A sensor converting an acoustic signal into an electric one.

learn more… | top users | synonyms

0
votes
0answers
45 views

Decode an infrared signal with an IR demodulator inside a microphone jack

I was looking at this tutorial about how to decode an infrared signal. One of the posts says For the scoped challenged (like me), a PC microphone jack works great for reverse engineering IR ...
-2
votes
0answers
32 views

microphone input to android phone [on hold]

I have a Huawei phone I’m using to measure AC voltages. I have a 10k and 1k resistor across the voltage I am trying to measure and the microphone and ground of the jack to the phone input is across ...
1
vote
0answers
27 views

Connect electret mics to computer [closed]

I'm trying to do cross correlation on the signals arriving at a microphone pair. I do not want to record anything. Before doing this on a development board (like the beaglebone/board), I decided to ...
0
votes
0answers
20 views

Problems sending mic input to IC preamp

I am using the following product: http://datasheets.maximintegrated.com/en/ds/MAX98089EVKIT_TQFN.pdf It is an audio codec eval board with RCA input jacks. They provide software for setting all ...
2
votes
4answers
288 views

Calculating Wavelength of sound using an Arduino

I'm using an Arduino Uno R3. I need to measure the wavelength of sound of a particular (known) frequency. By substituting in the equation: Vsound = Frequency * Wavelength ...I wish to calculate the ...
3
votes
0answers
48 views

Modifying headset's microphone to hear from it? [closed]

Problem? I have a headset with a microphone, like this: Good for you. What do you want? I want to use my headset's microphone as a real microphone. It's already a real microphone, you noob. ...
1
vote
1answer
44 views

Reading analog sensor as a microphone signal (via sound card)

I was thinking and studying on how an analog-digital-converter works and just realised that the sound card of every computer-devices is exactly that one. My question is: how can I read an analog ...
1
vote
2answers
46 views

How does internal capacitance affect an electret microphone?

I'm evaluating two different high sensitivity, low frequency microphones from the same manufacturer. They are the same part with a differing internal capacitor, but I'm not provided an internal ...
1
vote
1answer
54 views

Help Identifying SMD Microphone

I suspect this component to be a SMD microphone made by ST. Unfortunately I could not map the writings on the device to any SMD microphone datasheet issued by ST. Do you have a clue?
0
votes
1answer
72 views

Microphone output resistance, why this value?

I would like to sample the output of a microphone. I am using the following set-up in order to tune the DC offset at the microphone output. simulate this circuit – Schematic created ...
0
votes
1answer
133 views

How to connect a microphone to apply audio signal to electronic circuit?

I am working on a project where we have to design a band pass filter signals in audio frequency range. We have tested the filter design using Signal generator already, and now we want to see if it ...
1
vote
0answers
169 views

Connect microphone to RN-52 Bluetooth module

My goal is to build a bluetooth hands free device, basically a speaker phone, to pair with a mobile phone. I am using the Roving Networks RN-52 Bluetooth Audio module mounted on a breakout board from ...
1
vote
1answer
65 views

How to test a capacitive microphone

How can I test a mini capacitive microphone? I have a mini microphone(something used in telephones) and I want to create a circuit to see how it works? I want to speak to it and see how current or ...
2
votes
1answer
204 views

Electret microphone amplifer for general aviation

I'm attempting to create a converter box that allows the use of a standard electret mic and earphones as a headset for general aviation. The headset is relatively straight forward, just use an audio ...
0
votes
1answer
39 views

Replacing a built-in microphone?

This question might fall under the "if you have to ask" umbrella, but I have a set of bluetooth headphones that I think would perform a lot better if it was on an arm instead of being built into the ...
1
vote
1answer
67 views

Power a circuit and read output from tablet microphone port

I have a project that I'm currently powering with a AAA battery, providing 1.5v to a simple 555 timer circuit. The output of the circuit goes through a voltage divider into the microphone input of a ...
1
vote
1answer
94 views

Vibration Sensor

I would like to make a vibration sensor but the surface is moving around a lot and the sensor might be displaced due to said movement, friction etc. One way to do this is using a microphone over a ...
2
votes
1answer
49 views

How do I get high-performance guitar microphone going for cheap?

Main question: Can I use a lot of cheap microphones off digikey and combine the signals somehow and will this make it sound like a higher-end mic? How do you shop for a microphone: what specs are ...
0
votes
1answer
42 views

Connect in-built microphone in webcam through USB [closed]

I recently repurposed a webcam from a HP laptop to make it USB webcam. I was able to connect the webcam to USB. It also has an in-built microphone, and I dont know how to make it usable. The webcam ...
2
votes
1answer
89 views

Join the microphone and audio lines from a headset for recording

Question What are the steps required to join the microphone and audio lines from a typical cell phone headset into one line so that the audio can be recorded by a standard voice recorder using the ...
3
votes
0answers
140 views

passive high pass filter to iphone mic jack

I'm attempting to input a heart rate signal into my iPhone via the microphone jack. I need to pass the signal through a passive high-pass filter to remove the DC offset before inputting it in to the ...
0
votes
1answer
89 views

4 pin headset pinout / pushbuttons interface [duplicate]

You all know smartphone headsets. Most of them have a microphone integrated and additional pushbuttons for increasing/decreasing the volume or to pause the current track. I am wondering how this is ...
0
votes
0answers
82 views

iPhone TRRS Circuit Not Working

So basically what I am doing is creating an FSK module that sends data to the iPhone via a 4 pin headphone connector (TRRS). So the FSK audio signal comes from the module, and into the mic pin of the ...
3
votes
1answer
223 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 ...
2
votes
1answer
101 views

Calculate the appropriate bias voltage (and resistor) of a condenser microphone

I have a condenser microphone that has no any model name or number. As we know condenser microphones need a bias voltage for operation. Some microphones need \$2 V\$[1]. and some need more. As we can ...
0
votes
1answer
95 views

Headset with microphone effect on smartphone battery life

I am building a device that will connect to an Android smartphone 3.5mm jack and was wondering if my device would drain the battery. When checking the current on the microphone line on headset ...
0
votes
1answer
143 views

Detecting location of infrasound noise in a building

I am working in a large office building with a lot of people. Pretty frequently there is a very weak and low frequency noise that is very irritating. Unfortunately, I have found just one other person ...
0
votes
0answers
52 views

What do the numbers in the output a microphone mean?

I have written a code in python that plots the built-in microphone's output (at the sample rate 44,100). I see that the output is an array of numbers. What do these numbers mean. My guess is that they ...
1
vote
2answers
169 views

Boost converter noise

I'm trying to prototype a hobby project on a breadbaord. I'm using an electret microphone + opamp to feed MCU ADC with audio signal. When I'm using a regulated power supply I get good signal with ...
3
votes
3answers
981 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: My ...
1
vote
0answers
192 views

Connecting a geophone to Arduino

Simple question: I want to connect my geophone to an Arduino input. The geophone I have is actually output to a microphone jack and I can plug it directly into my computer. I'm pretty sure I can treat ...
-2
votes
1answer
83 views

Micro-controller and microphone minimal current possible

We would like to have an idea about the minimal current consumption that could be achieve. We need to have some microchip mcu, that have a microphone connected to its ADC port, and that is always ...
1
vote
2answers
111 views

Mic pre-amp hum

I've designed a very simple microphone pre-amp to use with my headphones. The thing is I get this 100Hz hum in the output. Is it because I should've used a voltage regulator? Here's what the VRipple ...
1
vote
1answer
321 views

How can I attach a microphone and speaker to the Arduino GSM shield?

I recently purchased the Arduino GSM shield so that I could build my own low-tech cellphone. Now that I've successfully been able to send and receive text messages, I would like to add the ability to ...
3
votes
1answer
131 views

Circuit simulator with microphone support

I am working with a circuit that consists of a condenser microphone. The circuit will filter through all sound signals except very sharp high pitch sound. But I cannot find any circuit simulator that ...
4
votes
2answers
102 views

Why need more aperatures in microphone array?

I am tring to achieve delay sum beamforming with microphone array, for that I bought playstation eye camera which has 4 microphones in it. For locationg the angle of the sound I need to find exact ...
3
votes
3answers
256 views

What do these passive components do in this microphone amplifier circuit?

I have this circuit I built long ago to amplify 2mV signal from speaker and phase shift it by 2.5V. Now the question is, what does C2, C4, R5, and R6 exactly do?
1
vote
1answer
60 views

Microphone time delay estimation

I'm trying to estimate the direction of arrival of sound using a microphone array. This requires me to find the delay of the sound signal upon arriving the different microphones. For convenience, I ...
4
votes
2answers
221 views

Which low voltage single supply opamp for ultrasound mic?

I have a problem choosing right opamp to amplify signal from 10KHz-65KHz mic SPM0204UD5. According to microphone's datasheet, it has max output impedance of 300Ω, and supply voltage from 1.5 to 3.6 V. ...
4
votes
3answers
492 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 1kohm ...
1
vote
2answers
236 views

Linkwitz mic preamp mod

I build and measure loudspeakers at home as a hobby. But I have never had a decent mic preamp for my unmodified Panasonic ECM capsules. I use a USB sound card to accept the mic audio and analyze it ...
-3
votes
2answers
1k views

4 pole 3.5mm audio cable to a single pole compatibility [closed]

A very simple question. I just want to understand how a 4 pole TRRS jack works. Say I have a 4 pole extension cable (male-female) that Id like to use with a mic on one end and the other end to ...
2
votes
4answers
241 views

Detection of weak periodical sound signal having negative SNR (will lock-in-amplifier be useful)

I'm trying to understand whether it is possible to detect human's heartbeat from a distance. I'm not a specialist, but it seems to me that the following issues must be addressed: Very sensitive ...
7
votes
2answers
199 views

100 ohm and noise

This is an image provided by Jim Dearden. I'd like to know how introducing 100 ohm resistor reduces noise. If I short that 100 ohm resistor then the noise is increased significantly whereas if I put ...
0
votes
1answer
231 views

Lots of noise in the microphone amplifier circuit when idle

I come again to get help from the experts. I am using this BJT transistor in the circuit. http://www.fairchildsemi.com/ds/2N/2N3904.pdf Here is the microphone that I am hooking up in the circuit. ...
3
votes
2answers
194 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 ...
1
vote
2answers
542 views

How can I integrate microphone and speaker into my microcontroller project?

Having never worked with mic and speakers in the past, I am experimenting with these. I already made a simple circuit with a mic (electret condenser microphone) and speaker. I used the above mic with ...
3
votes
2answers
311 views

matching input and output impedance in an audio circuit

I have searched many places but have failed to get a clear and convincing explanation about why we match input and output impedance in audio circuits. For example: lets consider a simple audio circuit ...
0
votes
2answers
118 views

Impedance of a microphone?

i am referring to this datasheet http://www.cui.com/product/resource/cma-4544pf-w.pdf As you can see, there is extra circuity needed apart from the microphone. One thing i don't understand is the ...
1
vote
1answer
94 views

Measuring the mic signal of a computer headset

my colleague and me have hit a brick wall - and are hoping somebody can help us out here :) Following scenario: We record some data using a computer with an NI card and some signal transducers. We ...