ESP32 max. sampling rate

    
     #include 
        #include 
        #define AUDIO_IN_PIN 35
        
        int analogValue; 
        float newTime; 
        
        void setup() {
          Serial.begin(115200);
        
        }
        
        void loop() {
        
        newTime = micros();
        Serial.print("\n... | Measurement runs: ||||||||||||||||| \n");
        Serial.print(newTime);
        Serial.print("\n");
        
        // 1 Mio reads and record time take for this 
        for (int i = 0; i < 100000; i++)
        {
          analogValue = analogRead(AUDIO_IN_PIN);
        }
        // calculate 
          float conversionTime = (micros() - newTime)/100000.0;
        
        // report 
          Serial.print("Conversion time: ");
          Serial.print(conversionTime);
          Serial.print(" uS");
        
          Serial.print("\n Max. sampling frequency: ");
          Serial.print( (1.0/conversionTime)*1e6);
          Serial.print(" Hz");
        
          Serial.printf("\n Fs: %.5f", (1.0/conversionTime)*1e6);          
        
        }