What’s The Difference Between Active & Passive?
So first of all, what’s the difference between passive and active basses? Well, It’s all to do with the pickups or more accurately the electronics and preamp that work alongside the pickups.
A Passive bass is a normal, run of the mill bass with a basic single tone control. The term active bass usually refers to the addition of a preamp, the same as the one in your amp and this preamp is powered by a battery. So think Active is powered, Passive is not.
Most active basses have passive pickups with active circuits. But some basses do have actual active pickups like those made by EMG. In those cases you’re looking at pickups that are battery powered rather than the preamp. So it’s important to make this distinction. However, for the most part, when you’re shopping around for a new instrument, the term active bass will refer to the active preamp in there not the pickups.
How Pickups Work
All basses have a set of pickups that create an electrical signal from the plucking of the strings. I won’t bore you with the more intricate details of how that happens here, just check out Faraday’s Law Of Induction and then google ‘How Pickups Work’ and it should all make a little more sense.
Basically we get a voltage from the movement of the strings through a magnetic field. If you’ve ever taken the case off your pickups you’ll see the copper wire around a magnet. That’s our magnetic field. Pluck the string, it moves through that field. Hey presto. Electricity.
On a regular passive bass, the electrical current from our pickups passes through a single tone control, volume control and out through the lead to an amp.
The important thing to realise here is that the tone control is just a simple resistor acting on that current we’ve created. So we can only take away from the signal, we can’t add anything to it. Boosting would mean bringing extra power in from somewhere. The tone control on a passive bass can only cut. It can’t boost.
On an active bass that electrical signal comes out of our pickups in the same way but then runs into a powered pre-amplifier.
This allows us to have all kinds of tone controls like we would on a regular bass amp. This is simply because we’re supplying more electric into the mix from the battery. Instead of cutting the tone like on a passive bass, we can boost any frequency.
This means we can have a bass control, treble control, mid control and even parametric mid controls where you select the frequency required. Anything you might have on a bass amp can be fitted on the bass itself. That’s all it is. We’re taking the features of a preamp and putting them on the bass so it’s all right there at the fingerttips.
Most active basses will have a bypass switch so you can go between the direct passive signal and the affected active signal. If you set everything flat on your tone controls you’ll pretty much have the same sound. The main difference will be your level. Because an active circuit is powered, you’ll get more output in active mode. But in terms of tone, it’s just a case of having more options right there on the bass.
In the case of active pickups, like the EMG’s mentioned earlier, the pickups themselves have to be powered. The pickups are wound to have less output which is then boosted via the battery. It’s often said this results in low noise and a more Hi Fi kind of tone. Some players love them, it all depends what you’re going for.
Passive Vs Active
So this brings us to the big question. Which is better? Passive or Active?
Well, as you’ve probably already guessed, the answer is neither. It all depends on what you want from the instrument. Regular passive instruments are great. If you just want a bass you can pick up and play with no extra bells and whistles then go passive.
In deciding whether to go active or not you have to look at the pros and cons. Active basses require a battery so that’s you’re first issue right there.
As the battery starts to die you start to get multiple issues in the sound. Your level starts to drop, the tone starts to thin out and eventually distortion starts to creep in before it’s final last gasp.
If you’re on stage as this starts to happen, all kinds of things can go through your mind because you might not initially realise it’s the battery. You can start looking to every bit of your other gear for problems because a lot of the symptoms are similar to issues you might get from a bad lead or a faulty amp.
Luckily most actives have a bypass switch so you can get around it that way, but it’s still something a lot of players don’t want to ever deal with.
As for the pros of going active, it’s all about choice. You can adjust your tone right there on stage, on the fly without having to go over to the amp. Setting up your tone at source also helps if you’re going direct to the mixer pre-eq or before your amp.
Another pro for some is the preamp buffering and added output level. This can help with retaining your sound on long cable runs and gives you more signal to play with in a variety of different inputs on amps and recording equipment.
However, this additional output level is also another con for some people in that it can be too much level for some effects pedals. Some pedals just don’t play nice with active basses.
As I said, it’s all about your needs as a player. Don’t just think “Oh I need an active bass because I hear they’re better!”
That’s not the case at all. If you want to go for a more traditional kind of sound, then you can’t do better than grabbing a passive p bass or jazz. No need for active circuits. No need for tons of tone shaping. They are what they are. The lack of variables in there can make everything a lot more straightforward.
But if you want that extra tone shaping on the bass itself and some additional output level then Active basses are the way to go.