Measuring Backround Noise

Hi,
I have a problem. The noise that gets inside my apartment over night just went nuts in the past weeks. The landlord is behind me on that but needs hard data to do anything (and he’s not gonna get it..). So I got the idea to measure the soundlevels over night in my apartment myself and sleep somewhere else.
The scientific analysis of data is not going to be a problem. I did this before in college, only thing: they will not lend me the entire laboratory^^ But at least I have a friend, willing to lend me a descend microphone for studio-recording.
At the moment I see two basic ways to measure these noises:
1) A simple not time-dependent measurement of frequencies and amplitudes. Frequencies horizontal, amplitudes vertical while plotting the data. The analysis would lead to a two-dimensional graph (in German “Schmalbandspektrum”) with the biggest amplitudes for each frequency over the entire period of time. Pro: Easy to analyse, Contra: One noise on my part will ruin one night of recording.
2) The same thing, but dependent on time, so I basically get a three-dimensional image when done analysing with the time on the third axis. Pro: Very thorough analysis possible, even though the amount of data will be huge. But with Excel and Mathematica and a cluster at the university, this is not going to be an issue. Contra: Calculations will probably take some time, even on the cluster . But this is not going to be the reason for failure, it’s just numbers, no complicated functions or anything disgusting…
So the question for you guys is (hopefully there are some fellow-engineers around here or people with knowledge about recording): What besides a microphone do I need for such a measurement?. I read I’ll need an external sound-card with higher sensitivity than the one inside my computer, but what else do I need? Do you guys know any good software to measure anything like this? The best thing would be if I get a huge table with numbers at the end of the night…
Any kind of practical advice will be appreciated.
Thanks in advance
Answer #1
what you need is a PC capable decibel meter
http://www.amazon.com/40-130-Digital-Decibel-Pressure-Logger/dp/B004VUQU0E
google “usb decibel meter pc logging” for others
Answer #2
Thank you, I’ll check this out.
And as programm for basic visual analysis, I found that audacity has some basic features. But it’s not gonna be able to process such a big amount of data at once^^