GC_ET_AFX_CW_RIT.html

*** Hedge f() by shifting the Stage #4 f() within the source pasband, to better capture a slightly QSY signal.

Hedging R.I.T. control:
:::: Here, R11 is R(freq) and is adjusted aprox. +/- 2KOhm to vary f() aprox. +/- 100Hz within the source passband.

( author uses a Panel Pot for hand control.)
( Is used as a Hedging control to push BandPass Peak Freq against a BandPass Skirt wall. )

* Used to "tune" the bandpass to suit the ear,
* for example, setting the f(center) from 650 Hz to 700 Hz to 750 Hz , in real-time.

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Here, the RIT method is tested in an isolated stage.
___ f()=700_"Q"=7.0_BW=100_ presented in s Single Stage MFB circuit.

Varying R(freq) alters f(center) bounded only by the BandPass of the Source Signal.

Notice how FAR the f() varies as R(freq) is adjusted.
Shows the amount of practical variance ( 350Hz to 1400Hz) on a single stage MFB filter circuit.

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Below is the simple basic circuit used in Spice to test this function and produce the RIT Bode.
Each Stage Is The SAME, R.I.T. Variations are done by adjusting R(freq) .

These Bodes are the further results in a full AFX circuit of Four Stages.

These Bode plots are what the AFX (full circuit) has during normal operation.
The shape of the curve is bounded by the source signal.
If the Prior stage passband is 200 Hz, then the variance will follow that limit.
If the Prior stage passband is 2K Hz, then the variance will follow that limit.

The very last Bode is the result of increasing Stage 4 gain by 3X
( Has Same Shape just amplified in comparison to Stages 1,2,3. ).

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*** Experiments with R.I.T. of Fx04
in the AFX Quad Filter set.

*** R.I.T. is Useful in tuning the Fx04 pitch to suit the user's ear.
*** and forcing ( Hedging ) an unwanted signal off the opposite sideband.

*** Bodes for R.I.T. : Hedging the Fx04 stage, within the Fx03 stage.
*** Hedging on Fx04, within Fx03, will follow the band-pass of Fx03.
*** DIF bode is dropping -0.3dB ( not audible ).
*** INT bode is varying +1.0dB ( just audible ).
***
*** Howwever, these bodes show some limits of Hedging
*** and interaction within "W" INTgrating stage band-pass.
*** If Fx04 is Hedged, then INT bandpass is offset and peaked by about 1.5 dB.
*** Should be noted that the net effect to the ear is barely detectable.

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