Fender Tone Stack With Different Bass Pot Wiring

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65greg
Posts: 20
Joined: Sat Dec 09, 2017 1:08 am

Fender Tone Stack With Different Bass Pot Wiring

Post by 65greg »

Hey All,

Working on some mods to a Crate VC3112

I have the lead channel sounding pretty good and now I'm on to the clean channel.

Looking to get some help understanding what the effect of wiring the bass pot differently will do.

I'm using the Duncan Tone Stack Calculator and looking at the Fender style circuit and comparing to a Crate Vintage Club 30 clean channel.

The Fender has the wiper of the bass pot tied to the node of the bass cap (C2 / 0.1uF on the Duncan calculator)

The Crate has the wiper of the bass pot tied to the node with the mid cap (C3 / 0.47uF)

https://www.thetubestore.com/lib/thetub ... ematic.pdf

Anyone know what difference this makes?

Thanks!

ps - here is a clip of the lead channel: https://www.youtube.com/watch?v=kajXD08Nt_g&t=8s
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roberto
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Location: Italy

Re: Fender Tone Stack With Different Bass Pot Wiring

Post by roberto »

Hi, it’s exactly the same in both circuits, you just need to check that the “cw” note and the wiper are connected to the same side. Being “just a rheostat”, it only matters that you get the log function as you turn the pot. You could even not connect the 3rd pin on the clockwise side, just the opposite one and the wiper.
65greg
Posts: 20
Joined: Sat Dec 09, 2017 1:08 am

Re: Fender Tone Stack With Different Bass Pot Wiring

Post by 65greg »

Thanks for the reply. I was thinking about it some more and yes, I see now its the same thing. I guess it was just the way it was drawn was confusing when I first looked at it.
pdf64
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Re: Fender Tone Stack With Different Bass Pot Wiring

Post by pdf64 »

Bear in mind that as a tone stack is effectively 3 RC filters wired in parallel, C2 is in series with each. Little effect on the treble C3 circuit, but the effective values of C4 and C5 will be reduced somewhat (being series circuits, it's immaterial that C2 is the 'other' side of the 100k slope resistor R4 to them).
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65greg
Posts: 20
Joined: Sat Dec 09, 2017 1:08 am

Re: Fender Tone Stack With Different Bass Pot Wiring

Post by 65greg »

Hey pdf64,
Thanks! Good catch that C2 is in series. I realized it was in series with C41 going to the other channel but missed the fact the tone stack caps are also.
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