I’m building an isolation booth for drums in my garage.
Drums are loud. In terms of decibels, John could probably play at 120dB easily. Comfortable speech levels outside are at about 70dB, so we need about 50dB of attenuation between the drums and the outside.
Here’s a plot of the attenuation we have, with no box, with the box itself, and with the box and the enclosing garage.
The box provides about 15dB of attenuation right now, though it is essentially transparent at 160Hz, 250Hz, and 500Hz. It’s 8 feet long, so that’s a round trip time of 16msec or so. We’d expect a resonance around 60Hz. Or this could be the self-resonance of the walls or window. Clearly we need some damping to improve this.
The garage doesn’t block anything below 100Hz, but it’s good for 10-15dB above that.
Need another 15 db overall to get to our target of 50dB of attenuation. I’m thinking a second layer of ply with some kind of damping or absorbtion will be necessary. Might be best to experiment with curtains or light duty acoustic tiles and then decide if we need the extra plywood.
I’ve been away from the blog for the last couple of weeks because I’ve been trying to keep up with a new job and meeting a ton of people. The company I’m at has hired literaly hundreds of interns this summer and it’s really interesting to see how relationships have formed and evolved over time and parallels between relationships and the formation of a crystal.
In the initial stages we interns were flown in from across the country and put through orientation, group lunches and training. Most people knew maybe one or two other people and we were all excited to meet each other because most people were from out of town and didn’t have much to do. The state of things was kind of like a gas with a lot of random interactions between energetic particles.
Very quickly, within a matter of hours, numbers and email addresses were exchanged, people looked each other up on facebook, and events started to be planned. People initially went out on large group outings where the attraction was as much meeting new people as going and doing something. At that point people might have had a few friends, but nothing really that serious. As people are able to meet their social needs, their incentive to meet new people diminishes and less effort is spent on risk taking and initiating social contact.
Now three weeks into the process, arcs of communication have solidified. Some links are strengthened by repeated positive feedback and some links have atrophied and been eliminated. Even a few repulsive links have formed.
Some interesting observations:
- People have a finite amount of linkage to allocate to their friends and a desire to socialize that causes them to reach out to random people. Increasing this capacity to reach out seems to be the key to having a good network.
- Early on people seem to affiliate based on school, proximity of housing. The “cool” people in the group seem to seek each other out, and coolness is best communicated through physical attractiveness and dress. This might mean living on campus next Fall is the right thing to do.
- Repulsive links tend to have a stronger impact on event planning that attractive links. People will give up a lot to avoid unpleasant experiences and people.
- A lot of what drives grouping behavior is transportation. I’m so much more popular now that I have a car and a lot of the interns dont. Other shareable resources that form a point of community might be TV, a hot tub, or a BBQ.
It will be pretty cool to see how this evolves. It’s always exciting to be thrown into a new group of people. I should try to make sure this happens often.
