Adding weight is always the fastest way to decrease bow noise. If low noise is really important to you, there is no reason to limit yourself to traditional methods.

Some don't like the STS type devices. They stop vibration, but add a slight "tunk" on the shot. You can put multiple silencers on the string and cables. I've had some super quiet setups that had anywhere from 6-8 string silencers on it. If you shoot with a string loop, change it to a Catfish Loop. It acts as a silencer as well as the best loop you can have on your bow. You can also shoot a higher strand-count string. It will weigh more, make less noise, and adds strength to your string.

Do all this and then pop a 600 grain arrow onto the string and you'll be lucky to hear anything on the shot.