by cockroach » 11 Oct 2009, 10:23
True, but surely the reason why amp makers started providing effects loops built into amps is to avoid the problem of effects units (with higher input signal due to the boost from the usual battery or mains powered pre-amps built into most , if not all, effects units) overloading the guitar amp input and the amp's actual pre-amp unit and causing unwanted distortion?
This may have given unique sounds to guitarists in the past, but it really didn't do the amp much good. Did I not read that Hank's Q20 was turned up too much by his guitar tech, causing distortion of his sound on parts of the Final tour DVD? Remember, you have three or four separate gain/volume controls to juggle- guitar, effects and amp...to get the correct levels for each.
If you go to all the trouble to get 'that sound' or some magic tone from your amp, then plugging the guitar into the effects unit then plugging straight into the amp input will affect and change that sound...
If your amp has an effects loop, then you may as well use it. The amp pre-amp then gives the required tone, the looped effects unit gives the effect desired to be applied (echo, chorus etc) then the guitar power amp provides the final signal to the speakers at the level required. This is using a modern guitar amp as it was designed to be used.