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

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0
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0answers
23 views

How do I change the output volume of this audio amplifier circuit?

In the circuit below, where would I place an audio taper potentiometer to modulate the output volume level? Which of the resistors should get replaced with the pot and why? If understand ...
0
votes
1answer
20 views

How to design a single-ended to differential converter with audio transformer?

I am attempting to build an audio amplifier that accepts an arbitrary stereo input signal via a 3.5mm connector. My objective is to convert that single-ended input into a balanced AND differential ...
4
votes
4answers
160 views

Transfer Function for a combination of filters

simulate this circuit – Schematic created using CircuitLab I am currently working on trying to determine the transfer function for the audio tone circuit pictured. $$R_1 = t \times ...
-2
votes
0answers
32 views

Driving stereo speakers using AUX [on hold]

I have an old pair of Sony's SS-GNZ5D speakers which I had got with my stereo system. Now I don't use my stereo system anymore. So, I am planning to use the two speakers directly from the 3.5mm AUX, ...
-2
votes
3answers
85 views

Op Amps and High Pass Filters; Low Audio Volume [on hold]

I'm working on an audio crossover for a friend's stereo system. I have a passive design that uses a single 330uF in series with the positive audio line. It works like a charm , but I'd like to see if ...
-8
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0answers
94 views

Analogic Audio via Arduino [on hold]

I need to make a project with Arduino. I would know how take an analogic signal from a Arduino's shield (if exist) and send via wireless. Sorry for question I am new. Thanks for answers.
0
votes
1answer
17 views

VS1053 with SMD speaker, amplifier necessary?

I am working on device that looks a bit like a tablet. It consists of a display and a software controlled by touch on it. It uses the SAMA5D3 MCU from Atmel running linux. I decided to implement ...
2
votes
1answer
99 views

Can you identify this Bose car amp burned part? [closed]

Many more pictures here The radio and amp stopped working after a battery jumpstart. I fixed the radio by simply changing a fuse but the amp has a burned part. I tried contacting Bose to no avail. ...
1
vote
1answer
28 views

Audio High Pass Crossover Question

I'm doing a sound system for\with a friend of mine (I've done many, many before).... In the past I've done either simple L\C or LC crossovers, but I've been looking around for something I can build ...
1
vote
1answer
37 views

4 pole to 3.5mm female

I have a circuit board I took from a broken wireless headset, and I plan of reusing it by soldering a 3.5mm plug to where the speakers was connected. So I could plugin whatever headset I want. But ...
0
votes
0answers
10 views

How to stream audio over bluetooth to a device, use a bluetooth modeule with AVR atmega32?

I am trying to finish off a project I am working on that consists of an AVR atmega32 MCU and an on-board op-amp for audio amplification. Currently the device uses a hard wired connection for an audio ...
0
votes
1answer
39 views

Sending power to passive subwoofer via RCA connections

I have a home theater receiver with a powered subwoofer output and a matching passive subwoofer. I've always connected these two items using speaker wire. Recently I moved into a place that has ...
1
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3answers
54 views

Convert MP3 recording of data casette to serial data

I have a retro EMCO F1P CNC machine with a matching M1 controller that comes with mini data cassettes containing the "Machine State Data" which must be fed into registers of the controller before ...
1
vote
2answers
74 views

What is the purpose of a turntable's ground wire?

Many turntables, such as the ever popular Technics SL-1200 mk2 have a separate ground wire which attaches to the chassis of the mixer or preamp you have your turntable connected to. It's also a ...
-1
votes
0answers
21 views

Hardware device bluetooth transmitter to iOS

I'm currently creating an app using bluetooth to record music, especially my voice. I'm thinking of creating hardware attached with microphone, so that inside hardware can reduce the noise sound and ...
14
votes
2answers
1k views

White hairs inside a headphones cable

I have a cheap set of Phillips SHE3000 earphones with a broken wire on the plug. Since I was repairing another set of headphones, with the same problem, I bought an extra plug, just to try repairing ...
0
votes
1answer
122 views

Class AB amplifier Design help

I need help designing a class ab amplifier to power an 8 ohm 0.2W speaker to create an alarm sound. I'm outputting a sine wave at 150Hz and 5Vpp from a TI microprocessor. Questions 1: A class AB ...
0
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0answers
39 views

Audio recorder takes more time than expected

I'm building an Audio recorder with PIC32, that store the recorded audio in a SD card. I have a problem that happeans with both the compiler mikroC (using swap file) and MPLAB X IDE (using fatfs ...
0
votes
1answer
44 views

How to wire this component (-4dB audio)

Getting frustrated because I don't understand what this -4dB thing is in the circuit and I can't figure out how to wire it correctly or even if I have the right part. I have a 3.5mm mono audio jack ...
2
votes
1answer
97 views

Playing WAV audio files from an SD card on Wiring board?

I'm using the Wiring framework for building a custom alarm clock. So far, I've been able to work with several Arduino libraries on Wiring, just by including Wiring.h instead of Arduino.h, as ...
0
votes
0answers
9 views

Arduino Board with Microphone [migrated]

I have this microphone (http://www.digikey.com/product-detail/en/CMA-4544PF-W/102-1721-ND/1869981) and an Arduino Uno board. I'm trying to read audio values off of my microphone (to test the noise of ...
-2
votes
2answers
61 views

Suggestions for a simple microcontroller [closed]

Please suggest a simple digital solution for an equalizer implementation. I am not looking for any feature heavy DSP based IC, since my application only requires some minor adjustments on the bass and ...
1
vote
1answer
56 views

DC offset spike?

A week or so ago, I accidentally damaged one of the speakers of my audio system, most probably because of a loud and high-pitched distortion (noise? - it's basically a "pop" when ...
1
vote
1answer
49 views

is it possible to ignore the audio jack? [closed]

i would like to have a headphone jack with an on/off button, so that the jack will still be connected to the device (computer, phone etc') but the device would ignore it. does such a thing exist? and ...
1
vote
1answer
29 views

ASP solution for sound enhancement [closed]

I built a stereo speaker and to an extent it sounds good. But I noticed, by changing the EQ to "Rock" genre in my MP3 player, the instrument clarity became more clear and vocals were more fuller, ...
2
votes
1answer
34 views

Reading Flow Meters from Mic Port

I am attempting to read two hall-effect flow meters through the audio-in (mic) port of an Android device. I want to be able to read both flow meters independently. The audio-in port is a standard ...
0
votes
0answers
36 views

How to output audio using an altera DE0 FPGA?

I am working on a project that involves realtime image processing using altera DE0 fpga board. Due to the nature of the project I am also really interested in including audio output. However according ...
0
votes
1answer
52 views

In what order should I isolate and attenuate an audio signal?

I have a cheap bluetooth audio module (with no documentation) that outputs a signal greater than line-level. It was probably designed to be connected directly to small speakers, since the ground on ...
0
votes
1answer
110 views

Ghosts? Speakers playing sound from Raspberry Pi 2 without being connected [closed]

Yesterday I discovered something really strange: my speakers were influenced by my Raspberry Pi without having the headphone jack plugged in. Well okay, that does not sound very special, since they're ...
1
vote
1answer
32 views

Getting started on Voice recording and play back [closed]

I am looking for those small ICs as in Toys and in water level indicators , that plays a recorded voice. I cut open a toy car that plays a a few lines of song, but I found it COB. So can someone ...
3
votes
1answer
90 views

LM386 and low-pass filter

First time here, so here I am with an electronic-related question. Please note that altough I have a scientific background, I'm quite new to electronics. Setup I'm trying to build a small audio amp ...
0
votes
1answer
35 views

i have a question about a amplifier im working on

the amp is a radioshack mpa250. I hooked it up, and took the top cover off to see how big the transformer and caps were. theres two 80v, 10000uf caps in there, with a 40.5v transformer... i checked ...
0
votes
1answer
29 views

How to create a bluetooth module that is both a master and slave?

I'm working on a project that involves having a bluetooth module be a master and slave. I am a dummy when it comes to these things. Basically i need one device like an iPhone to be able to ...
0
votes
1answer
32 views

Data transfer to Android USB Digital Audio device

Android 5.0 (API level 21) and above supports a subset of USB audio class 1 (UAC1) features: https://source.android.com/devices/audio/usb.html related links: ...
0
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2answers
58 views

Real time digital audio frequency changing device

I want to make a device, which takes an AC audio signal like a guitar pickup signal, or piano or what have you as input, and changes the pitch using this function: ...
0
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0answers
41 views

Connecting an tube output transformer “wrong” to get different primary impedance

I'd like to build a tube amplifier (not for guitar), but have a problem in that it seems I cannot get an output transformer that is proper for the tube (required primary impedance and power rating), ...
3
votes
2answers
185 views

Creating a loud cracking sound to scare cats away forever and ever

So we have some hardcore cats in our area, recording their glorious conquests with excrement. They don't scare easily. I'll be conducting psychological warfare, they must start associating some form ...
3
votes
2answers
71 views

How can I protect a DC switch from arcing and sparks?

I have a DC switch that is being used as the main power switch for an audio amplifier project I am working on. The schematic is shown below. (a few things are wrong with that circuit, but have since ...
1
vote
1answer
55 views

What connector is appropriate for a 500V electrostatic speaker?

A research group just bought an electrostatic speaker that came with a long cable that is meant to be soldered to the speaker wires. However it would be more convenient to have a connector(s) there. ...
0
votes
0answers
92 views

Connecting RGB LED light strip to LP3950 color LED driver

I want create color organ controller for use with 12V-24V RGB LED light strip. The LED light color changes need be synchronized to audio signal with both amplitude (beat) and frequency methods (4 ...
1
vote
2answers
93 views

What is difference between Power-GND vs Pre-GND?

I would like to know the difference between different types of Grounds like Power-GND vs Pre-GND. Are all the grounds not same? Cant we connect the device to any one of these grounds? In my ...
1
vote
1answer
53 views

What is “Power Supply Pumping”?

I recently came across the term "Power Supply Pumping" in an answer provided to me in return to one of my questions. Although I tried googling I didn't have good luck with it. I would appreciate if ...
0
votes
2answers
55 views

Multiple audio inputs driven by one MP3 player output

I wish to make the following design using TPA3122D2N as a DIY project. Is it possible I make two or three of these units and share the MP3 players output among all three inputs on the TPA3122 IC? ...
0
votes
2answers
116 views

Need help with a VU meter analog signal

I am making an Arduino VU meter. I need to convert an analog AC audio signal to a varying positive DC signal. I would like the following outputs: 2.5 V output at 0 V input (from VM1); 5 V at maximum ...
0
votes
1answer
32 views

Filter Analysis using Audio Analyzer

I have a RC low pass and ferrite bead cap filter combination on my circuit board. I am trying to use Audio Analyzer U8903 to analyze the gain response of the filter. I see quite different result in ...
0
votes
1answer
77 views

Question about MCU's, and Audio Manipulation

Ok, so I've been doing some research trying to find something like an audio MCU\DSP with a built in audio filter; for instance, something that I could manipulate audio with to get a final filtered ...
5
votes
1answer
161 views

Custom WAVE file results in different sound profile than created

My problem is as following: I'm trying to use my sound card to produce a custom repeating wave pattern which I will use in some laboratory test setup. My curve is based on a combination of a couple ...
0
votes
0answers
29 views

Phone audio jack IR transmitter and receiver

Note: I'm quite new to electronics so I apologize for any dumb questions. Hi, I'm trying to make an infrared transciever module for my smartphone using it's audio jack. I'd like to be able to record ...
0
votes
2answers
78 views

Change AC signal frequency without changing the voltage

I have a non constant -/+1 Volts to -/+7 Volts AC audio signal. I want to design a device that takes this input signal, doubles the frequency, without changing the voltage. So, the output voltage is ...
1
vote
1answer
39 views

Does using multiple speakers degrade quality?

I have an amp and 4 speakers. I want to "daisy chain" the speakers together like so: I'm trying to figure out if doing series and/or parallel connections in the diagram above will degrade the sound ...