There are different ways to project sound to a large number of people. Two things to consider
1. The quality of the sound out to the individual
2. The cross talk among the wireless devices
If you are looking for quality of the sound, the wireless opting might limit some of the frequencies to the individual device. If sound quality is not a problem then wireless might work
The major problem of wireless devices is the high frequency cross talk and noise reduction. I am not sure how good can blue tooth technology can be here as the is a limitation to how many devices can be used per hub. That being said, you can ignore other forms of technologies out there like a small power short length FM transmitter, each device will receive the sound from the transmitter and amplify for each user. This technology can be similar to a wireless microphone.
Hi. Please clarify: you said to ignore other forms of tech because each device will recieve the sound and amplify for each user? That is exactly what i want, no? I want each device receive sound from the transmitter and amplify for each user. So are you saying a small power short length FM transmitter is the way to do what im trying to do?
I meant that you cannot ignore the other types for transmitting devices. Most likely a small RF transmitter would be the best here. All the receiving devices will be getting signal similar to a FM radio or a wireless microphone and process it. Yes, a small low power FM transmitter would be a better choice here.
See below the link for a small FM transmitter