rdn参数用于设置数字的读法,设置rdn=1,“66000”会读成六万六千;设置rdn=2,会读成六六零零零零;
设置:

SpeechSynthesizer mTts= SpeechSynthesizer.createSynthesizer(context, null); 
mTts.setParameter(SpeechConstant.VOICE_NAME, "xiaoyan"); 
mTts.setParameter(SpeechConstant.SPEED, "50");
mTts.setParameter("rdn", "2");