GFB 5701 Whistling Trumpet
The ability to change the sound of a blow-off valve is increasingly becoming an important issue with buyers, who want to sound different from everyone else.
The 5701 can be used in place of the standard trumpet on GFB valves (Part numbers T9003 & T9503), and will make a whistling sound. However, it is necessary to run the valve so that all (or most) of the air vents through the trumpet – Respons valves will typically not generate the velocity required to whistle when set to 50/50 venting.