In regards to changing out the pickups, I own 2 Spectors, and what I ended up doing was actually asking the guys at
www.spectorbass.com what I need to do and one guy offered a suggestion and directed me to the pickups at the EMG website, told me how to install them and even sent me a PDF file with detailed instructions. That's service for ya =)
I went from passive to active, but this was an older model bass before they made the Tone Pump Jr. stuff, so I don't really know what to tell ya with that thing. I'm just trying to say that Spector's customer support may be able to offer the best advice
I know it seems like an ass thing to just put throw a link at you, but it's the best way for me to answer the question regarding active versus passive
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