#MusicMonday: Expert Advice on ‘Microphone Levels & Pressure Zone Mics’ | #audiophile
Good, quick read from EDN on PZMs – possibly how impulse responses are designed, although I’m still piecing together the theory behind it all let alone the real-world applications.
Many engineers and audio people don’t realize just how much signal can come out of a microphone. A hot mic with large signal can output many volts. That a dynamic microphone does this with a 120 ohm impedance is all the more remarkable (Figure 1). My pal, audio guru Steve Williams, recalled an entry in the Ampex Audio Digest bulletin board system (BBS):
“The circa 1968 demo for those who didn’t understand how much level could come out of a microphone (like those who were still trying to do rock-n-roll with Altec 1567 mixers with no input attenuators): Take your Simpson 260. Set it on the 2.5 VAC range, and connect it to the output pins of a Shure vocal mic. Hand the mic to someone with a good set of lungs, and have them do a good rock-n-roll scream. I never saw anyone pin the meter at 2.5 volts, but 1.5 volts was easily achieved.” anon
Figure 1 This plot shows microphone levels of a speaking voice can easily reach 0.1 volts. Shouts, screams, or loud music can be 20 times greater. (Source: Clifton Laboratories)
8-6-2021 (August 6, 2021) is the Snakiest day of the year and it’s also this year’s CircuitPython Day! The day highlights all things CircuitPython and Python on Hardware. See you there!
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.