EMA Cross with adjustable Audio Alert

Hello. I was hoping someone knows where I can find or help. I have looked all over the place for EMA Crossover with an alert I can choose. This is because I need to have a loud noise when they Cross. The alert Wav is not loud enough. I prefer it to just keep going until I turn it off.

As long as it works on the 15 minute timeframe it would be great.

Thanks in advance.