Sometimes we see these microphones that look like stethoscopes stuck on the body of acoustic guitars, but have we ever wondered what they are for and above all how they work?
The contact microphones, also called piezo, or piezoelectric, are a specific type of microphones that hear the vibrations of the audio through contact with solid objects.
These microphones are completely insensitive to the vibrations in the air but record only vibrations coming from the structure of a given object.
Piezos generate an electrical signal if compressed mechanically and compressed if crossed by a current.
They are generally very cheap and easy to self-build, used for miking acoustic instruments with an inner tube, but also exploited by noise artists to experiment with sounds.
Here is the best piezo microphone for guitar:
The contact microphones based on piezo materials are passive and very high impedance, which makes them very weak as output if we do not combine them with a preamp.
The most common type of piezo is a piezoelectric ceramic circle wrapped around a thin metal disc.
This central disk is positively charged while the bronze disk is negatively charged.
One of the joys of using contact microphones is their extended range of use but always remember that these need vibrant surfaces to function, whatever vibrates and resonates can be fine.
There are those who like to connect, for example, a piezo to the windows of the room where it is recorded to capture the nice vibrations of the glass and have an interesting room sound to add to the mix to make it deeper.
Often using a piezo microphone is a bit of a bet, in fact not all materials react in an interesting way, some will simply sound too deaf or rough, while others will give very special and musical tones. Never be afraid to experiment.
The piezo can be connected to everyday objects: bins, floor, scooters, cabinets, tables, books, chairs, walls, lamps, etc. etc. Attach your piezo here and there for some evidence, there are materials that are real surprises.
Record the guitar with a piezo microphone
Piezos are often used as an economic solution for recording guitars in live settings.
Live they are very comfortable because they react better to feedback on stage and are not influenced by the return of the surrounding instruments, however, they have the flaw of flattening the guitar sound a lot not reproducing the acoustic interaction of this with the outside world, but merely capturing only the mechanical vibrations given by the strings.
Piezos are often used in tandem with other microphones, adding the sound in mix to get an interesting timbre of the guitar, in fact they tend to make it sound a bit "fake" and metallic, with a lot of attack but going to lose practically all the dynamics.
If you don't know which piezo microphone to buy try this Adeline AD-35, I mounted it on a guitar and a ukulele that I have at home and the results are excellent, there is always the option to build it yourself but if you want to have a ready-to-use solution the Adeline is certainly a great alternative.
It has a warm and soft sound, which can also be used alone in emergency situations on stage.
The possibility of adjusting the volume directly on the device with a small knob is useful.
Here is another cheap piezoelectric microphone recommended by my friends, inveterate guitarists and sound engineers for famous Italian bands:
- FIT FOR: This pickup is suitable for most acoustic instruments, especially for guitar, ukulele, violin, cello, mandolin, etc. You will benefit from it.
- EASY TO USE: The guitar pickup is very convenient to use, it can be mounted on almost all acoustic instruments including guitars, violins, ukuleles, etc. You can easily connect it to your amplifier, bass amplifier or other recording equipment without damaging the instrument body.
Well, we have come to the end, friends.
The piezo is without a doubt a great microphone to experiment and become more aware of the environment around us.
Until next time!
Last update 2019-11-27 / Affiliate link / Images from Amazon Product Advertising API