Questions tagged [audio]
Questions about designing electronics for measuring, processing, and amplifying audio signals.
436
questions with no upvoted or accepted answers
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Amplify Raspberry Pi Zero's audio with '60s tube amplifier circuit
I have been restoring some old '50s and '60s tube amplified radios, fitting them with Bluetooth while maintaining the original electronics and functionalities.
I achieved this by connecting the ...
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4
votes
1
answer
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How to properly couple DC in this biased headphone amplifier design on power-up?
I am a self-study noob to electronics (and audio electronics) but diligently learning every day :) Some things I understand well, others I'm fuzzy on.
This device is a headphone amplifier using NE5532 ...
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Is it mandatory to isolate D+/D- to clean my noisy MIDI power supply
I designed a Piano controller with MIDI synthesizer board which works pretty well but there's noise in the jack output. All my board is supplied by the USB (a typical type B connector).
I searched ...
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Designing an audio amplifier, problems with bandpass filter
I am trying to build a Audio amplifier for a university project, I think that most of my circuit is done but I have an issue with my filter as my sine signal is not symmetrical after filtering to ...
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Can I connect a MEMS mic directly to this spectrum analyzer chip?
I have a ICS-40181 MEMS mic and want to do basic spectral analysis using the popular MSGEQ7 chip for the purpose of a sound reactive project.
Can I simply connect one into the other (with cap/res as ...
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Modded speakers emit high frequency noise, how to filter it out?
I came up with an idea to convert my PC speakers into Bluetooth speakers. It's not really a serious project, rather a proof of concept, but I want to get it to work as well as possible.
Here's my ...
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2
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TRS differential input and output connector wiring for balanced audio CODEC I/O connections
I've been studying the ADAU1361 evaluation board and noticed an odd thing how the differential input and output connectors are connected in their schematic on its user guide, page 7, focus on the left ...
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How to Switch DSP to Passive Speaker Driver?
I am working on an Active Noise Reduction project for a headset using Codec ADAU1772 from AD. There are two inputs, one of which is feedback mic. connected to AIN0, second is INT+ (Intercom or music) ...
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How to light LED with (Phone-)Audio signal for Vactrol
i'm an eager electronics noob, so sorry if this is a dumb question...
I'm trying to build vactrols controlled by audio signals to control other circuits.
So far this configuration with a 2n5457
seems ...
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2
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LM386 driving transformer going into oscillation
I have a transformer on the output of a LM386. The circuit works just fine with 42TU003-RC, but when I use any other transformer the circuit goes into osillation at ~350 kHz on the output of the LM386....
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Use TRS jack as Mono + 5V power input
I'm trying to change this guitar wireless transmitter so that the audio input jack also becomes a charging/power source.
The charger will be a separate box with "stereo" input socket.
...
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2
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Help understanding audio interference from laptop when using UPS device
I have no Electrical engineering experience and would appreciate a layman's explanation on what my issue is (if possible).
My laptop battery became swollen a few months back so I removed it and have ...
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2
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687
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Active low pass filter built around an LM386
I have some theoretical electronics knowledge from uni, but when it comes to applying it in practice, things can get a little bit complicated.
I've built simple stomp box, basically a piezo transducer ...
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2
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TRRS 3.5mm audio jack wiring to sim868
I want to connect a 3.5mm trrs audio connector to sim868.
The image above is my connector.
But sim868 has four pins as:
1- MIC +
2- MIC -
3- SPK-N
4- SPK-P
As shown in the picture above, the pins of ...
2
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0
answers
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Overtones(?) seem to be showing up in FFT of audio signal
I am processing audio data using a Teensy 3.2. I have a microphone attached to it, and am playing music in my room using some powerful speakers.
When I look at data from the Fourier Transform of the ...
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Audio mixer on battery power
I have an audio mixer which can run on two 9V batteries in series. I'd like to run it off a single 12V supply.
Can I use two 12V-9V DC-DC converters both running off a 12V battery?
Will the ...
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How to connect 5 colored wire headphone to 3.5 TRS jack?
I have a somictone headphone and I want to repair its headphone jack, It contains five colored wires.
Here are the wire and TRS jack.
Please give me a feedback
Can you please tell me how to wire this?...
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3
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110
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Are these 2 circuits interchangeble?
I found the upper circuit. Originally it is designed as an output circuit for an audio player with a jack output. I have no transistora lying around, but opamps like the TL074.
I made the lower design....
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Summing Audio Channels
I’m trying to sum my car stereo output. Factory output has bass on one output and mid and tweeter on another output giving me 2 channels for left and 2 channels for right.
Ideally I’d like to sum ...
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Strange leak problem in simple tone control circuit
I built the following circuit (physically):
V1 is my audio signal and the circuit is a simple tone and volume control. When both the volume and the tone pot are turned all the way down (so each wiper ...
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Simple MM Phono Preamp Design
I'v found myself in need of a new preamp for my turntable (the one built into my power-amp went out with a bang and tripped the breaker!).
I'm using a moving magnet type cartridge with output around ...
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Cmedia CM118B USB Audio chip datasheet lacks application schematics. Has anyone experience using this or similar Cmedia chips?
I'd really like to use the Cmedia CM118B USB audio chip - it's dual ADC and DAC, so supports stereo speakers/headphones and stereo mic over USB. However, the datasheet lacks any application schematics ...
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How to connect Electret Microphone module and OPAMP?
I am trying to build a circuit that gets electret microphone input and maps into 0-1V for utilizing in ADC.
The microphone module suggests using such circuitry
When I tried that circuit and talked ...
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Can I make this Bluetooth speaker stop cutting off its speakers when audio signal goes silent?
I have a simple Bluetooth speaker that always seem to cut off its speaker circuit when the audio stream goes silent. This makes an audible popping noise, which is repeated when the stream starts ...
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2
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1
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518
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CSR8645 3.2 bluetooth module audio output merge negative pins
I want to use this module with my car aux in which is has 3.5mm 3 pole jack. This module has separate negative pins as LN and RN. I need to merge and connect these pins to aux in common negative pin.
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Getting noise when connecting speaker out of SIM800l to Raspberry Pi
I was trying to make a roaming device which helps me route my calls through the internet, to save on my bills while on international roaming.
My setup is like this:
GSM module SIM800l, Raspberry Pi 4, ...
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139
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High SNR FM demodulation
So I need to demodulate the FM signal from a sensor with highest SNR possible, at least 70-75 dB. IF is 10.7 MHz, max. deviation is 200 kHz but I can change those values if needed. Baseband signal ...
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2
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How to connect a MEMS Microphone Breakout - INMP401 to a RN-52 bluetooth module?
I intended to use a INMP401 (MEMS MIC) to capture audio and stream it via bluetooth using an RN-52 bluetooth module (RN-52). The RN-52 has inputs for differential +- signals.
The INMP outputs ...
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2
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1
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Can anybody help me modifying a reverb circuit on a guitar amp to an FX loop circuit?
I have a solid state guitar amplifier with a reverb tank. I have done a bit of research as to how these work. I now want to replace the reverb tank with an FX loop for normal pedals (instrument level)....
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0
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80
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Audio Sampling for Reactive Lighting
I'm trying to work on a reactive lighting project and I'm confused about a couple topics when it comes to sampling audio.
I want to be able to have RGB reactive lighting controlled by a ...
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2
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0
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460
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Op-amp circuit saturates to negative rail and only passes positive side of input
I've been working on a spring reverb driver circuit, based mostly on figure 5 from this site: https://sound-au.com/articles/reverb.htm. While there's lots of information on the how of the circuit, ...
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510
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Dual antiphase electret mic preamp topology
I am currently trying to make a preamp for an electret mic pair, which are placed physically in antiphase. The main idea is to subtract one mic's signal from another and therefore boost the signal ...
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Why do some audio amplifiers connect the power ground to the signal ground?
Trying to add a MIDI synthesizer & speakers to a keyboard here. Here's the schematic:
simulate this circuit – Schematic created using CircuitLab
But I was getting annoying crackling and ...
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1
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475
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PCM1789 DAC direct connection to TPA6138A2 headphone amplifier?
Is it possible to directly connect PCM1789 DAC to TPA6138A2 headphone amplifier?
According to datasheet PCM1789 output are differential outputs and the input of TPA6138A2 is also differential inputs. ...
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413
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How do I wire a Shure WL 185 to to iPhone or iPad?
I have this old but very nice mic. Old days I recorded audio to the camera or recorder. Nowadays I record to iPhone so I do not have extra recording device and cameras are action cameras usually ...
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1k
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HTC 10 DAC/amp specifications
I'm going to be doing a final year project revolving around music production and DACs are pretty important. Not going to go into detail (unless this question requires it) what the project is but I ...
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Audio: Camera activated external microphone
I want to build a relay circuit that turns on an external microphone (powered by an internal 9V battery) when a connected camera is turned on (a camera offering only 1V plugin power through a 3.5 mm ...
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2k
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Noise-cancelling headphone concept
Inexpensive noise-cancelling headphones use a single microphone located in a little lump between the plug and the earphones. They seem to work fairly well for ambient noises, but not for handling ...
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Linear vs. Audio Taper for RC Network
I'm building a distortion pedal and I was wondering which tapers to use for which potentiometers in the tone control section. I normally design my own circuits, but I'm going by someone else's ...
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306
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Troubleshooting audio output on Nexys 2 (FPGA)
I've recently purchased the PMOD AMP1 module from digilent for use with my Nexys 2.
When I program the demo project and plug headphones or speakers on the headphone output I can hear a barely audible,...
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USB battery charger noise in an audio amplifier
As the title says, I'm having some issues with battery charger noise and an audio amplifier.
The PCB with the charger and amplifier is connected to a GSM device, and that's where the audio signal for ...
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Convert a wired headset to a wireless one
new to the board and not caught up with current technology, but I can handle myself when it comes to soldering and small electrical appliances. I have a headset that I really love, but the wire ...
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IRDA Through Audio Jack
I'd like to know if it is theoretically and/or practically possible to enable a smartphone (iOS or Android) to communicate with another device via IrDA (IrCOMM) using a simple infrared transceiver ...
user30575
2
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2
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997
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Unstability with TDA2002 bridge configuration
I'm trying, for MONTHS (obviously not everyday, but I spent at least more than 80 hours on this) to do a 15 W audio amplifier with two TDA 2002's in a bridge configuration, following the circuit ...
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1
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How does the center tap terminal work in Knowles Speakers ED series?
I would like to understand how the center tap terminal work in miniature speakers. I can see in the datasheet that a positive going voltage relative to this center tap can lower the output volume but ...
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Wiring 2 audio output transfomer secondaries in series or parallel
I want to know if wiring 2 audio output secondaries in series is doable. See problems with this schem? Would parallel be a viable alternative?
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RF signal on Audio/Music/Guitar equipment
It is looking like the standard RF noise from my (new to me) old apartment wiring through my amp to my speakers. Suspected it could be due to poor guitar shielding/grounding, bad cables etc. Started ...
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Inrush current limiter thermistor acting up
One of the power amps I am working on uses a thermistor for inrush current limiting (SL15 25003) as shown in the schematic below (ICL1). When I was testing the unit it seemed to me that there was some ...
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What is SAI frame synchro?
The SAI interface, as used by ST and others, includes some options which I have not been able to find any explanation of. Justme's answer provides a great explanation of frame, slot, and data size; I'...
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Which signal should be fed into the single ended input of the PAM8320?
I'm feeding audio from this DY-SV17F module into this PAM8320 amplifier.
The configurations I believe I can choose from are:
1: Feed either DACL or DACR from the module to the amplifier.
2: Combine ...
