Hard to Hear Shot Timer at Indoor Range

[BCGlocker]

I use two different shot timers for my own practice as well as for the LTC Proficiency Test. However, at my local indoor range, the ventilation system is so noisy, that the student’s two lanes from me cannot hear the timer. Does anyone know a way to add speakers to CED 7000 or Pocket Pro shot timer? BTW, I downloaded “Make Ready” iPhone shot timer, but for unknown reason, it will not broadcast the buzzer sound over Bluetooth speakers.

Is there a better way to do this?

[joe817]

I'm an outsider looking in, but I'd think doing it manually using a bullhorn megaphone, or a marine airhorn would suffice and insure all the people could hear it.