Questions tagged [microphone]
A sensor converting an acoustic signal into an electric one.
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Why is voltage from sound card in audio circuit not constant?
I have a JLI2555 microphone capsule connected to a JFET Transistor that is then connected to a sound card that goes into the usb port of my laptop. The idea is that I want to record my voice using the ...
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Board Voice Recognition Module V3.1 with Arduino Uno [migrated]
I have two speech recognition modules and I am using vr_example_train from the voicerecognitionmodulev3.1 library. One of the VRM works perfectly, the other one train the voice command too, but when I ...
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Microphone pre-amplifier op-Amp outputs larger voltage when Mic RL is larger
I am following TI's pdf Non-inverting microphone pre-amplifier circuit with AOM-4544P-2-R microphone. I probe the circuit on the Vout after the op-amp, (not on the mic directly). I am playing around ...
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Audio Transformer with Center Tap to XLR Cable
I would like to put an isolation transformer at the differential output of MAX4063 chip.
This transformer has a center tap. Then at secondary side, outputs will be connected to a 3-pin XLR cable.
Is ...
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Can I use a contact microphone to detect a fan running / not running inside an electronic product?
I'm involved in thermal testing of an electronic product which contains a small centrifugal fan. The product is entirely sealed and no signals can be transmitted through the case when it's operating.
...
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Can I connect multiple different devices via a single I2S interface?
I am using a microcontroller with only one I2S interface. I am using MAX98357A which has 1 sound chip. There is 1 microphone, SPH0645. Can I connect these ICs to the same line provided that I cannot ...
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What should be preamp gain so output is at line level?
this is the MIC spec:
PREAMP I'm planning has a gain of 100:
I feel that gain of 100 is too much for a line level output.
What should be correct gain?
Thanks!
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Squelch Function - microphone preamplier
I would like to add a squelch function to this mic preamp:
EDIT: NE5534 pinout per SPICE model
Output should only be present when minimum input signal amplitude is reached. If I leave it as it is, ...
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Is there a risk of a DIY pre amp damaging a microphone?
I'm looking for a preamplifier to use with an aquarian A1S hydrophone. This is an application where signal integrity is not very important and we're going to filter and do a fourier transform on the ...
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Headphone amplifier for Camera without audio jack
I am thinking about a project for my camera.
A problem that often occurs with cameras and I haven't found a solution yet is, that there is an external microphone input but no audio output to monitor ...
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How can I connect an amplifier circuit to microphone input on a laptop?
I have a microphone TRS plug and want to connect it to a USB port on my laptop and the other end to an amplifier with a microphone connected to it. I have bought a soundcard to be able to connect the ...
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Electret microphone to headphone does not work
I would like to make a circuit that takes an electret microphone as an input and the output will be the sound recorded by the microphone with amplification.
I've built the circuit with one amplifier (...
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Convert a 5 pin Elno connector to a 3 pin XLR
I'm trying to modify a Elno laryngophone's connector (5 pin) to plug like a normal mic so I need to understand how to wire cable to a standard XLR connector, maybe somebody knows how to do? thank you
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Can I power 3.3V to MEMS mic which is TYP=1.8V?
I am reading this datasheet.
I have 3.3V for MCU and running out of space in the PCB area. So I want to avoid adding LDO for 1.8V.
In the datasheet, it said ...
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Low bias voltage from headphone jack
I want to connect my microphone capsule (JLI2555) to a headphone jack. I need a voltage to power the capsule from the microphone pin of the headphone jack cable but when I measure it with a voltmeter ...
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What is the correct sensor to use for capturing ambient noise?
I'm working on a project to capture ambient noise in my room (e.g. coming from the nearby vehicles, birds, etc.) for audio analysis (understand loudness/frequency characteristics). Problem is I'm ...
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How does this microphone preamplifier work?
This preamplifier circuit is designed by Andy Collinson for dynamic microphones. I can't understand how it works.
Why is the microphone input connected to the emitter of Q1 instead of the base?
...
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TRRS headphone and mic swapper
I'd like to create a serial cable link library between two devices called Playdates. They have a TRRS audio jack, and my idea is to use a few cables as shown below to connect each Playdate's audio out ...
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How to increase a mic output level?
I have an old lapel mic that outputs a signal that is way too small for most applications. In my attempts to learn electronics I started analyzing it and reading about the subjects. Still, I'm left ...
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How to boost microphone impedance and audio level
I have a microphone with an impedance of 194 ohms.
I want to be able to connect this to my smart phone via the CTIA standard.
In order to do that, I need the impedance of the microphone to be at a ...
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Loading effect of an op-amp as inverting amplifier
I have the following circuit, with an electret microphone and a TL082 op-amp:
I was asked to calculate the load effect of the amplifier. However, I don't understand: I thought that the whole point of ...
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Are there any certifications required when selling a home-made microphone in the EU?
If I am interested in selling a microphone I designed in the EU Market (for example on Amazon,) do I need any certifications for it?
I looked through some of the products that require the CE mark but ...
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Is my microphone capsule dead?
I am using a JLI2555 microphone capsule. I tried making a circuit to see if the microphone capsule works. The goal was to measure voltage fluctuations at the output with a voltmeter as I yell into the ...
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Have I connected the JLI2555 microphone capsule correctly in my circuit?
I am working on a DIY Project from this YouTube video. I have bought the JLI2555 microphone capsule but I haven't managed to get it to work.
I connected a JFET with the gate of the capsule and source ...
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What is the purpose of these passives in a microphone pre-amplifier circuit?
This is the typical application circuit of the MAX4466 "microphone preamplifier" op-amp.
Are these resistors/capacitors purely for generating a bias voltage? If so, aren't there much simpler ...
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Design an AGC circuit for microphone using JFET
At the beginning of the circuit, I designed a 20Hz to 20kHz second-order Butterworth bandpass filter circuit, and then I tried to pass the filtered signal through an AGC circuit to achieve a smooth ...
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Wiring a 2-pin K1 to a 3.5 mm jack with a mic and PTT?
Is there a possibility to wire a 2-pin K1 headset connector to a 3.5 mm jack with a mic and using an external button for PTT in order to close the PTT circuit? If so, please help me, I have been ...
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Mixing a microphone and a amplified speaker to a vlog set up
I have a BT motorbike head set and I want to take both the microphone and the audio from the ear price to the GoPro microphone jack..
Reason is we use this for recoding our vlogs and it’s good to get ...
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Understanding how a digital microphone's output gets stored in DSP memory
I am working with a DSP that takes audio input from a digital microphone. For the sake of this discussion all input sounds are pure sinewaves.
The DSP receives microphone data as 24-bit numbers. Let's ...
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Amplifying mic signal with instrumentation amplifier
I'm trying to amplify my dynamic microphone's (SM57, 1.6 mV OCV, 150 Ω) differential signal to about instrument pickup level (-20 dB) to drive effect pedals.
Currently, I'm testing with an AD620AN to ...
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Are all adapters for TRRS to TRS the same? [closed]
I want to connect an audio device (specifically, a phone) with a TRRS output port to a second device with a TRS microphone input (an audio recorder).
I tried one such adapter but it does not work.
I ...
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Why does the majority of the microphone current have to flow through R1 in this amplifier?
In this circuit:
Why does the part underlined in red matter? I don't understand, why do I want more current flowing through R1?
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Name and cause for phenomenon in microphone preamp output as seen on scope screen
What might cause 1 kHz sinusoidal signal to change such as seen on the screen? How is this phenomenon possibly called?
I have quite a lot of hand microphones with built-in opamp preamp and electret ...
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Raspberry Pi I2S speaker and microphones on the same connection
I am planning on buying an I2S speaker amplifier for my Raspberry Pi project. I already have the microphones for it. My question is whether the I2S interface can support speaker and mic at the same ...
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Building a dynamic microphone preamp
I'm looking to build a preamp for a dynamic microphone (SM57, rated at 150 Ω with -56 dBV/Pa). I've just finished a course in circuits and I'm having a bit of trouble approaching this design problem. ...
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ESP8266 analogRead() microphone input into playable audio
My goal is to record audio using an electret microphone hooked to an analog pin of an ESP8266 (12E) and then be able to play this audio on another device. This is my circuit:
In order to check the ...
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How to remove INMP441 MEMS microphone low-frequency noise
I have code that allows me to record I2S audio from the INMP441 MEMS microphone module using an ESP32. The data is read from the data out pin of the device.
When I take the Fourier transform of this ...
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What is the point of the connection to ground, with resistor, on the inverting output of this MEMS microphone?
For reference, the datasheet I am referring to in this post is given by this.
I was wondering whether anyone could clarify the point of connecting the inverting channel of the succeeding stages of the ...
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How can I use the same microphone for an amplifier and a mobile phone?
This is my first question on this forum, and I would like to say that I am learning electronics, and I am not an expert by any means.
I am currently trying to realize a small project using a LM386 to ...
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Help with finding the type of output for a mems mircophone
I am using this MEMS microphone for a stethoscope project. The data sheet recommends the following interface circuit.
I can't seem to find where it states specifically that it is a differential output ...
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Unable to get any kind of audio from I2S INMP441 omnidirectional microphone on ESP32 devboard
I am trying to get an I2S INMP441 omnidirectional microphone module to interface with an ESP32 devboard. I have been unable to get any kind of information from it. I have tried multiple ESP32s and ...
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In which direction is the microphone signal transported?
So I understand the general principle of how the audio signal is transported. I also understand that audio signals can be distinguish between AC and DC.
But let's say we have a TRRS Jack like below. I ...
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Push to talk mic over music
I have an amplified mic and I want to mix it with an mp3 player output. I tried something like this without a relay (just a button with 2 pairs of contacts), but I hear a pop when I press the button (...
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Is my understanding of the electret microphone correct?
I've been trying for a few days to understand how an electret microphone with two pins works.
What I think I understand is:
The microphone has inside its capsule a capacitor that changes its ...
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How to increase sensitivity of sound sensor?
I'm using a sound sensor, hooked up to an ESP32, to determine whether a medium-sized pump is running or not.
While this works well when the pump is running loudly, it works less well when the pump is ...
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How can I improve my 20m transceiver microphone amplifier?
After weeks (on and off admittedly) of debugging, I finally figured out why my homebrew 20m transceiver was oscillating on transmit.
Despite all attempts to improve grounding (I have a single copper ...
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DAQ sound acquisition
I have a simple USB DAQ device (datasheet). I was hoping that with differential voltage I would be able to measure simple sounds and convert/store them as a simple audio file (e.g. WAV, MP3). I see ...
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Vibration and noise pickup from a "quiet" machine base
I am trying to do a noise/vibration profile on a piece of machinery in an incubator. Ideally, it should not be subject to vibration, but inevitably there will be some.
In addition to the internal ...
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Can improper loading (receiver/preamp with too low impedance) of a dynamic microphone cause magnetic damping in the moving coil?
Reading about impedance-bridging in mic signal amplification got me thinking about this (please correct me if I'm deeply misunderstanding some fundamental concepts here)...
A dynamic microphone is ...
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Computer microphone disconnects when connected to wave generator
I am using the Visual Analyser virtual oscilloscope as both an oscilloscope and a wave generator (on two different computers). I connected audio jacks (1 TRS and 1 TRRS) to a breadboard to connect the ...
