1. Some effects units operate at +4 dBu, some operate at 0 dBu, and some operate at -10 dBu. Most foot pedals operate at -10 dBu, and most pro gear (rack effects) operate at +4 dBu. An effects loop allows the use of pro gear, especially for reverb, delay, etc.
2. Some people prefer to have the sound of the preamp processed before some effects, especially if using the amp's overdrive/distortion.
The only real use for an effects loop is for time-based effects, like chorus, delay, reverb, etc.
...and if you don't like it, you can suck on an egg.
Comments
1. Some effects units operate at +4 dBu, some operate at 0 dBu, and some operate at -10 dBu. Most foot pedals operate at -10 dBu, and most pro gear (rack effects) operate at +4 dBu. An effects loop allows the use of pro gear, especially for reverb, delay, etc.
2. Some people prefer to have the sound of the preamp processed before some effects, especially if using the amp's overdrive/distortion.
The only real use for an effects loop is for time-based effects, like chorus, delay, reverb, etc.