Do different pre-amps produce different sounds!?

[Anon2962]

I have rently ordered the 'realist' pick up, and have decided to get a pre amp. i have never used a preamp before. I hear good things about K&K, and saw that they can be fitted to the tailpiece (bob gollihur), which looks nifty. But do different preamps have different sounds?

I play a nice old german carved bass, and use a swr workingmans 15"amp.

Any advice please?

[AMJBASS]

You won't need a preamp with the Realist. It usually sounds just great going straight into the amp.

[Anon2962]

Oh really? I heard of some people having problems without a preamp, but i'll give it a go without, thanks adrian.

[Chris Fitzgerald]

Can't completely agree with Adrian on this one. First, I don't think the Realist sounds great at all, but that's a subjective thing. Otherwise, I think that preamps can be useful if the sound of the pickup has aspects that you don't care for - when this happens, a preamp can help to tame those things you might not like. I would advise seeing how you feel about the pickup, then trying a preamp if you think the signal is unbalanced one way or another.

[bucephylus]

My experience is that pre-amps matter a lot both in terms of tone and feedback. I have had the best luck using an ART MP-1 microphone pre-amp. It has a 12AX7 tube in it, which adds considerable depth to the tone. If you get really deeply into this sort of stuff, you may find the 5751 form of the 12AX7 has a little more depth. The MP-1 is mainly a leveling pre-amp; so, it does a good job matching impedance and minimizing feedback. Also, it's pretty cheap.

- pt

[AMJBASS]

You're right Chris. A preamp is great for tweaking the sound. I am not particularly fond of the Realist either, but IME it works just fine right into the amplifier. I think the Full Circle is an big improvement on it.

[jstiel]

Originally Posted by bucephylus

The MP-1 is mainly a leveling pre-amp; so, it does a good job matching impedance and minimizing feedback
- pt

How does this match the impedance? The spec sheet says the input impedance is 840k ohm. I thought that a piezo pickup needs at least a 1M ohm input.

[Marc Piane]

I use a Realist with a K&K Golden Trinity upgrade into a Sansamp Bass Driver (preamp) into a SWR WM12. I find the output of the Realist to be a bit low. A preamp helps this and seems to liven things up a bit. I have been very happy with the tone. It is a little on the dark side, but that is the sound that the Realist produces. If you don't like that sound, try a different pickup, no preamp will help.

[fdeck]

Originally Posted by jstiel

How does this match the impedance? The spec sheet says the input impedance is 840k ohm. I thought that a piezo pickup needs at least a 1M ohm input.

For all practical purposes, 840k = 1M. In theory, increasing the input impedance beyond this point can improve your signal to noise ratio, though I have never measured the results on an actual pickup.

The term "matching" is a bit of a misnomer, relating primarily to radio-frequency and digital transmission lines where the exact match is important. With a piezo pickup, what really matters is simply raising the input impedance above the point where the impedance affects your tone. Typically this is in the ballpark of a Megohm. Signal to noise is a secondary issue.