Questions tagged [audio]

Questions about designing electronics for measuring, processing, and amplifying audio signals.

274 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
6
votes
0answers
614 views

LM386 guitar practice amp circuit not working, need help finding mistake

I'm very new to electronics and I built this guitar amp circuit on a breadboard: and it was working really nicely. Now I've decided to put the circuit on a universal PCB which I'll use in the actual ...
3
votes
2answers
234 views

Enhancing the bass response of an audio isolation transformer

Below is a simple buffer circuit using an isolation transformer : The green trace is the output of the transformer and the blue trace is the input signal (20hz to 20Khz sine wave). As you can see the ...
3
votes
1answer
229 views

Amplify Raspberry Pi Zero W Audio with 60s Tube amplifier circuit

First of all, thank you for taking a look at my question. Electronics is not my field of expertise, and I have found myself a bit stuck. I have been restoring some old 50s and 60s tube amplified ...
3
votes
1answer
239 views

Ultra low power audio recorder

I'm trying to design an ultra low power audio recorder, in order to monitor ground noise in rural areas. The circuit I'm working on is based on a microcontroller (STM32L100RC) and an audio codec (...
3
votes
1answer
482 views

How would a transistor's hFE affect a phase shift oscillator?

I have a phase shift oscillator circuit from a drum machine that I would like to reproduce as faithfully to the original as possible. My problem is that the 40 year old design uses a transistor (...
2
votes
0answers
114 views

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 ...
2
votes
0answers
57 views

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 ...
2
votes
0answers
82 views

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 ...
2
votes
0answers
80 views

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 ...
2
votes
0answers
101 views

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 ...
2
votes
0answers
184 views

Can I replace electret microphone with audio connector and expect similar results (sound levels)?

Last night I built a circuit that allows me to obtain sound via a SEED Grove Sound Sensor and input it into my MKR Zero for frequency analysis. It's as simple as this: simulate this circuit – ...
2
votes
1answer
359 views

Dolby HX PRO implementation on existing tape recording deck

I'm experimenting the implementation of Dolby HX PRO's IC into an old stereo Fostex tape deck to improve high frequency and headroom capabilities. HX PRO works as a dynamic processor with the BIAS ...
2
votes
1answer
161 views

Can I connect a MEMS mic directly to this spectrum analizer 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 ...
2
votes
0answers
61 views

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 ...
2
votes
1answer
174 views

fixing the amplifier in an old arcade machine

I just joined and need help. I'm trying to fix the amplifier in my Chicago coin speedway arcade machine. It basically works but it has a bad hum in it. I did replace a couple capacitors that were ...
2
votes
0answers
269 views

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, ...
2
votes
0answers
226 views

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 ...
2
votes
0answers
1k views

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 ...
2
votes
0answers
513 views

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 ...
2
votes
0answers
1k views

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 ...
2
votes
0answers
81 views

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 ...
2
votes
0answers
252 views

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 ...
2
votes
0answers
274 views

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,...
2
votes
0answers
2k views

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 ...
2
votes
1answer
136 views

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 ...
1
vote
0answers
21 views

Diagnosing USB Power bank shut-off on load application

I'm trying to create a small bluetooth boombox-style speaker, but am having trouble powering the device from a USB battery bank. Fundamental Problem: The power bank "shuts off" as soon as the load is ...
1
vote
0answers
42 views

Hi-Z input mixing circuit for Guitar

I am creating a guitar pedal. I want to mix together 3 sources: Coming from electric guitar (or through another guitar pedal) Coming from filtered PWM (for the purpose of generating sinusoidal signal)...
1
vote
0answers
38 views

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 ...
1
vote
0answers
51 views

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 ...
1
vote
0answers
28 views

Difference in output between digital codec and analog filter

I'm working on a project which deals with filtering audio signals with a Low Pass Filter and amplifying the output. Currently, we are solving this using the TLV320AIC3111 audio codec by Texas ...
1
vote
0answers
46 views

Should I connect metal enclosure to -V or to virtual ground?

I've built a headphone amplifier powered by a switch-mode 2-pin wall wart power supply. Internally a virtual ground is created by dividing and buffering the supply voltage. Input and output signals ...
1
vote
0answers
76 views

Struggling to get an amplified sine wave over a small inductor at low frequencies

I am building a power amplifier circuit to amplify a sine wave over an inductor from a function generator. However because the inductor is small and i'm running at a low frequency I am getting ...
1
vote
0answers
65 views

2 Crossovers in parallel: how are frequencies distributed?

So, the other day I connected on parallel a dual-voice subwoofer-system (a Pyle XSUB1-150-4-12d crossover — like this one ... link might be unavailable after Aug 28, 2019 ... — and 2 individual ...
1
vote
0answers
51 views

DIY high fidelity audio using delta sigma adc

This question may be too general, but I will include all the details that I can. My end goal is to achieve a super high-resolution spectrogram of any recording I choose to make. By doing some tests I ...
1
vote
0answers
49 views

Guitar to iPhone JFET pre-amp circuit issue

I am following this tutorial to build a simple JFET pre-amp to connect a guitar to an iphone. This is the schematic: I have soldered the components as per the schematic directly onto the 1/4" mono ...
1
vote
0answers
44 views

Voltage step up module and if I am using it correctly

I am making a "simple" bluetooth speaker and have followed instructions from a Youtube video on how to assemble the components I have bought. However... I am finding that the rechargeable li-po ...
1
vote
1answer
61 views

Low pass to high pass filter conversion

Ripples from Mutable Instruments (open hardware) is a low pass 4th order filter. The schematic is found here https://mutable-instruments.net/modules/ripples/downloads/ripples_v40.pdf Can I swap ...
1
vote
0answers
42 views

Audio Amplifier Power Usage

I'm looking to add an audio amplifier to a circuit, in this case the TPA0211 in 5V mode for a full 2W of output. My rather dumb question is this: I should expect at least 400mA of current draw from ...
1
vote
0answers
188 views

How to Low-Pass PDM Output Data

I have a PDM-Mems Microphone which provides me with 101010 data, the Microphone has a Clock of 3Mhz. I read the manual about how PDM is generated, but I haven't worked with digital filters yet and in ...
1
vote
0answers
186 views

Low latency wireless audio transmitter

I am working on a project that requires low latency wireless point to point audio transmission at short distance using a digital transmission technique (ideally 24bit 96khz audio, 30 metre max) at a ...
1
vote
0answers
56 views

Why is my signal stronger in the positive than in the negative when i use 2n3819?

simulate this circuit – Schematic created using CircuitLab In the above circuit I have created a JFET amplifier for small signal purposes. When I run tests on the circuit, i get this weird ...
1
vote
1answer
136 views

Repair lifted ground pad on power amp

I'm repairing a 250W bass power amp board and one of the problems is that the pads for two ground wires have lifted off the board. It looks like it has had something of a bodge repair done before and ...
1
vote
0answers
255 views

How to make a piezo speaker louder with 5V?

I have connected a tiny piezo pc speaker (https://sktechworks.ca/wp-content/uploads/2017/11/Speaker.jpg) to an arduino and used to tone command to play a simple melody in repeat (square wave only ...
1
vote
1answer
50 views

Induction loop resistance calculation

I have been trying to build a simple induction loop amplifier. I am using TDA2040 as an output stage and it delivers 10 W (I limited it for that). I am using about 14 meters (1 mm thickness) loop. My ...
1
vote
2answers
161 views

Quick question. Will this mono/stereo switch system work on my mixer panel?

So basically, I designed a mixer panel for monitoring my band when we play live. However, some of us play with a stereo in ear monitoring system and some of us use a mono speaker by their feet. I don'...
1
vote
0answers
103 views

Differential bandpass filter Audio application

I am developing an Audio project which is required to output a signal between 10kHz - 40kHz at ±1V. The sound is produced from an AD9106 chip which is interfaced to the following circuit: When ...
1
vote
2answers
255 views

Unstability with tda 2002 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 ...
1
vote
1answer
173 views

THAT4315 audio analyzer - capacitors getting hot

I have designed a audio spectrum analyzer circuit with THAT4315 and a drivers for IN-13 bar graph nixie tube to visualize the signal level. To supply +-12V to the opamps, the Meanwell NSD15 module is ...
1
vote
0answers
187 views

audio output on my FPGA

I asked a very bad question related to this yesterday, sorry - this is more comprehensive and makes more sense. this is the manual for the nexys 4 FPGA i'm using https://reference.digilentinc.com/...
1
vote
0answers
140 views

Identifying Noise in 12AU7 Based Headphone Amplifier

I've been working on making a tube based headphone amplifier as a fun personal project. The amplifier is based around this 12AU7 vacuum tube. The project for the most part is following this existing ...