What Bart pre is this? How to make 18v?

[ledyard]

I checked my bartolini pre last night finally to try and determine what it is. Theres no markings or labeling on it of any kind.
The problem I posted about before was that the pups were too quiet. But I loved the sound. There is also no tiny pot on the pre anywhere to turn the gain up as also suggested. Someone suggested changing the pre to 18v. So before I gut this thing and change everything I was wondering:
1) does anyone have a clue what model Bart pre this is?
2) how do I make it 18v?

[12bass]

Doesn't look like a Bartolini preamp.... most of their stuff is potted and looks like this:



Chances are good that whatever that is, it will work at 18V. But definitely check the specifications on the op amp and capacitors before proceeding.

[ledyard]

Originally Posted by 12bass

Doesn't look like a Bartolini preamp.... most of their stuff is potted and looks like this:



Chances are good that whatever that is, it will work at 18V. But definitely check the specifications on the op amp and capacitors before proceeding.

Yeah I was kinda thinking that it didnt look like one. I remember looking in my Pedulla and it was like your pic. Also in another old Fender I had long ago it looked the same way.
Well, most likely this thing isnt a Bart Pre then.
I wonder what the **** it is?

What exactly am i checking for? As far as that goes I completely ignorant.

I do think I will rip it out though and get an Aguilar or something with alot more snot.

Anyone have any suggestions for a Pre that has alot of balls but is fairly transparent as to let the natural pup sound shine through.

[Rob22315]

Well, if you are really looking for just the natural sound of the p'ups . . .

I'm new to the art of preamping basses but for fun, I built my own preamp based on designs here on the internet to go along with the p'up upgrade to a used GSR200 I got off craigslist. I built one of the infamous JFET preamp/buffer circuits. The circuit board is about the size of a postage stamp, is powered by a 9v battery, and there are no tone controls, only a single JFET buffer. I get about 6dB (guessed, not measured) gain out of it and probably could get more if I upped the drain resistor a little bit. I kept all the original passive controls - V/V/T. This preamp really didn't color the sound of the dimarzio's at all compared to passive, just made them louder and eliminated any tone coloring due to changing cable impedance.

Costs about $10 for the parts and a little soldering time if you're willing to go back to an almost passive setup. It would be easy enough to add any kind of tone control (2 or 3 band active or tone stack) or tweak the design for 18V if you wanted. There's lots of good info on the net and parts are cheap. I would have done these upgrades to my preamp but I decided to upgrade the whole bass to a BTB675.

[DanScott]

I do know that I originally put a Ken Smith pre in this bass, I'm guessing it is still in there, but it was a long time ago..

[line6man]

Running 18V shouldn't increase the gain, only the headroom.

In any case, you simply put two batteries in series to run a preamp at 18V. Make sure it's designed to handle 18V, first.

[BigOldHarry]

Agreed. If that's a Bart, it's an old one.

I don't see the point of 18v preamps. I had one, it just mean I had to use more batteries (and they wore out more frequently).