[Asterisk-Users] Slightly OT - Anyone know of an external ringer compatible with Cisco phones

[izo]

On 11/22/05, Cory Andrews <Cory at voipsupply.com> wrote:
> Have an application where Cisco phones are being used in a noisy
> environment....looking for some type of external ringer or amplifier so
> users can hear the phones ringing over the background noise.  Anyone
> familiar with such a device?

What about customized ringtone alarm like ?

The other idea is to plug something in between
handset cable so you can detect voltage that i belive is sent over the cable to
the nice red light on the handset itself.
How many devices like that would u need ?