HELP ....SOMEONE HAVE THE ampeg AUB-1 PICKUP DIAGRAM/SCHEMS ????

[mauroconga]

HI ....
A friend have a AUB-1 ampeg bass ,but the "mistery pickup" not works ,and he not are capable to disarm this...
someone have some images from this pickup ? ..or a link of the patent, or any diagram to repair this ..?

[soundguruman]

The pickup I think is piezoelectric, not magnetic:
Piezoelectric Transducers
For some help, contact:
Bruce Johnson of Johnson's Extremely Strange Musical Instrument Co., 119 W. Linden Ave, Burbank, CA 91502; (818) 955-8152.

[David Schwab]

The pickup I think is piezoelectric, not magnetic:
Piezoelectric Transducers
For some help, contact:
Bruce Johnson of Johnson's Extremely Strange Musical Instrument Co., 119 W. Linden Ave, Burbank, CA 91502; (818) 955-8152.

No, it's magnetic. It used a spring steel disk under the bridge with magnets that move in the pickup coils.

Bruce Johnson has talked about that here and even posted some photos.

Some relevant threads:

http://music-electronics-forum.com/t15992/

Bruce said in this thread:

The "mystery" pickup in Ampeg's horizontal Scroll Basses (AEB-1 & AUB-1; 1966-1968) uses a single diaphragm. It's about 5" (127mm) square, and has an effective diameter of 4 3/4" (120mm). It's made of 2 layers of 0.030" spring steel.

On your magnet and coil designs, just don't go too far trying to make them powerful. If you create too large of a signal level, the amp is going to clip and distort. And to properly load the amp, the coils should have a resistance in the range of 5K to 10K ohms.

Just to give you a reference point, the system in my AUB-2 Scroll Basses has two coils with a total of 10K ohms resistance, and two 1/4" x 3/4" Alnico V magnets that move within the coils. That gives plenty of signal level in a passive circuit. So, don't go crazy adding magnets! I really doubt that you'll need the stationary magnets that you have shown in your drawings. The moving magnets, particularly neo's, should have all the field strength that you need.

http://music-electronics-forum.com/t10435/