The Classic
the evergreen classics
So once upon a time I was a proud and happy owner of a mexican made Fender Jazz Bass. It had that classic sunburst look with a tortoise pickguard. Unfortunately I had to sell it for economic reasons, but ever since that I've had this itch to make a Jazz copy of my own, with that classic sunburst finish.
As always, I started building two builds at the same time, this "The Classic" and "Red Red Wine". One of my best sounding basses I've ever built had a body made of aspen. To keep it on the classic side I chose maple for the neck and wenge for the fretboard.
Of course this bass needed jazz bass style pickups, and I remember seeing some cheap and chearful ones with alnico 5 magnets on a domestic webshop, from which I had previously bought a lot of parts for my build.
The bass builds I've done over the years had always been 34 or 32inch scale lengths, so I had been wondering (for a while) what a 33" bass would feel, sound and play like?
Time to lay down some specs;
| Construction: 4-string
(bolt-on) Scale Length: 840mm (33") Strings: Dunlop 45-105 Number of frets: 24 Tuners: Gotoh GB707 (Chrome) Bridge: Gotoh style (Chrome) Frets: Sintoms Medium Jumbo |
Neck wood: Maple, Merbau
(5-piece) Body wood: Aspen, figured birch top. Fretboard wood: Wenge Neck pickup: OL JB Bridge pickup: OL JB |
Working on "The Seven Seas" I had made some research and testing on my DIY preamps. However, the previous preamps used a op-amp with a fairly normal power consumption of 8-10mA's. This much power drain in a onboard preamp powered by a singel 9V battery would drain the battery fairly quickly. The average capasity of a 9V battery is about 500mAh, and with a circuit power drain of 8mA's, you get about 40 hours of power. Sounds like a lot, but it really isn't.
So I measured some of my factory made onboard preamps that I have, and it turned out the power consumption on those is only about 0,4mA's. That's 95% less than 8mA's!
So I had to do some research to find a dual op-amp with very little power consumption, which fortunately turn out to be quite easy. The OPA2137 is a dual FET input op-amp with a very low quiescent current of 0,22mA per amplifier. So I soldered the complete circuit together and measured 0,87mA's. That's more like it, now the battery capasity was increased to about 400 hours.
Since there really wasn't any space for a additional mid pot, I got the idea to replace the mid pot with a switch instead which would be placed in between the bass and treble pot. All that was needed was a SPST on-on-on switch and two 50k resistors. So the switch now worked as a mid-cut/flat/mid-boost switch. And while I was at it modifying the electronics I also decided to add a low battery warning LED circuit, just as I did on "The Seven Seas". So this is the layout I ended up with.
This bass was sold in 2019.