This means that your pre-amp can go anywhere in the signal chain rather than having to be the last stop.
What is external FX loop?
A signal path out of one piece of gear, through an effects unit, and back into the first device. ... In most cases they work just like the insert of a mixer: plugging something in breaks the internal signal routing to send the signal through the external loop.
