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Everything you wanted to know about classic recording microphones, but were afraid to ask: This site goes into excruciating detail about classic ribbon, dynamic, and condenser microphones used for voice recordings in years past. The site even provides voice recordings made with some of the mics listed on the site (MP3 format, which I imagine has altered the sound somewhat).
The Hartford Courant notes that some restaurants are just too darn loud. The article blames increased noise levels in part on the trend of modern restaurants to replace sound-absorbing curtains, carpets and other treatments with hard surfaces like plaster, stone and glass. Essentially these hard surfaces make the restaurant space more reverberant (“live”), which allows noise to “build up.” The article also offers some quick and dirty recommendations for applying absorption.
You have to be careful about the recommendations given in the article. An architect suggests adding materials like vinyl and egg-crate foam, but you need to make sure that the vinyl or foam you select is actually sound absorbent. In particular there are several types of egg-crate foam that are not sound absorbing.
The Boston Globe tells us that research designed to help predict tsunamis may be harming marine life. The acoustics techniques being used (apparently some sort of acoustic refraction) are generating high ‘sound’ levels (remember, this is water so the acoustics work differently). The researchers appear to be using an impulse to generate reflections for their analysis - if there’s one thing I’ve learned over the past 10 years, it’s that impulse-based test methods have far too many problems. There must be a better way.
Bob Haas of Portland Oregon has posted some tips for amateur concert recording. I’m pointing out Bob’s page because he recently sent me some CD’s of classical concerts he recorded, and the music sounds gorgeous - he’s clearly doing something right.
The first surround sound Grammy was awarded a couple of weeks ago.
The American Motorcycle Association acknowledges that motorcycle noise is becoming a major issue nationwide. I’m glad to see that a motorcycle advocacy group is trying to reign in some of the excessive exhaust noise that some of its constituents insist on foisting on us.