Of all the basses that I wish would be re-issued, the G&L El Toro would be my #1. During my time at G&L
I was only ever given one chance to dig into a vintage unit. This is when I drew out this diagram......
I also drew up a schematic of the circuit board that I was looking at. Here it is.
In a previous post, I talked about ways to Tame the L-1500/Climax bass. While there are some similarities
between the the El Toro and these other two basses, the Taming process will be a bit different.
If you look at the schematic diagram you will see a .001uf capacitor connected to the clockwise (CW)
lug of the Treble control (the dot indicates the clockwise position). The center lug of the Treble control
connects to ground and the .047uf Treble cap connects to the counter clock wise (CCW) lug.
So.....here's what happens when you turn the Treble control. When the Treble control if fully
CW (Brightest sound) you have the .047uf Treble cap isolated from ground by the value of the
Treble pot (250K ohms). At the same time, you have the .001uf Treble boosting cap from the preamp
going directly to ground, giving the preamp it's maximum gain at high frequencies. So what happens
when we turn the Treble control in the opposite(CCW) direction? Well, the .047uf Treble cap is now
connected directly to ground which darkens the pickups a lot. At the same time you have the .001uf
Treble boosting cap from the preamp going through the entire value of the Treble pot (250K ohms)
before going to ground, which reduces it's treble boosting ability to almost nothing.
Now, lets say we want to soften the brightness of the preamp when the Treble control is at fully
CW position. The easiest way to do this is to increase the resistance in the connection to the
Treble control that comes from the preamp. If you look at the wiring diagram, you will see a yellow wire
that comes off the preamp board and connects to the CW lug of the Treble control. if you lift the
yellow wire off the control and connect a resistor between the yellow wire and the control lug
that the yellow wire used to be connected to, you have now increased the resistance that the .001uf cap
sees to ground which reduces the preamps treble boosting ability. What value of resistor you ask?
Depends on how much treble boosting you want to remove. You could start with something like 10K
and see how it sounds. The larger the resistor value the lower the treble boosting will be.
If you didn't want any treble boosting from the preamp you could just remove the yellow wire all together.
This resistance we are talking about could be compared to the "R7" mods of the L-series basses.......kind of.
One other interesting thing about the El Toro bass is that it has one of the largest pickup loading caps
that G&L has ever used. This cap is located on the back of the Bass control. Its the one that is connected
from the Bass control center lug and ground. The value is a .0022uf. If this cap is missing,
you will have a very bright sounding bass. If it's there and you want to deepen the bass a bit,
you can solder a .001uf cap in parallel with it. Anyway, just something to experiment with.
I hope this adds a bit of helpful info on the El Toro. Keep us all posted on your mods.
I really wish I had one of these basses.
Paul
Admin note: Click the images for a PDF version.