Low Z: too low?

[Biarnel]

Hi again,

..as an experiment I tried winding two 5-string bass coils, wired in humbucking fashion, with 5 (10mm dia.) alnico mags per coil.
I wanted something tifferent to test, so I give 1600 turns each coil: now I have two 1.5kOhm each coil, 3k when in series.

The output is obviously too low, and I need a premp.
Any suggestion? A simple Artec 3-way preamp for bass?
I have a K&K external preamp, but the sound is too low in volume even at max values.
Maybe a mosfet (or fet, I don't remember) buffer will be necessary? I mean, one of those things like..

[David Schwab]

The reason is that is a buffer, but it doesn't add any gain.

Try this one:

Alembic Stratoblaster Schematic

Remove the 68K resistor at the beginning, and use a larger output cap, something like 5 or 10uF.

You may need to turn the gain all the way up, but that's to be expected, and it works fine.

I wind pickups with impedance as you are doing, and a circuit similar to this works great. They get very loud and clear.

[Louie Seven]

not TRYING to highjack the thread.... but DAVE, can you address this issue for me....

With our discussion of the Lp Recording Guitar pickups in mind view -

I have two generic ordinary Gibson type (guitar) humbuckers that I bought cheap.

My plan is to tear them down and rewind them with 29awg, using aLnIcO V bar magnets that I purchased from AllParts.

Other than the wire and the winding count, I'm not changing anything else. This is basically a test and/or an experiment. I elected NOT to go with stacked coil because of mounting issues. I want to put these on a Les Paul that's routed for normal hummers.

What do YOU think the results might be, sound wise?
Any practical issues I'm overlooking?

Thanks,

Louie

[Joe Gwinn]

Hi again,

..as an experiment I tried winding two 5-string bass coils, wired in humbucking fashion, with 5 (10mm dia.) alnico mags per coil.
I wanted something tifferent to test, so I give 1600 turns each coil: now I have two 1.5kOhm each coil, 3k when in series.

The output is obviously too low, and I need a premp.
Any suggestion? A simple Artec 3-way preamp for bass?
I have a K&K external preamp, but the sound is too low in volume even at max values.
Maybe a mosfet (or fet, I don't remember) buffer will be necessary? I mean, one of those things like..

How much gain do you need? The circuit as shown has a voltage gain of about three (9.5dB).

Stick with the BF245 JFET - they are far quieter than MOSFETs.

You may need a 47K resistor in series with the input to prevent punch-through on peaks.