Questions tagged [audio]
Questions about designing electronics for measuring, processing, and amplifying audio signals.
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Designing a circuit with a LM386 amplifier
I'm designing a circuit an I want to use the LM386 audio amplifier. Before designing, I'm going through the whole datasheet, I've seen that VI is from -0.4V to 0.4V :
Here is the first typical ...
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Bluetooth headphone volume, play, pause, skip commands [closed]
I'm building a bluetooth audio transmitter to send audio to a pair of bluetooth headphones. Simple enough using any number of available bluetooth boards on amazon, ebay or aliexpress.
Such as this
But ...
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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 ...
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How do I calculate or estimate how long a battery operated circuit will power an audio exciter?
I understand that this question has a lot of moving parts to it and I am quite a noob.
I have a battery operated circuit which in turn powers a planar audio exciter (such as this one: https://www....
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Troubleshooting audio matrix power feed to PCB [closed]
I have faulty Control4 Audio 16x16 matrix. I have checked basically most of common components on pcb board and all looking good. Power supply also all good 5V DC. But when power supply is connected to ...
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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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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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Suggestions for Improving this Pre-amp Circuit
I made this preamp circuit for a dynamic mic and am mostly happy with it, but I'd love to get suggestions on how to make it a little better. I'd like it to have as little coloration as possible, and ...
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Potentiometers for vocal mics
I want to mute the output of a wired headset mic so that when the power pack is turned on it doesn’t make a pop through the PA. I bought this little passive volume control, but with the volume fully ...
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Minimizing small signal relay bypass pop
Attached is a stripped down version of the circuit. The relay is controlled by a push button going to a microprocessor then powered by a BJT with a flyback diode in parallel.
The output of the DSP/etc....
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What is an efficient way for distributing equal power to multiple audio amps?
I'm working on an audio system prototype that requires cables passing through active speakers in series. As cables will have different lengths, I'm counting on voltage drops along the way. Is there an ...
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OpAmp circuit modification feedback loop
I am somewhat a noob with electronics. I do understand some stuff to an extent and can follow logic but this goes beyond my full understanding.
I have an audio system that I would like to modify in ...
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How to correctly play sine wave sound?
UPDATE: following @brhans and @Audioguru 's suggestion I tried LM386 and it worked perfectly.
I'm working on a small project. The high level structure is, the MCU (RPi Pico) outputs PWM sound signals, ...
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Placement of filter capacitors in a circuit with multiple audio outputs
I have a multiple output stage of an audio circuit as in the picture attached.
I want to add a capacitor to eventually filter any DC at the output, therefore I placed a RC filter 10uF/100k(0,16 HZ) ...
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Interfacting a device's PCM output with a RPi?
I am planning to use a SIM7080G for a future project. However, I am facing an issue with the way it handles audio.
The SIM7080G has a PCM interface, which, according to the hardware design guide, is ...
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Single-Supply OpAmp design
I am trying to come up with an amplifier that can amplify an input audio signal about 4-5 times. This is my first time designing an amplifier, so please bear with me.
The circuit must operate on a ...
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Can the differential output signal of a DAC be AC coupled directly to the differential input pins of a class D audio amplifier?
The datasheet of the audio codec I'm using (CS4272-CZZ) suggest a filter on the differential output pins. Their suggested configuration also combines the signals into a single ended output. I want to ...
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DfPlayer Mini not working when using three LR44 batteries
I'm working on a small project that plays audio. This project uses an ATtiny85 and a DFPlayer Mini as well as some other small components to make the whole thing work. I've tested the circuit using an ...
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SIM800L GSM module humming noise
I am trying to play audio over the call by using SIM800l
I am using this "DFPlayer mp3 module" to play audio and connected its AUDIO OUT to the MIC IN of "SIM800L GSM module" and I ...
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Indentifying a JL chip marked 'EE4222-1BB'
I'm new to electronics and my Bluetooth speaker broke and I want to fix it. This is the chip I think I need to replace.
Can you help me identify this IC marked 'EE4222-1BB'?
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Use a single push button in two different circuits with different voltages
I recently assembled a multiple switch formed by some resistors and 3 push buttons (NO) to drive an audio effect for guitar (which I will call effect 1), this switch is passive and receives current (...
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Grounding and Ground Pour
I’m trying to build my first audio amplifier and need some help and advice on this topic.
It will be a simple 100 W audio amplifier, powered by +35 VDC and -35 VDC. There will be local power ...
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Increase Input Impedance for Guitar Pedal
I'm designing a guitar pedal circuit. I've received feedback that my input impedance is way too low in regards to my output impedance and I was wondering how I could go about increasing it.
To keep ...
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Fine-Tuning a Circuit After changing VCA (SSM2641 to SSI2164)
A friend's accident led to a fried SSM2641 VCA in an Eurorack audio module. Determined to give it a new lease on life, I'm diving in, though VCAs are not my forte.
After searching for hours, it seems ...
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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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Old Zener diode codes
I am trying to identify another Zener diode from a wem pa 100 pre amp, there is no spec on any of the various schematics I have seen, or to think of it there is never any on any WEM schematic for any ...
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Audio Crossfade MN Taper-like solution
I'm trying to find a solution for the following problem:
I have a RETURN section of a circuit that has to mix a DRY and a WET audio signals.
The circuit is Stereo.
The tricky part is that i want the ...
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Audio Mixer Circuit with Individual Volume
I'm trying to make an audio mixer circuit based on the amplifier circuit published by Scott Campbell.
I have no knowledge of opamps so I'm taking it mostly as-is but the input signal I am going to ...
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What's the relationship among speaker amp IC's supply voltage and gain?
I am new to designing audio circuit. Looking at TI TAS6424 class-D amplifier (https://www.ti.com/lit/gpn/tas6424-q1), on section 9.3.3 p.23, it mentioned volume control from -100 to +24 dB.
Given the ...
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Guitar Pedal Signal Delay and Background Noise
I am designing a guitar pedal for overdrive/distortion from scratch and the circuit creates a lot of noise. The circuit also doesn't immediately start working, there is a delay before the signal makes ...
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Signal Processing Question--old school [closed]
I have a signal generator that creates a mostly 8kHz sine wave signal, with a couple quirks. It repeats in a 96ms pattern. Output is 220mV into a 1-20 ohm wire. It is used to provide wire guidance ...
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Why does this op-amp circuit require a resistor to ground?
The text in section 4.1 of Designing With Opamps - Part 1 reads:
Rin is the input resistor, and is needed because an opamp needs a
reference voltage at the input.
I don't see a similar resistor-to-...
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TMS3615NS Datasheet
I've got a tMS3615NS which should be an octave multiple tone synthesizer (dip28), I've found only a datasheet online, but the pinout is missing.
Has anyone a copy about this component or knows a ...
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Lots of audio codecs and few components: separate AGND from DGND?
I am trying to design a PCB that embeds 16 ADAU1787 audio codecs (ADC/DAC).
I want to design a board that connects to an FPGA through an FMC port and connects all the codecs to output connectors (...
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SDRAM and I2S on STM32
I am using an STM32F429 discovery board to develop a DSP platform for making some sound effects. I have I2S streaming and passing through, and I have SDRAM configured where I can talk to it and even ...
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Can an ESP32 be fed an audio signal and then output that audio to a Bluetooth speaker?
I have a CODEC circuit with a AUX audio output. Is it possible to connect that output back to the ESP32 and transmit to a Bluetooth speaker using the ESP32-A2DP library?
If so, would this be the ...
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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 long is the S/PDIF preamble?
I have a simple S/PDIF protocol question that I can't find the answer to anywhere. I'm trying to understand the protocol, and everywhere I look says the same thing: The length of a preamble pattern is ...
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Audio amp board keep blowing fuses
I have a electronic piano that stopped working. After opening I case I found that one fuse on the amplifier PCB had blown. I replaced the fuses but they immediately blew again. I have investigated the ...
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Analysis of an RCL Filter Utilizing a Potentiometer as R
I am trying to calculate the parameters ζ, Q, Fo, Gain (dB), and BW of this circuit. I am confident in the following equations:
Fo = 1 / (2 * π * √(L2 * C1)) ; Q = 1 / (2 * ζ) ; BW = Fo / Q
R2 = R5; ...
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Intentionally cutting off an audio signal at high volume
TL;DR: I am looking for a the best way to amplify all external sound but cut off at a hearing safe level.
I am attempting to incorporate active ear protection into an old SPH-4 helicopter helmet. I ...
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Would this Op-Amp instrument mixer design work properly?
After searching for a while about op amp audio mixers, I wanted to design one myself and designed the circuit below. I wanted to have 4 inputs and control the gain and volume for each. I think my ...
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Audio mixer, one output to multiple inputs
I'm trying to create a device that will take one stereo input and send it to 4 or more audio Bluetooth transmitters. This way, I can connect my prjoector to it and everyone watching can listen in on ...
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Audio noise/feedback through speakers from HDMI (DIY projector)
I have built a projector and it's mostly working except I'm having issues with speaker noise, I'm not an expert with this sort of thing at all so I'll try my best to explain.
I have 12 V DC coming ...
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Audio Mixer Circuit - DIY
I want to build a simple audio mixer circuit with help of TL072 IC's.
The following is what I want:
Mix two/three(optional) stereo signals into one, and then live out into 3 outputs (1 for amplifier, ...
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What is this following filter circuit called? (For amplifiers)
Noob here. I have a doubt on these passive low and high pass filters for amplifiers. If this is called high pass filter (which is doubled in series),
then what is this filter circuit called?
Here's ...
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Recreation of SparkFun's Musical Instrument shield with ESP32 not outputting any audio - how to troubleshoot or any obvious mistakes?
I recreated a shield. I tested all the voltages (5, 3.3 and 1.8) and they are where they should be. There are two crystals on my PCB to change to the smaller one eventually. I only put one crystal on (...
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Is there a momentary switch that cuts the signal only the very instant it is pressed?
I am trying to build a guitar kill switch that would behave like a typical momentary switch, but with a twist: I would like the audio signal to be interrupted only the very moment I press the button (...
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How to properly connect oscillator circuit to amplifier?
edit v2:
Schematics:
The ic on the left is a 40106, and the thing inside is a Schmitt trigger with inverting output.
In 'edit v1' below you can see a wiring diagram.
edit v1:
Rough schematics and ...
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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 ...
