- Dynamic microphones
- These are magnet based. They work a bit like a speaker in reverse (in fact, a speaker can operate as a microphone).
- Bigger cousin to the electret microphone. The cartridge size most effects sensitivity and noise. They often require phantom power to drive the microphone and to power a small preamplifier right at the microphone.
Condenser, Electret, Capacitive microphones
Most consumer grade electret microphone capsules are tiny, often less than 10 mm. The size of the diaphragm in the capsule makes a huge difference in the sensitivity and isolation from noise . A bit of searching will turn up large diaphragm condenser microphone capsule that are double or triple in diameter of the common, crappy nones. These work much better. They can be hard to find at first glance because the tiny <10mm mic capsules are so ubiquitous that it makes sorting for the mid-range capsules difficult. Look for diaphragms over 20mm.
- ZRAMO 34mm
- 34mm diaphragm for $20.
- Voxida CM012
- 25mm diaphragm for about $10.
- Transound TSB-2555B
- I believe these are no longer manufactured. This is a popular mid-range capsule. The capsule is 26 mm with a diaphragm of 21 mm. They sell for about $50.
- micparts caters to DIY hobbyists who build their own microphones.
- Audio Improv has lots of useful information on microphones as well as other audio topics.
- JLI Electronics sells microphone circuitry and components including many larger diaphragm condensers.
- Microphone research shows the dismantling of Transound capsules.
- Group DIY has lots of electronics and engineering info, including topics on microphones and preamplifiers.
- Creative Field Recording has info about microphones and low-noise recording techniques and tools.
- Wild Mountain Echoes has info about recording nature sounds, including ultrasound.
- Avisoft Bioacoustics sells ultrasound microphones and analysis software.
- Audubon -- A Beginner’s Guide to Recording Bird Vocalizations
- PUI Audio
These act very much like a radio dish antenna works. A parabolic disk captures sound and directs it toward a microphone. This also adds a highly directional sensitivity to the setup. Parabolic dishes are often sold paired with microphones, but an end-user may opt to purchase only a dish and add their own microphone.
Wildtronics makes parabolic dish microphones.
amplifiers / preamplifiers
- 3 fA Input Bias Current CMOS Op amp
- Ultra-Low Input Bias Current Instrumentation Amplifier
- AD743 / AD745
- FET input op amp. ultralow noise.
- OPA627 / OPA637
- FET input ultralow noise.
- low noise audio op amp with RIAA response. Bipolar, so it is not ideal to start new projects with, but it's well known and you will bump into it often.