My humble apology if I have asked a similar question in the past...I checked my history and couldn't find anything. Anyways here goes. I appreciate any/all help. I have a Spector Performance series 4 string that is passive. I am in the process of refin'ing it and I am going to make it an active bass by adding a preamp into the control cavity. It is currently set up with two EMG-SSD humbuckers and 4 knobs (1 tone and 1 volume for each pickup). I would like to find a good preamp that I can use with these pickups and also would give me the ability to install a small two-way switch for passive/active operation. Any ideas on models of pre-amps I should be looking at?