I'm using the cats with a 1,2 metre hotdog. It doesn't sound to loud. Maybe shove some wire down the pipes?
Speaking of cats. A few years back I whent to a break down, and the member said that he would try to start the car, then when he let go of the key, it would make a sound like a sick starter. It did this several times. So I opened the bonnet and there was a cat all tangled up in the fan belt. It was face down hanging under the car, not looking healthy. So I rang the superviser trying to work out what to do. One suggestion was to ring the police, and come and shoot it, and put it out of misery. I thought I'll try and untangle it. So I loosened the alternator and removed the fan belt, and it looked like it never broke it's skin because it wasn't bleeding, but it dropped out onto the road and lay there for a while. Then it cashed in a few of it's lives and ran of.
JD