KUJOBUY Wireless USB Gaming Receiver Adapter Compatible with Microsoft Xbox 360 Controllers, Desktop PC Laptop Gaming Adapter for Windows PC

Q: Will just one of these adapters work with 4 controls?

I've successfully connected 2 controllers simultaneously. I have not tried more than 2, although I bet it would.

Q: can you connect two controllers at once?

No, the usb controller pod will only pair with one controller at a time. You will need another one to connect another controller that one.

Q: Can this connect edrums for rock band ?

I use this for my wireless xb360 guitar hero guitars. Be sure to go through device manager and update the drivers to "Xbox 360 peripherals." There's plenty of YouTube videos. You can also connect more than one device simultaneously. I've used 2 guitars on the same reciever. Cannot speak on 3+ devices though.