Bemix is a music system which plays user selected music in the Bemis bathroom. Residents can select music over a web interface and can turn the music on and off directly from the bathroom or remotely over the web.
There are three versions of Bemix:
- Bemix v1.0 - the original version, it has since been uninstalled to be upgraded.
- Bemix v2.0 - the current version and will be installed shortly.
- Bemix v3.0 - this version is under development.
Bemix v1.0 was designed to play music in the Bemis showers through speakers located in the Bemis bathroom. It plays music selected through Glirnath, a web interface. You can control it via Glirnath or a touch-switch located in the bathroom.
The touch-switch was hidden in a towel rack in the Bemis bathroom. When someone touched the towel rack and the faucet at the same time, the op-amp senses the change in voltage, compares it to an internal reference voltage, and amplifies it. This signal is sent to a flip flop which toggles power to the speakers.
Bemix v2.0 is the current version of the Bemis bathroom music system. It will span the three central bathrooms: Bemis, shallow Goodale, and shallow Walcott. At present, we have all necessary hardware and software. It will be fully operational following the installation of cable trays on 4E.
The hardware consists of a touch switch in each bathroom and a central logic circuit. The touch switch uses a commercial IC (QT1013?) made for this purpose for improved reliablilty. The logic circuitry is built around flip flops, one for each bathroom. Each flip flop is toggled by the remote touch switch, the computer, and a control panel which has not yet been implemented. The output is sent to the computer so that it can play or stop the music in the appropriate bathroom.
On the computer side, we are using a 700MHz PIII with three sound cards to. It will be running custom software written in python.
Bemix v3.0 will be a complete redesign of v2.0. It will be [PIC] based and will communicate with the computer over the 4E network. This will allow a virtually unlimited number of commands to be exchanged between the bathrooms and server. In order to keep the hardware simple, we will continue to transmit analog audio from the computer to speakers in each bathroom.
We plan to install a small unit in each bathroom with an LCD display and several buttons. The LCD will provide a readout of the current playlist and the buttons will let you start and stop the music, move forward and back in the playlist, and switch between playlists.