Javaman

Yep. None of the upgrades mentioned will help reduce the sound or do anything useful for that matter, except for anti-syphon unless your tank in at a down angle, until you can regulate the pressure down. Some of the fancier valves/pins might even be damaged if run at full CO2 pressures of 850psi. The Palmer Stabilizer is an excellent one for both CO2 and HPA but it's a bit on the pricey side at $85.

(ever notice that low pressure valves are like women's clothes? The less material, the more expensive?)

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