Questions tagged [microphone]

A sensor converting an acoustic signal into an electric one.

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27
votes
2answers
12k views

What makes one microphone better than another, and how do I make my own?

I am curious about microphones and have a few questions. What is the key component in them which makes one better than another? What does it take to build a high quality microphone on my own? I'm ...
25
votes
5answers
6k views

Normal capacitor vs. audio capacitor

I'm building a power supply for old Schoeps CMT30F microphones. Standard condenser mic are 48V-powered nowadays, but these are 60s/70s Schoeps mic from RadioFrance/ORTF, customized at that time to be -...
18
votes
3answers
97k views

Using a microphone with an Arduino

EDIT: I have been investigating in this problem for quite some time. It turns out to be a way more difficult project than I thought and not something for beginners. This requires expensive hardware (...
14
votes
2answers
882 views

Digital data coming out of a cell phone headset mic?

I want to connect a sound board / mixing console / whatever-you-prefer-to-call-it to the headset jack of my Motorola Android phone. I know the typical TRRS pinout of Left/Right/Ground/Microphone, and ...
13
votes
2answers
7k views

Want a USB mini-microphone array. Is it possible?

I have been learning a lot about adaptive beam-forming, and have been mucking around with various sims in MATLAB, etc. But what better way to understand something - truly understand it - than to ...
12
votes
3answers
14k views

How do I get +5v for loud noise, 0v for silence from Electret Microphone (or other components)?

I have been asking a few questions here to get to a proper one, the initial questions I asked are linked to at the end. I used Fritzing to make up some schematics of my initial thoughts, but at the ...
12
votes
3answers
36k views

How to make a clean amplified microphone analog to digital conversion?

I've asked a couple of questions relating to this project the past couple of days, but I cant seem to put it all together. I hooked up an electret mic into an opamp and gave output to my arduino ...
11
votes
3answers
24k views

Electronic aspects of iPhone 3.5mm audio output

I am working for a while now on a small project of building an external mic for the iPhone to be hooked in parallel to headphones (via the 3.5 mm jack). Basically, I want to replace the iPhone's ...
10
votes
2answers
2k views

Using a microphone from the 1930s

I have an old Braun Cosmophon BMF2020 microphone at home, which I have long been wanting to use for good ol' fun. I have virtually no technical knowledge, so I am completely uncertain how to power ...
9
votes
2answers
3k views

Use of 100K ohm resistor along with 0.1uF capacitor?

In the circuit diagram below, why is there a 100KΩ resistor (NOT R2) connected to the capacitor? To my understanding the capacitor-resistor act as a high pass filter to block the DC offset of ...
9
votes
4answers
12k views

Can I use a PNP Transistor with an Electret Microphone to get an non-inverting output for my Arduino?

I'm looking to simply read the generic sound level from an Electret Microphone. I've seen a number of schematics with NPN transistors, that will provide an inverted output (~5V when quiet, ~0V when ...
8
votes
3answers
1k views

Does a pickup microphone work in space (vacuum)?

Of course in space there is no sound transmitted via air, so there is no air-borne sound, but there is structure borne sound. This sound can be recorded with a pickup microphone, but do pickup ...
8
votes
3answers
6k views

Electret Microphone preamplification - will it work for dynamic type microphone?

I'd like to use this diagram to pre-amplify a microphone signal in order to activate the analog input of my arduino (source: reconnsworld.com) Will it work with a dynamic microphone in place of an ...
8
votes
5answers
5k views

Generating a differential signal

I was given a small task (actually it's part of a much larger task) where the requirement is to generate a signal which looks like it came from a microphone. The following requirements needs to be ...
8
votes
3answers
5k views

How to connect mic on arduino, with opamp?

I'm trying to connect a contact mic to an arduino. My knowledge in electronics is sparse, so please bear with me. I got a couple of lm833n audio dual opamps, which I'd like to put to use. I'm still ...
8
votes
3answers
969 views

Why is the collector feedback bias popular in electret-mic preamp circuits?

I got some simple electret microphone modules and I've been experimenting with audio amplifiers. I googled to find some example circuits, and I found that most of them resemble the circuit above. I ...
8
votes
2answers
32k views

Connect speaker output to microphone input

What exactly is the difference between a microphone signal and a speaker signal? I want to make a simple cable to connect a PC speaker output to a microphone input. Does anyone have a good idea or ...
8
votes
1answer
2k views

Designing a cable for bidirectional communication between 2 iphones via TRRS (headphone jack)

I'm trying to design a cable that allows bidirectional communication between 2 iPhones, connecting into their TRRS jacks. I've made the cable but it is temperamental at best -- can anyone help me ...
7
votes
7answers
9k views

Can a comparator (LM393) be used as an amplifier?

I have seen modules for microphones (such as the one below) that use the LM393 and claim to have amplification. I have looked this part up and it is a comparator. I have read that op amps can be used ...
7
votes
5answers
23k views

Do electret condenser microphones require phantom power?

I was under the assumption that electret microphone capsules do not require any phantom power an can be connected in the same way dynamic microphone capsules can be, due to the fact that they contain ...
7
votes
2answers
520 views

100 ohm and noise

This is an image provided by JIm Dearden, in answer to the question Lots of noise in the microphone amplifier circuit when idle. I'd like to know how introducing a 100\$\Omega\$ resistor reduces noise....
7
votes
3answers
30k views

simple microphone - speaker circuit

This is my first time creating a circuit, so forgive my poor understanding. I am trying to create a simple intercom system with a 9v battery. I have an 8 ohm speaker and a standard microphone: (...
7
votes
5answers
6k views

Why does my electret microphone amplifying and filtering circuit output so much noise?

Background information I'm currently designing a input conditioning circuit that amplifies and filters a electret microphone signal in preparation for the signal to be processed by an ADC (analogue ...
7
votes
3answers
24k views

How to amplify electret microphone to range from 0-5V with bias of 2.5V?

I'm new to op amps and have tried many circuits but don't get the results I expect. I know I must do some math but I get so confused. I thought my question is really simple but it turns out it's not. ...
7
votes
2answers
7k views

Amplifying sound from a microphone

I have a small piezoelectric ultrasonic microphone (receiving signals of around 40 kHz). But the voltages it generates are too small to be read by my micro-controller's ADC. So I want to amplify the ...
6
votes
3answers
2k views

Does this amplifier work with 5V?

I'm using an Arduino to read an analog signal from an electret microphone. Here is the circuit: But I will be powering it with 5V from the Arduino, So would this work okay? Thanks!
6
votes
1answer
10k views

What is a reasonable ohmage measurement for a microphone on a PC headset?

I've taken apart my PC audio headset, because the microphone stopped working. This random website seems to imply that most microphones for PC headsets are "low impedance" between 150 and 300 ohms. ...
6
votes
5answers
13k views

Oscilloscope using laptop microphone input…is that possible?

Its possible to have an oscilloscope from the input of the sound card? I'm trying to log the states of a PIC32 pin (min: 0V, máx: 3.6). Is it possible to put that value on a 3.5" jack and, on the pc, ...
6
votes
5answers
10k views

Electret microphone: selecting a bias resistor

I have inherited a circuit from a colleague using a MAX4063 pre-amplifier and an electret microphone. It's almost identical to figure 4 from the preamp datasheet: But where that circuit has 2× 1 kΩ ...
6
votes
2answers
1k views

Will providing line-level signals into a mic input damage the recording device?

I've got a cell phone, gopro, and DSLR that I want to record audio into. I don't want to record audio into a separate device. The problem with analog mic-level (millivolt) signals is that they ...
5
votes
3answers
10k views

My simple audio amplifier circuit does not work

In previous experiments I've made circuits to transfer sound from electret microphone to a powered speaker. Now I'm doing my first experience with an Op-Amp to make the sound louder and to be able to ...
5
votes
1answer
6k views

Phantom Power supply for Electret mic

Will this circuit work to connect an lapel mic mic (expecting ~2.5v plugin/bias power) to an XLR input providing phantom power (I have a choice of 12 to 48v). I assume the lav mic has a typical ...
5
votes
4answers
11k views

How do I build a TRRS headphone jack with a jack that is detectable by an iPhone

I have a circuit and I am trying to integrate it with an iPhone via a TRRS headphone jack's microphone input. I have a generic TRRS cord and am trying to send a signal through it. However, the iPhone ...
5
votes
4answers
2k views

Microphone mute anti-pop circuit works but still picks up a little audio

I built a simple microphone mute circuit that appears to be pretty common. It mutes the mic without making a popping sound by shorting the connection through a capacitor. It works pretty well, but if ...
5
votes
3answers
2k views

How is microphone's frequency response determined

It seems this is the chicken and egg problem. To be able to determine the frequency response of a microphone one needs a speaker that has a known response. To be able to know the response of a speaker ...
5
votes
2answers
4k views

What is the reason for adding a buffer stage?

I was following this microphone and speaker circuit and I could follow mostly but got confused when the author introduces a DAC buffer. http://www.instructables.com/id/Arduino-Audio-Output/?ALLSTEPS ...
5
votes
2answers
1k views

Wired headset circuit

I'm trying to understand how mobile phone headsets work. I figured out that the electret mic gets supplied with 2.7V by the phone. Opening a headset revealed the following PCB: I looked and measured ...
5
votes
2answers
7k views

How do you tell the difference between speakers and microphones?

How do you tell the difference between speakers and microphones? I pulled the following two components out of an old cell phone and cannot tell them apart. Each have two metal contacts on the back.
5
votes
2answers
899 views

What is the purpose of the resistor connected across ultrasonic receiver terminals?

I have seen a few circuits where a resistor is connected across the positive and negative (grounded) terminals of an ultrasonic receiver. It seems to "stabilize" the received signal. I have attached ...
5
votes
1answer
2k views

Electret Microphone Preamp Circuit

The following electret microphone preamp circuit seems to work pretty well. My electret model is a little off because on the bread board R6 needs to be ~33k to get the output at 1/2 supply. Just a ...
5
votes
2answers
2k views

High to low impedance microphone

I'm a helicopter pilot. I'm thinking of buying a headset Bose A20. My problem is that the Bose headset comes with a high impedance microphone, but the helicopter I'm operating is using a low impedance ...
5
votes
1answer
118 views

Microphone Amplification

I am working on a project using a microphone/microcontroller combination to detect if a clap has occurred. Thus far, I am using the Electret Microphone Amplifier - MAX4466 with Adjustable Gain from ...
4
votes
1answer
675 views

Low-noise amplification of microphone signals, tubes or chips?

When trying to capture faint acoustic phenomena, are vacuum tube amplification designs superior to ICs? In this type of application sensitivity and low-noise amplification are the desired objectives. ...
4
votes
3answers
4k views

Smartphone microphone sensitivity

I'm working on a project including usage of several smartphone built-in microphones. However, I have no idea what sensitivity (e.g. mV/Pa) should I expect. I haven't came across any manufacturer's ...
4
votes
5answers
2k views

How would I condition the signal from an accelerometer for a microphone input?

I'm looking to measure vibrations using a 3-axis analogue accelerometer connected the the microphone input on a PC. Ideally I want to combine the 3 axis into one signal as I don't really care about ...
4
votes
2answers
4k views

Microprocessor schematic symbol

When drawing a circuit a resistor looks like this. How would a Microprocessor look? Microphone? Webcam?
4
votes
1answer
3k views

Replacing a condenser mic with a MEMS mic

I'm working on a black-box piece of electronics which has a cylindrical "condenser microphone" with a main body diameter of 4 mm and height of 1.5 mm I want to replace the condenser mic (black box) ...
4
votes
4answers
8k views

Why is microphone + opAmp + Arduino circuit not working?

I followed the mic + op-Amp part of this schematic exactly using an Lm386 chip: https://randomskk.net/projects/lightstrip/schematic.pdf and sent the output from the op-amp into a pin on an Arduino ...
4
votes
3answers
352 views

Best microphone picking up sound within a small room?

I've tried several Electret Condenser Microphones as input to a generic USB audio sound card: MO064202-4 MO064402-4 MO064402-5 All mics work great at close range (about 1 or 2 inches). However, none ...
4
votes
1answer
87 views

(Electret Microphone) Why is input taken from the capacitor?

Why is the input signal taken from the -ve side of the capacitor? I do understand that the resistor has been added for voltage divider. Is this actually for filtering purposes? Or is the capacitor ...