Vocoder effect doesn't work.

I’m trying to use the vocoder effect but it doesn’t work.

I’m on Windows 10, using Audacity v. 2.2.2

I tried following a tutorial: I imported a voice file and made it the left channel, and put a sawtooth tone in the right channel. Then I combined them into a stereo track, then I higlighted it and tried running the Vocoder effect with various parameters.

When I run it the tracks are unchanged. When I check the debug window it says:

error: (a2 <= -1) or (1 - a2 <= |a1|) (unstable parameters a1 = -1.99997, a2 = -1.00089) in biquad

Function: #<Subr-ERROR: #edd88f0>
Arguments:
  "(a2 <= -1) or (1 - a2 <= |a1|) (unstable parameters a1 = -1.99997, a2 = -1.00089) in biquad\n"
Function: #<FSubr-IF: #edda320>
Arguments:
  (OR (<= A2 -1) (<= (- 1 A2) (ABS A1)))
  (ERROR (FORMAT NIL "(a2 <= -1) or (1 - a2 <= |a1|) (~A a1 = ~A, a2 = ~A) in biquad~%" "unstable parameters" A1 A2))
Function: #<FSubr-LET: #edd5a40>
Arguments:
  ((A0R (/ 1 A0)))
  (SETF A1 (* A0R A1) A2 (* A0R A2))
  (IF (OR (<= A2 -1) (<= (- 1 A2) (ABS A1))) (ERROR (FORMAT NIL "(a2 <= -1) or (1 - a2 <= |a1|) (~A a1 = ~A, a2 = ~A) in biquad~%" "unstable parameters" A1 A2)))
  (SND-BIQUAD X (* A0R B0) (* A0R B1) (* A0R B2) A1 A2 0 0)
Function: #<Closure-NYQ:BIQUAD: #ec34fd0>
Arguments:
  #<Sound: #9c1f4b8>
  -0.000447076
  0
  0.000447076
  0.999553
  -1.99907
  -1.00045
Function: #<Closure-NYQ:BIQUAD-M: #ec34890>
Arguments:
  #<Sound: #9c1f4b8>
  -0.000447076
  0
  0.000447076
  0.999553
  1.99907
  1.00045
Function: #<FSubr-LET*: #edd8330>
Arguments:
  ((W (* 2 PI (/ HZ (SND-SRATE X)))) (CW (COS W)) (SW (SIN W)) (ALPHA (* SW (SINH (/ 0.5 Q)))) (A0 (+ 1 ALPHA)) (A1 (* -2 CW)) (A2 (- 1 ALPHA)) (B0 ALPHA) (B1 0) (B2 (- ALPHA)))
  (NYQ:BIQUAD-M X B0 B1 B2 A0 A1 A2)
Function: #<Closure-NYQ:BANDPASS2: #ec32610>
Arguments:
  #<Sound: #9c1f4b8>
  8077.56
  34.0577
Function: #<Subr-APPLY: #edd7040>
Arguments:
  #<Closure-NYQ:BANDPASS2: #ec32610>
  (#<Sound: #9c1f4b8> 8077.56 34.0577)
Function: #<FSubr-SETF: #edd5860>
Arguments:
  (AREF RESULT I)
  (APPLY FN (MAPCAR (FUNCTION (LAMBDA (A) (COND ((ARRAYP A) (AREF A I)) (T A)))) ARGS))
Function: #<FSubr-DOTIMES: #edd9280>
Arguments:
  (I LEN)
  (SETF (AREF RESULT I) (APPLY FN (MAPCAR (FUNCTION (LAMBDA (A) (COND ((ARRAYP A) (AREF A I)) (T A)))) ARGS)))
Function: #<FSubr-COND: #edd8990>
Arguments:
  (LEN (SETF RESULT (MAKE-ARRAY LEN)) (DOTIMES (I LEN) (SETF (AREF RESULT I) (APPLY FN (MAPCAR (FUNCTION (LAMBDA (A) (COND ((ARRAYP A) (AREF A I)) (T A)))) ARGS)))) RESULT)
  (T (APPLY FN ARGS))
Function: #<FSubr-LET: #edd5a40>
Arguments:
  (LEN NEWLEN RESULT)
  (DOLIST (A ARGS) (COND ((ARRAYP A) (SETF NEWLEN (LENGTH A)) (COND ((AND LEN (/= LEN NEWLEN)) (ERROR (FORMAT NIL "In ~A, two arguments are vectors of differing length." FN)))) (SETF LEN NEWLEN))))
  (COND (LEN (SETF RESULT (MAKE-ARRAY LEN)) (DOTIMES (I LEN) (SETF (AREF RESULT I) (APPLY FN (MAPCAR (FUNCTION (LAMBDA (A) (COND ((ARRAYP A) (AREF A I)) (T A)))) ARGS)))) RESULT) (T (APPLY FN ARGS)))
Function: #<Closure-MULTICHAN-EXPAND: #ebc3d00>
Arguments:
  #<Closure-NYQ:BANDPASS2: #ec32610>
  #(#<Sound: #9c1f4b8> #<Sound: #9c197c0>)
  8077.56
  34.0577
Function: #<Closure-BANDPASS2: #ec32d70>
Arguments:
  #(#<Sound: #9c1f4b8> #<Sound: #9c197c0>)
  8077.56
  34.0577
Function: #<FSubr-SETF: #edd5860>
Arguments:
  BAND
  (BANDPASS2 S F Q)
Function: #<FSubr-DO*: #edd6f90>
Arguments:
  ((I 0 (1+ I)) MOD-ENVELOPE BAND (RESULT 0) (Q (/ (SQRT 2) (/ OCTAVES BANDS))) (P (+ (HZ-TO-STEP 20) (/ INTERVAL 2)) (+ P INTERVAL)) (F (STEP-TO-HZ P) (STEP-TO-HZ P)))
  ((= I BANDS) RESULT)
  (SETF BAND (BANDPASS2 S F Q))
  (SETF MOD-ENVELOPE (LOWPASS8 (S-ABS (AREF BAND 0)) (/ F DST)))
  (SETF RESULT (SUM RESULT (BANDPASS2 (MULT MOD-ENVELOPE (AREF BAND 1)) F Q)))
Function: #<Closure-VOCODER: #ed69c68>
Function: #<FSubr-SETF: #edd5860>
Arguments:
  S
  (VOCODER)
Function: #<FSubr-LET: #edd5a40>
Arguments:
  ((ORIGINAL (OR (= MST 0) (AREF S 0))))
  (SETF S (VOCODER))
  (SETF S (SCALE (/ (PEAK S NY:ALL)) S))
  (CASE MST (0 S) (1 (VECTOR ORIGINAL S)))
Function: #<FSubr-COND: #edd8990>
Arguments:
  ((ARRAYP S) (MIX) (LET ((ORIGINAL (OR (= MST 0) (AREF S 0)))) (SETF S (VOCODER)) (SETF S (SCALE (/ (PEAK S NY:ALL)) S)) (CASE MST (0 S) (1 (VECTOR ORIGINAL S)))))
  (T "Error.\nStereo track required.")
1>

Thanks.

I need to know what settings you are using.

The default settings as shown here, work fine for me:

Are you applying the effect to a low sample-rate track?
The track sample rate is shown in the panel on the left end of the track.

If the sample rate is less than 44100, use the “Tracks menu > Resample” command to resample the track to 44100 before you apply the vocoder effect.

I tried resampling to 44100Hz and now it works fine. Thank you. :smiley:

I’ve recieved the same error code, I’ve changed everything that needs to be changed, these are my settings for the vocoder.
Capture.PNGaaa.PNG
The rate is 44100 hz and its a stereo track with the voice on the left and a square-ish tone on the right channel. I’ve been messing with the settings for a while and its still not working. I’m using Windows 10 and Audacity 2.3.3

Run the effect with the Debug button, then copy the contents of the Debug window and paste it into your reply.