Outboard preamp question

[drlndrve]

Question: if you have an outboard preamp, does it override your pickups? Ex) I have a Sadowsky outboard pre in chain with my Fender Jazz--why does it change the sound? I guess I'm wondering how they interact?

 

[line6man]

What do you mean by "override the pickups"?

 

[Frenchy-Lefty]

An outboard preamp is the same as an internal preamp, it amplifies the signal from your pickups, turn it to line level and often give you some control options. A little bit like a water pump in a pipe would accelerate the flow of water (which is the electric signal sent from your magnetic pickups)

The main difference is...it is not located inside your bass and your little fingers can't tweak it every 2 seconds. If you have monkey feet you can do the same tweaking-every-two-seconds thing with your feet playing with the knobs of your preamp pedal so then it is exactly the same thing. But I doubt you have monkey feet.

There is no "overriding" anything whatever it means (if you don't send any water into your water pump well there ain't no water to pump, right?)

It changes the sound because preamps are rarely transparent, meaning you don't hear the same sound as your passive bass but louder. Preamp designers like to "voice" their preamps so that the sound get a certain character with some frequencies accentuated or dimmed even when all the control are flats. The Sadowsky two band has a lot of character but some preamps like Audere are much more flat. Matter of taste that's it (Let's say your water pump could have a filter that filters all minerals before pumping, well some peeps love those little minerals and others just hate that rocky junk, right?)

Personally I like my basses to be passive for a bunch of good reasons I probably all made up in my mind after 30 years of playing the instrument.

 

[line6man]

An outboard preamp is the same as an internal preamp, it amplifies the signal from your pickups, turn it to line level

Not all preamps boost the signal. Many are unity-gain. And very rarely do preamps output a line level signal.

Note also that there is a major technical difference between onboard and outboard preamps. An outboard preamp requires the signal to travel through a length of instrument cable at a higher impedance than when the preamp is onboard. This leads to a loss of treble. Also, sometimes onboard preamps will be wired with lower value volume pots, placed post-buffering, whereas a passive bass fed into an outboard preamp will always have higher value volume pots placed before the buffering. This can alter the way the volume pot behaves, and the way that it interacts with the pickup coils.

 

[Snaxster]

Not all preamps boost the signal. Many are unity-gain. And very rarely do preamps output a line level signal.

Note also that there is a major technical difference between onboard and outboard preamps. An outboard preamp requires the signal to travel through a length of instrument cable at a higher impedance than when the preamp is onboard. This leads to a loss of treble. Also, sometimes onboard preamps will be wired with lower value volume pots, placed post-buffering, whereas a passive bass fed into an outboard preamp will always have higher value volume pots placed before the buffering. This can alter the way the volume pot behaves, and the way that it interacts with the pickup coils.

If you have monkey feet you can do the same tweaking-every-two-seconds thing with your feet playing with the knobs of your preamp pedal so then it is exactly the same thing. But I doubt you have monkey feet.

C'mon... you have to admit that this part was pretty good.

 

[drlndrve]

What do you mean by "override the pickups"?

I really appreciate your input, especially the difference between outboard and onboard preamps. I guess what I meant by 'overriding' the pups (poorly phrased) was, if you have specially 'voiced' pups, like my Select Jazz has--then I run it thru the Sadowsky pre--it loses its original sound and takes on the Sadowsky voice. Sorry for my bad phrasing--I have a real poor understanding of this. However, between yours and Frenchy-Lefty's post above, I'm getting it.

 

[drlndrve]

An outboard preamp is the same as an internal preamp, it amplifies the signal from your pickups, turn it to line level and often give you some control options. A little bit like a water pump in a pipe would accelerate the flow of water (which is the electric signal sent from your magnetic pickups)

The main difference is...it is not located inside your bass and your little fingers can't tweak it every 2 seconds. If you have monkey feet you can do the same tweaking-every-two-seconds thing with your feet playing with the knobs of your preamp pedal so then it is exactly the same thing. But I doubt you have monkey feet.

There is no "overriding" anything whatever it means (if you don't send any water into your water pump well there ain't no water to pump, right?)

It changes the sound because preamps are rarely transparent, meaning you don't hear the same sound as your passive bass but louder. Preamp designers like to "voice" their preamps so that the sound get a certain character with some frequencies accentuated or dimmed even when all the control are flats. The Sadowsky two band has a lot of character but some preamps like Audere are much more flat. Matter of taste that's it (Let's say your water pump could have a filter that filters all minerals before pumping, well some peeps love those little minerals and others just hate that rocky junk, right?)

Personally I like my basses to be passive for a bunch of good reasons I probably all made up in my mind after 30 years of playing the instrument.

Thanks for the explanation--that helped and made more sense to me than you know. Really appreciate it.