active pickups??

[Angel]

having built 5 electric guitars now I thought I'd have a go at making a bass. The thing is, I know a fair bit about guitars, I don't know much about basses. I like modern bass sounds so I was thinking of trying to get some active pickups, but I'm a bit lost with knowing what one needs. With active pickups does one also need to be getting some sort of preamp? 

Could you get passive pickups and add an active preamp?

 

Edited May 19, 2020 by Angel

[TrevorR]

39 minutes ago, Angel said:

Could you get passive pickups and add an active preamp?

That’s by far the most common way of doing active basses... PICKUPS which are active themselves are actually pretty unusual.

Lots of decent quality passive pickups out there at different price points. Active circuits to check out include John East, Aguilar, Audere (my personal fave),  Darkglass, Seymour Duncan... and many others.

[itu]

pickups - blend - vol - tone - output

Any part in this signal chain can be "active" (battery powered, that is; low impedance = lo-Z to be correct). The most common way to "activate" an instrument is to add a battery powered tone capsule that can boost certain frequencies (most common are B/T). High impedance circuits (hi-Z, "passive" tone) can only cut.

EMG has pickups with internal buffers. They can be considered "active", but the main point is that their output is lo-Z. Lo-Z output is less prone to interference and the cable length does not deteriorate the signal so much. For the hi-Z signal maybe 30 feet/10 m is still doable, but lo-Z signal can pass even 300 feet/100 m cable lengths.

OK, if any part of the signal chain is lo-Z (to simplify things: battery powered), the output becomes lo-Z. The least common parts in the chain are active blend and vol. There are only few companies that offer active mixing like Audere, EMG, John East, and Noll. That £300 Sadowsky is only a tone circuit, if not pretty nice sounding.

Why bother having an active mixing? Well, the biggest issue is, that any hi-Z component directly in the signal chain does two things: reduces volume and frequency response. Guitarists tend to use bleeding capacitors in the (hi-Z) pots to lessen the higher frequency reduction. If the "active" circuitry is only after the blend and vol, these first two pots affect the sound, like it or not.

[Angel]

Thanks for the replies.