Double Bass Impedance matching preamp placement in signal chain

[steve.whipple]

Hello!

Long time lurker, first time poster here...

I understand the importance of having an impedance matching preamp before sending a signal to an amp or the house, but am I correct that it has to be the first thing the bass plugs into? Or will you still get its full benefit if it go into a tuner or a mute switch first?

I tour with a band that owns most of the gear. But they don't have an impedance matching DI, so it's never sounded great in the house, to my ear. I'm considering bringing either my fDeck or my Acoustic Image Flex preamp on an upcoming tour to add to the signal chain. The gig is a doubling gig, so they have two tuners that double as mute switches when I go between instruments. So my question is, should the upright (it's a TravelBass with either a Full Circle or Realist Lifeline) be plugged into the preamp before the tuner for maximum benefit, or does it not make much of a difference?

Thanks!

 

[Wasnex]

Hello!

Long time lurker, first time poster here...

I understand the importance of having an impedance matching preamp before sending a signal to an amp or the house, but am I correct that it has to be the first thing the bass plugs into? Or will you still get its full benefit if it go into a tuner or a mute switch first?

I tour with a band that owns most of the gear. But they don't have an impedance matching DI, so it's never sounded great in the house, to my ear. I'm considering bringing either my fDeck or my Acoustic Image Flex preamp on an upcoming tour to add to the signal chain. The gig is a doubling gig, so they have two tuners that double as mute switches when I go between instruments. So my question is, should the upright (it's a TravelBass with either a Full Circle or Realist Lifeline) be plugged into the preamp before the tuner for maximum benefit, or does it not make much of a difference?

Thanks!

Plug the pickup directly into your high impedance buffer device.

 

[Ludwig]

The impedance matching between a piezo and a high impedance preamp works only, if the piezo is connected directly to it. If you have another device in between with lower input impedance, the piezo does only see that and the mismatch already happend. The cable between a piezo and a high impedance preamp should be as short and high quality as possible as well to have best sound result.

 

[DoubleMIDI]

It can work with some tuners and mute switches, but that depends on these deceives.
Short cables are best, the shorter the cable the less important the high quality of it, but it should not be cheaply made.
If you want to have local access to any controls (HPF, volume) on the preamp, you might want to mount it on the tailpiece (if possible). So that way you naturally get the impedance buffer/preamp first after the piezo which is the best you can do.

 

[steve.whipple]

Thanks for the comments everyone, very helpful!

 

[Ric Vice]

So at least for me, having a full preamp, with a built in piezo buffer section makes the most sense. This was my reason for moving to the Headway EDB 3 H E and the Grace Designs Felix
and using a powered cabinet. Of course there are other ways to accomplish this. The simplest is to find an amplifier that's the best choice for a piezo pickup al la Acoustic Image, Euphonic Audio, Walter Woods,
or a host of other amps with 1 Meg Ohm input impedances and match that with a pickup that responds favorably to that impedance, like the Realist or Full Circle. If you own an amp you really like, then
get a buffer preamp like the ones mentioned above.