how do you test it m8, thinking as its something ive never done to mine?
what you may be able to do is electrically "piggyback" another siren into the existing circuit that powers then siren when triggered, this then could be mounted anywhere, im sure maplins do a tiny siren thats 122db thats easilly connected.
tried to connect another siren to it but the original one has three wires.tried to connect using different combinations but one just sets the siren off all the time and the other nothing happened.just wondered if another audi one was louder.i just opened the door with the key and waited for the alarm to go off.
i cut the siren box open and connected my new siren direct to the output wires and it was still very low,but if i put 12v to the new siren its very loud.going to try and find a louder one from a vag breaker.
could you not fit the siren into the existing system via a relaly?
then what ever the voltage triggering the oe siren, this would trigger the new siren to be powered via 12 volts direct from the battery, result one mo fo loud siren.