java - addding some effect like echo to audio track using AudioTrack of android -

adding effect echo audio track using audiotrack of android, want add echo, robotic effect vice changer app.

if (selected_index > 6) {   audioeffect effect = new audioeffect(audioeffect.effect_auxiliary /*.effect_type_env_reverb*/ ,     audioeffect.effect_type_null 0,     0);   audioeffect    audiotrack.attachauxeffect(effect.getid());   audiotrack.setauxeffectsendlevel(1.0f);   //result =  true ;     effect.release();   audiotrack.release();