Fulltone 69 Contour Setting

[Mcentee2]

I have had a FT 69 Mark II for some time and have never really truly got to grips with the contour setting, so I thought I would dust off the Geofex and Electrosmash articles as well as countless DIYStompbox threads to once again familiarize myself with the FF stock circuit.

Anyway, on reading the 69 manual it distinctly says (my Bold Underline):

"Contour: This very effective knob adds Midrange clarity and overall gain when turned
clockwise, and is out of the circuit and stock Fuzzface-style at full counter-clockwise"

The circuit, not just the internet schematics, and verified by me opening the pedal and looking and measuring what goes in/out of that pot, is of course that the following resistor before the Q2 bias trim is 220r.

Now, everywhere I have seen re the FF circuit, for Ge at any rate, that resistor is nearly always 470r, so I can't get round the FT manual above that putting the Contour fully CCW and out of circuit results in a "stock" FF ?

I know that Si FF reduces it to a standard 330r, and other designs change it around, so reducing it even further surely reduces Q2 and overall Gain even further ?

I can't spot any other resistors in the line that would add onto the 220r to take it to 470r.

So to me the FT 69 "stock" FF would be with the Contour at 11 o'clock (measured off the pot).

I know the standard answer is "don't worry and just enjoy", but having never had any other stock Ge FF whether what I am listening to at FF69 Fully CCW as per manual is like a stock Fuzz or not ?

[Plexi]

I can't understand what bothers you about this.. you want to reach the "stock" value?
As I can perceive, the 220R resistor is only for limiting the minimum value.
1k2 in total.
Like in the italian/'66 Tone Bender, using a 1K resistor there will give more output from the circuit.

[Mcentee2]

Wouldn't say I am "bothered" as that implies annoyance  -let's say intrigued and puzzled, but maybe  my question wasn't clear

The 1k Contour Pot and the 220r together give me a range of 220r-1.22kr - not a problem.

From this I can easily dial in 470r.

My question is relating this back to the manual where it says "Contour at full CCW gives you the stock FF" - which to me reads as 220r and not 470r.

Just wondering if this has been called out before and if any FT 69 users "ignore the manual" and set contour at about 11 o'clock (470r) or not to represent "stock".

And yes - I will set it where I like it, but I would also like to know if what I like is "stock FF" or not 

[Pedal love]

Off hand, I would say the bias resistor 220 changed because the (internal)10k pot changed the circuit. When this section changed, the bias above the output (contour) needed to change. Between(contour)and (internal) part of the q2 collector bias, there is a correlation between sections, ie. 470 and 8200 ohms. Because the (internal) is made of 1k and a 10k pot, the (contour) a 220 and 1k pot had to changed. The designers, probably had to make the tone the best they could, in any combination of the two (internal) and (contour) being tweeked.


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[kaycee]

I see what you are saying, but you could probably replace the 220 with a 470 and not hear any difference I suspect. I don't know why FT didn't us a 470 there, common to up the value there as it increases output volume.

I had a ge FF in for repair that someone had put a 10k in that spot, it was bloody loud and an absolute  stonker !