Originally posted by @Charlie Tuna in response to his questions about the Redstone EQ.
"Yep you've got the idea right. The tonestack is modified using the Fender tonestack as a starting point.
In the case of the Redstone, the Mid control is centered at 600Hz. When all 3 tone controls are at noon, there is an 8db dip from the Lows, and Highs to the mid scoop. When Mids are at max, with Highs and Lows at noon, the dip is more like 4dB. Turning Mid to minimum, with Highs and Lows at noon, the dip is huge at 15dB-ish.
To get ruler-flat response you would lower Highs and Lows to minimum. When this happens, the Mid control can be set anywhere, as it simply acts like another gain control.
With Mid, Low and High at noon, the Highs reach the peak amplitude at 10kHz, and from there gently slope downward toward the mid dip. At 2kHz they are roughly 3dB below peak. Lows reach peak amplitude at 40Hz, and slope gently downward towards the mid dip, 200Hz is roughly 3dB below peak.
Obviously, these numbers deviate as you manipulate the controls. The Redstone has great bass. I was really focusing on getting it sounding good with bass. I brought prototypes to my band's practices and based much of the tonal choices on feedback from my bass player. For reference, he mostly plays a vintage G&L L5000. So I know the Redstone can even handle 5 string basses pretty well. Other basses used in the process: my 1980 G&L L1000, an American Jazz Bass with '62 wiring, and a Peavey T40 with an aluminum neck.
It was a bit of a balancing act to make sure the Redstone sounded good with both bass and guitar. For example, I think the ideal bass high-end, would be a little different. It's also possible that some folks would want the the center mid-dip frequency a little lower for bass guitars. It also has probably more bottom-end than most guitar players need!
So the compromise I chose was to get great bass for bassists, decent all-around mid-band response that's less scoopy that a stock Fender, and highs biased towards guitar players. I think we did pretty good, hopefully you dig it!”