IMO, while the A-C pre is simply amazing with the LM models (70's ash/maple), I never used the preamp on the LG I had... sounded better passive IMO, if you were actually going for the more traditional 60's J sort of thing.
Never bypassed the pre with the LM, never engaged it with the LG.
Makes sense really. Seeing as I'm chasing a 'vintage jazz' type of tone rather than a Marcus like modern 'jazz on steroids' sort of thing. Whatever gets me that low growl will make me happy!.
Cheers
Ben
Been in TX for 18 years now.. Still have the NY thing going on.. .. I do say YALL though.. HA