It has been a long time since I wrote anything for this blog. I have gained some knowledge in one odd area or hobby that I would like to start sharing here in case this information is of use to others. The first topic I would like to share is regarding using Wireless transmission systems to synchronize music playback between Music Bikes.
First off, probably need to state what the heck a “music bike” is. These are bicycles modified in some way to carry sound equipment that provide for entertainment during social biking events typically called “Bike parties”. (See San Jose Bike Party for more info) These systems come in all shapes and sizes, with varying degrees of quality and volume. While they do provide for enjoyment, they can also be a nuisance at these bike events when they are playing different music too close together either during the ride portion, or during the rest stop or “party” portions of these events. This noise or train wrecking that happens has given rise to the need to synchronize the music across multiple music bikes. Wired methods are very good if you are stopped and can clump the bikes together, however wireless provides to the chance to synchronize these systems while moving, or to spread them out at the event to create mobile dance floors, or to also act as a connected PA system to disseminate important ride information to the participants.
What I have learned in this area has been by consulting experts who do these kind of things for a living, such as the “Rock The Bike” team who provide for pedal powered concerts and events, as well as by trial and error, and also by discussions within a group I administer on facebook called “Music Bikes“. I am not an engineer and have only my experience to share. I do not claim at all to know why some of these solutions work better than others, I just know what I have experienced.
I have also had a few “partners in crime” on these experiments, namely a few of the other organizers of one of these mobile parties that we founded last year called Guerillaz in Da Mixx. Joe & Jarek have helped quite a bit, and I have also received great advice from Jenny in LA with her wide amount of technical and practical knowledge as a ride leader in the Midnight Riddazz on her awesome music bike Mega Mundo.
The first system we explored was to use FM transmitters and FM receivers. FM receivers are easily accessible and cheap. FM transmitters (legal ones) can also be purchased at fairly low cost. The laws here require that they do not transmit past 200 feet. Legal ones seem to top out at .5W from what I found. Going beyond this is possible, but would get you in trouble with the FCC. We experimented a bit in this area but found that if the transmitter and receiver were both in motion, that the connection was not great and there was considerable static. We also found that even in a stationary setting, the addition of many persons (dancing) in between the transmitter and receiver caused interruptions in the signal, and in general just poor sound quality. This poor quality is not that noticeable at low volumes, but when broadcast through high volume music systems it was unbearable. None of the FM systems proved to be workable for our uses so we gave up on this.
The next system we tried was Channel Vision’s 2.4GHz home audio sharing solution. I tested this system with Music Bike member Ed from SF. We got this working OK during rides and at San Francisco Bike party. Sound quality again was just OK, and range not great. In the end we abandoned this approach as well.
At about this time, we were having lots of discussions on this topic in our Music Bikes group about other solutions. One suggestion from a member was to use a now discontinued logitech streaming server that could connect wirelessly over wifi or 3G and sync music playback. I did some testing of this with him around the streets of Mountain View. Based on using 3G, there is no limit to how far away this would work, however, when the 3G signal was interrupted during motion, the music would stop. The team from Boombotix who do the kool small portable speakers is developing something similar with their “mesh” technology. Concerns over the 3G connection made us abandon this path.
Next one that was tried was again a great group effort from the Music Bikes discussion group. So many inputs there, but I believe that Brian came up with the basic idea to use Apple Airplay with the Airfoil SW installed on a MAC used as a “server”. This was a kool concept where we could run Airfoil clients on smartphones (iOS or Android) that would connect over wifi through a router to the Macbook. Again, great in theory but not so great in practice. When we tested multiple systems out, they would lose sync often and have to log back in. Administering it was a difficult thing to do in the field. Range was OK at 100-150 feet, and we were able to extend it with some high end antennas. What killed the concept for us was a wake up call from our expert in LA Jenny, who reminded me that DJ’s need a live signal to work with and cannot mix against a delayed one. To facilitate the sync, the signal is delayed. Another attempted solution in the dust since a key usage for us for our Guerillaz in Da Mixx event was to have live DJ’s.
This now brings me to the system that we have settled on; the Shure PSM200. Credit for discovering this system and creating the usage model goes to the Rock The Bike team and once again Jenny from LA (MegaMundo) who shared more details with me. The Rock The Bike team uses this system for their “Live on Bike” performances at the Bicycle Music Festival. This is a system originally designed to allow for singers to get the full mixed sound sent to them wirelessly over a dual UHF signal that carries the full audio spectrum needed to reproduce music (vs others limited to just handle voice). It is much more expensive than the FM or other solutions, but they work great, all the time. We can get a solid 200 feet range with these, even when transmitter and receiver are in motion. We have connected up to 6 receivers to one transmitter and created an amazing experience with a mobile music bike posse that created an awesome experience for all the riders, and also a large and fully surround sound dance floor experience with live DJ’s. If the bikes get towards the end of the range during a ride, you can hear some slight delay happening, but for the most part it is a very solid experience.
There are other less expensive choices that again the Music Bike Members (SJRides) have found, but we have not tested these, such as the Galaxy AS-900 or the Koolertron New in ear system.
Thanks for reading. Checkout my Music Bike with a Shure system installed here: Orange Guerilla Bike + also checkout a few other interesting music bikes: