I’m working on a project where I need lots of bicycle sounds. Being an enthusiastic cyclist myself I decided to start creating my own bicycle sound library for this and future projects.
First on my shopping list are good and isolated tire sounds on different surfaces. To get a microphone close enough to the point where tire meets ground I first decided to use something like Super Clamp inspired by this Nathan Moody’s article. However, I couldn’t attach a Super Clamp onto the front fork without the clamp touching the spokes, so I used my old K&M mic holder instead. It has a long arm that made it possible to mount the holder up where there’s more space between the fork and the spokes and still get the mic close enough to the ground.
The microphone is Line Audio CM3, a super small and well-priced condenser with surprisingly good quality made in Rinkaby, Sweden. The mic is attached with a rubberband suspended holder. As I don’t own a Rycote Baby Ball Gag or a similar small windshield, I used a dead kitten from my pocket recorder and attached it with two safety pins.
As a bonus I decided to simultaneously record the rear hub, gear shiftings, etc as well, even though that wasn’t my priority. For that I used a another CM3 and a Super Clamp. However during the first test my shoe ankle hit the clamp, and next thing I noticed was that the microphone holder had broken and the mic had dropped somewhere between the spokes and the cassette. I don’t know what happened, but luckily the microphone didn’t break. For the actual test ride I attached the mic on the other side, but couldn’t find a place where it would have been out of the way of my shoe. So I had to keep my feet in an awkward position to avoid hitting the clamp.
It’s now winter in Finland where I live and even the capital Helsinki on the southern coast is covered with snow. So let’s start with snow sounds! I connected the mics into my SD702 and went out. Minus 20 Celsius made sure my first test ride was very compact in length! I rode on as many different surfaces as I could quickly find in my urban neighbourhood, but I think the most interesting was lawn covered with a few centimeters of snow.
And here’s an example of what I got:
I really like the rich snow sound. The close miking also works nicely and isolates the city ambience and traffic around. There was, however, a heavy resonance from the bicycle frame around 30 Hz, which caused strong rumbling sound all the way up to around 180 Hz. With a simple HPF I managed to clean that quite nicely, but that’s something I must take a look at for the next rides. Maybe get a better or an extra suspension system. Also the rim has its own ringing sound, so I might need to try mounting the tire on another kind of wheel.
Here’s an example from the rear mic:
This is a different part of the ride. First there’s some asphalt with sand on it, then gravel and finally I climb stairs on foot carrying the bike. I think the rear mic is not too useful for my use, as the hub and gears make quite soft sounds and the mic captures a lot of ambience instead. I believe with these details I’ll get better results in a studio environment.
To sum up, I think with slight improvements with the mic suspension the front rig works nicely. For my sound collecting purposes mono recordings are fine, but I might experiment with an MS rig using a CM3 and an ATE208 which I use with my shotgun mic. Not being a perfect combination that would however be easier to set up than an XY with two CM3’s. I’ll keep posting my results.