active?

[ZPQ]

Hi,

Anyone care to chip in with an opinion on what I stand to gain by fitting a preamp to my Geddy Lee Jazz. (or why I shouldn't?)

It seems to me that the gain and eq on the amp can be adjusted to get the tones I want but perhaps there's an advantage I'm missing?

Cheers
John

[Lfalex]

[b]Pros:[/b]
There's greater tonal flexibility than passive.
The active EQ may cover different frequencies to your amp's EQ.
The active EQ may allow a greater Q (range of adjustment) than your amp's EQ.
The active EQ may be quieter than your amp's. Batteries deliver clean, isolated power.
You can use other rigs easily if you can get your sound from just the active EQ - Leave whatever amp you're using "flat".
You can get a shorter signal path if the above is true by bypassing the amp EQ. It may give you a punchier sound.
Similarly, if your sound comes form the bass, you can i) EQ the amp to compensate for the room acoustics
ii) Still maintain some degree of control over what the desk receives, even if a soundman inserts a DI box between your bass
and amp.
It'll probably run "hotter" than the passive incarnation, which may give you more drive if you want it.
If you don't like it, it's easy to remove from a Jazz and sell on...

[b]Cons:[/b]
Cost (of course), which varies according to what you want to buy. J-Retros are a popular choice.
Some EQs can smother the natural tone of the instrument (Some can enhance it, though)
Active EQs can reduce the immediacy of the sound against the passive version of events.
Will it fit without routing the control cavity to a greater depth?
Will the cavity need shielding/more shielding to keep noise gremlins at bay?
You may lose the 2 volume controls in favour of 1 volume, 1 pan. Can you tolerate that. You may find it better as you can "fade" the bass in a live environment.
Could an outboard pre (Sadowsky, Aguilar etc. etc.) do the same for you without the mods to the instrument?
Batteries can die mid gig, which can be a pain. A true passive bypass is a good idea!

That's about all I can think of!

[Brother Jones]

Just one pedantic addtion to the pros - active will enable you to run a greater length of cable on stage without signal degredation (mainly loss of high frequency info).

I play an active Sadowsky MV70 Jazz, but also just bought a passive (a CIJ reissue) and am liking it a lot.

[dirtystatic]

good post from Lfalex there. you could run into more problems if you use FX pedals as some don't get on too well with active basses.