|
|
|
@@ -1,115 +1,7 @@ |
|
|
|
/* |
|
|
|
Change the chorus code to produce a flange effect |
|
|
|
|
|
|
|
PROC/MEM 25/4 |
|
|
|
140204 |
|
|
|
d |
|
|
|
- fixed the problem with user-supplied delay line |
|
|
|
|
|
|
|
140203 |
|
|
|
c |
|
|
|
|
|
|
|
140203 |
|
|
|
b |
|
|
|
- when switching to/from passthru, keep the delay line filled |
|
|
|
BUT to be effective must also fix up begin and add another |
|
|
|
function to allow changing to/from passthru without |
|
|
|
reinitialing everything. |
|
|
|
|
|
|
|
I have mixed up the names "chorus" and flange". The sketches named |
|
|
|
chorus have, up to version 'm', actually implemented a flanger. |
|
|
|
From version 'o' onwards the sketches named chorus will implement |
|
|
|
a real chorus effect and flange will do a flanging effect. |
|
|
|
|
|
|
|
140202 |
|
|
|
a |
|
|
|
Modify filter_test_f to try out a chorus effect |
|
|
|
|
|
|
|
m + n only changed the effect parameters |
|
|
|
- |
|
|
|
140201 |
|
|
|
l - found the problem at last using my_flange_cd_usd_c |
|
|
|
YES! Way back when I found I hadn't been using d_depth. Now I |
|
|
|
have just discovered that I haven't been using delay_offset!!!!! |
|
|
|
|
|
|
|
140201 |
|
|
|
k |
|
|
|
interpolation doesn't remove the ticking |
|
|
|
|
|
|
|
140131 |
|
|
|
j |
|
|
|
>>> The lower the frequency, the less ticking. |
|
|
|
- try interpolation |
|
|
|
140201 |
|
|
|
- got this restored to the way it was last night |
|
|
|
and then reinstated the changes. I had a couple of |
|
|
|
changes to the right channel that were incorrect or |
|
|
|
weren't carried over from the left channel changes |
|
|
|
|
|
|
|
i |
|
|
|
- don't know why but this version seems to have more "presence" |
|
|
|
than previous versions. |
|
|
|
The presence occurred when "sign = 1" was put in front of the left. |
|
|
|
It essentially makes it a passthrough. |
|
|
|
If both have "sign=1" then it is identical to passthrough |
|
|
|
|
|
|
|
Ticking is still not fixed |
|
|
|
|
|
|
|
h |
|
|
|
- add sign reversal. It seems to make audio much clearer |
|
|
|
BUT it hasn't got rid of the ticking noise |
|
|
|
|
|
|
|
g |
|
|
|
- I wasn't even using delay_depth!!!! |
|
|
|
|
|
|
|
140131 |
|
|
|
f |
|
|
|
- added code to print the processor and memory usage every 5 seconds |
|
|
|
NOW the problem is to try to remove the ticking |
|
|
|
|
|
|
|
140219 |
|
|
|
e |
|
|
|
FOUND the problem with the right channel. It was also in the left channel |
|
|
|
but the placement of the delay line arrays made it more noticeable in the |
|
|
|
right channel. I was not calculating idx properly. In particular, the |
|
|
|
resuling index could be negative. |
|
|
|
|
|
|
|
I have shortened the delay line to only 2*AUDIO_BLOCK_SAMPLES |
|
|
|
|
|
|
|
- removed redundancies in the update code. rewrite the block |
|
|
|
instead of getting a new one |
|
|
|
Haven't solved the noise in the right channel yet. |
|
|
|
Tried duplicating right channel code to left but noise stays on the right |
|
|
|
|
|
|
|
140130 |
|
|
|
d |
|
|
|
The noise stays in the right channel even if it is calculated first |
|
|
|
Switching the L/R inputs doesn't switch the noise to the left channel |
|
|
|
|
|
|
|
c |
|
|
|
>> Now add a sinusoidal modulation to the offset |
|
|
|
There's an awful noise in both channels but it is much louder in |
|
|
|
the right channel. NOPE - it is ONLY in the right channel |
|
|
|
but the audio does sound like it is working (sort of) except that it |
|
|
|
is rather tinny. Maybe it needs to have the interpolation added. |
|
|
|
|
|
|
|
b |
|
|
|
- this works with clip16_6s.wav. |
|
|
|
The original of this audio file was from http://www.donreiman.com/Chorus/Chorus.htm |
|
|
|
I reworked it with Goldwave to make it a stereo WAV file |
|
|
|
But with Rick Wakewan's Jane Seymour it seems to act more like |
|
|
|
a high-pass filter. |
|
|
|
|
|
|
|
a |
|
|
|
- removed FIR stuff and changed the name to AudioEffectChorus |
|
|
|
it's basically a blank template and compiles. |
|
|
|
|
|
|
|
From: http://www.cs.cf.ac.uk/Dave/CM0268/PDF/10_CM0268_Audio_FX.pdf |
|
|
|
about Comb filter effects |
|
|
|
Effect Delay range (ms) Modulation |
|
|
|
Resonator 0 - 20 None |
|
|
|
Flanger 0 - 15 Sinusoidal (approx 1Hz) |
|
|
|
Chorus 25 - 50 None |
|
|
|
Echo >50 None |
|
|
|
|
|
|
|
FMI: |
|
|
|
The audio board uses the following pins. |
|
|
|
@@ -159,8 +51,8 @@ many blocks you provided with AudioMemory(). |
|
|
|
// The delay line for left and right channels |
|
|
|
short delayline[FLANGE_DELAYLINE]; |
|
|
|
|
|
|
|
// If this pin is grounded the FIR filter is turned which |
|
|
|
// makes just pass through the audio |
|
|
|
// If this pin is grounded the effect is turned off, |
|
|
|
// which makes it just pass through the audio |
|
|
|
// Don't use any of the pins listed above |
|
|
|
#define PASSTHRU_PIN 1 |
|
|
|
|
|
|
|
@@ -174,10 +66,10 @@ AudioEffectFlange myEffect; |
|
|
|
AudioOutputI2S audioOutput; // audio shield: headphones & line-out |
|
|
|
|
|
|
|
// Create Audio connections between the components |
|
|
|
// Both channels of the audio input go to the FIR filter |
|
|
|
// Both channels of the audio input go to the flange effect |
|
|
|
AudioConnection c1(audioInput, 0, myEffect, 0); |
|
|
|
AudioConnection c2(audioInput, 1, myEffect, 1); |
|
|
|
// both channels from the FIR filter go to the audio output |
|
|
|
// both channels from the flange effect go to the audio output |
|
|
|
AudioConnection c3(myEffect, 0, audioOutput, 0); |
|
|
|
AudioConnection c4(myEffect, 1, audioOutput, 1); |
|
|
|
|
|
|
|
@@ -220,16 +112,35 @@ int s_depth = FLANGE_DELAY_LENGTH/8; |
|
|
|
double s_freq = .0625; |
|
|
|
*/ |
|
|
|
|
|
|
|
//12 - good with Eric Clapton Unplugged |
|
|
|
/* |
|
|
|
//12 - good with Eric Clapton Unplugged |
|
|
|
int s_idx = 3*FLANGE_DELAY_LENGTH/4; |
|
|
|
int s_depth = FLANGE_DELAY_LENGTH/8; |
|
|
|
double s_freq = .0625; |
|
|
|
*/ |
|
|
|
|
|
|
|
/* |
|
|
|
// Real flange effect! delay line is 2* |
|
|
|
int s_idx = 2*FLANGE_DELAY_LENGTH/4; |
|
|
|
int s_depth = FLANGE_DELAY_LENGTH/4; |
|
|
|
double s_freq = 2; |
|
|
|
*/ |
|
|
|
|
|
|
|
/* 2 - |
|
|
|
int s_idx = 2*FLANGE_DELAY_LENGTH/4; |
|
|
|
int s_depth = FLANGE_DELAY_LENGTH/8; |
|
|
|
double s_freq = 4; |
|
|
|
*/ |
|
|
|
/* |
|
|
|
// 4 |
|
|
|
int s_idx = FLANGE_DELAY_LENGTH/4; |
|
|
|
int s_depth = FLANGE_DELAY_LENGTH/4; |
|
|
|
double s_freq = .25; |
|
|
|
*/ |
|
|
|
// 4 |
|
|
|
int s_idx = FLANGE_DELAY_LENGTH/4; |
|
|
|
int s_depth = FLANGE_DELAY_LENGTH/4; |
|
|
|
double s_freq = .5; |
|
|
|
|
|
|
|
void setup() { |
|
|
|
|
|
|
|
Serial.begin(9600); |
|
|
|
@@ -256,11 +167,11 @@ void setup() { |
|
|
|
} |
|
|
|
|
|
|
|
// Set up the flange effect |
|
|
|
// address of delayline |
|
|
|
// total number of samples (left AND right) in the delay line |
|
|
|
// Index (in samples) into the delay line for the added voice |
|
|
|
// Depth of the flange effect |
|
|
|
// frequency of the flange effect |
|
|
|
// - address of delayline |
|
|
|
// - total number of samples (left AND right) in the delay line |
|
|
|
// - Index (in samples) into the delay line for the added voice |
|
|
|
// - Depth of the flange effect |
|
|
|
// - frequency of the flange effect |
|
|
|
myEffect.begin(delayline,FLANGE_DELAYLINE,s_idx,s_depth,s_freq); |
|
|
|
|
|
|
|
// I want output on the line out too |
|
|
|
@@ -284,7 +195,7 @@ void loop() |
|
|
|
volume = n; |
|
|
|
audioShield.volume((float)n / 10.23); |
|
|
|
} |
|
|
|
if(1) { |
|
|
|
if(0) { |
|
|
|
if(millis() - last_time >= 5000) { |
|
|
|
Serial.print("Proc = "); |
|
|
|
Serial.print(AudioProcessorUsage()); |
|
|
|
@@ -302,7 +213,7 @@ if(1) { |
|
|
|
b_passthru.update(); |
|
|
|
|
|
|
|
// If the passthru button is pushed, save the current |
|
|
|
// filter index and then switch the filter to passthru |
|
|
|
// filter index and then switch the effect to passthru |
|
|
|
if(b_passthru.fallingEdge()) { |
|
|
|
myEffect.modify(DELAY_PASSTHRU,0,0); |
|
|
|
} |
|
|
|
@@ -313,7 +224,3 @@ if(1) { |
|
|
|
} |
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Pete (El Supremo)
10 년 전