Nelson's "Citrus Graphic MKII" build report

[MartyMart]

This is probably the last of many "Jfet amp sims" that I'll build/create and it complete's
a superb set, including several ROG amp sims.
The ones that I've come up with are in the layouts gallery above ... so :
Nelson came up with this circuit a little while ago and I was very keen to make it, work
got in the way for several weeks, bit it was completed this morning.
I've never owned an "Orange" amp, so can't compare, but all I can say is ......

"Paul, this sounds superb" !

It's built as close as i could get to exact values, but I did a little "what I have" here and there,
These are:
Input resistor 47k not 68k
Treble cap 1000pf not 1500pf
Removed the multiple cap selection off Q2, as I have no 6 position pots, just used a straight 470n
cap from Q2 to the 100k.
Tried the boost as a pot/switch and decided just to leave it "boosted" permanently, if you like, with
1k and 0.47uf off Q3
Lastly, I just used one Roll off section of 15k/2n2 at the end rather than two.

The only mistake was that my Bass pot works backwards, perhaps the schem could say "lug 1" at the
top for that one, treble was wired the same and works correctly, the circuit was biased to around 4.5v
on all four J201's and fired up first go
Lots of sounds available from this one, from clean / bright and spanky, through to Fat/ whooly Fuzz Face
type tones and there's a decent anount of drive at the top end.

FABULOUS   

MM.

[nelson]

I have STILL to build this one 


Thanks for the build report.



This one should lend itself well to "stoner" tones.



What do you think Marty?

[MartyMart]

Yup !
Very flexible, one of the most flexible Jfet sim's IMO !
Good "stoner" tones, it gets very "Big Muff" with the bass up and gain cranked

MM.