Questions tagged [guitar-pedal]
Electronics circuits design for guitar pedals
140
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Why NPN and PNP in parallel in this distortion pedal circuit?
I've come across a guitar pedal circuit called a "Tube Sound Overdrive". The schematic is shown below. It looks like a typical common emitter transistor circuit with an adjustable bias (RV1),...
- 500
8
votes
2
answers
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Please help me debug my circuit
I am trying to build a guitar pedal but am unfortunately failing. I have about a high school physics understanding of electronic circuits, but the readings I am getting seem impossible to me. I might ...
- 183
7
votes
1
answer
660
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Stompbox not working
Today I've soldered my clone of ZVEX Wooly Mammoth and when I started testing, it didn't give a sound. Hours of visual and multimeter inspections gave me no clue about a mistake. So, I appreciate any ...
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7
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2
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What does this circuit symbol mean? [duplicate]
I'm a student who is trying to build a wah pedal for a guitar. I came across this diagram for how to wire the circuit (from this site) :
Within the diagram, I am not sure what the following symbol ...
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6
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2
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Reasons for choosing a transistor instead of an op-amp as a buffer
I have often seen circuits for guitar pedals that use an emitter-follower configuration as the input and output buffer (see example below). If an op-amp can provide a greater input impedance / lower ...
- 464
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3
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Overdrive guitar pedal sounds better without a clipping diode
I built a guitar pedal which looks like this (the schematic is a clone of a Tube Screamer) and I have a question regarding something unusual I discovered.
There are two diodes, D1 and D2, which ...
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5
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2
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Single supply non-inverting amplifier using op amp
I'm working on building a distortion guitar effect pedal for an analog electronics class I'm taking. I am struggling with building an amplifying circuit using an op amp (we just began learning about ...
5
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1
answer
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Eliminating the humming noise from a cheap SMPS
I am trying to build a power supply unit that powers eight 9V guitar pedals (usually pedals consume 10-100mA). So, I thought I'd buy 8 cheap 9V-1A SMPS adapters and probably fix some bypass capacitors ...
5
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1
answer
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Need help designing and implementing an op-amp based distortion circuit
I've been attempting to design a distortion pedal for use with my bass guitar and amplifier. The simulations in LTspice were promising, I moved to implement it and, in short, it did not work.
Note: ...
4
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1
answer
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I am rewiring my old guitar and I need help with the potentiometers
Is it possible to convert a 250 kΩ potentiometer to 500 kΩ or a 500 kΩ stereo potentiometer to mono?
I am finding it difficult to locate a 500 kΩ mono potentiometer.
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Simple fuzz pedal using breadboard
Complete newbie here.
I've been trying to reproduce a simple fuzz pedal using breadboard. Here is the scheme:
And here is the current state of my breadboard:
The only sound I hear is white noise ...
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3
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2
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Why does this circuit use a transistor buffer even though there is an high input impedance op amp afterwards?
Regarding this circuit I found on www.geofex.com detailing the famous Tube Screamer guitar pedal
(source: geofex.com)
I don't understand the purpose of the BJT input emitter follower transistor. ...
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3
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2
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Opamp Design for Low Impedance Sources?
I am terribly confused ... I tried myself at building a low impedance guitar pickup some time ago.
Quick LowZ Pickup Intro
Basically just two loops of aluminium with two magnets, a humbucking guitar ...
- 151
3
votes
3
answers
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Capacitor into resistor to ground
I recently started learning electronics on my own due to interest in audio effects because I play guitar so:
I thought I'd start out with distortion pedals, they seemed the simplest to begin with.
...
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3
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2
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Does anyone know how the low tone control of the Boss Metalzone works?
https://electricdruid.net/boss-mt-2-metal-zone-pedal-analysis/
https://sound-au.com/articles/gyrator-filters.htm#s9
I have been using these websites to try and work out how the eq works, but I've ...
- 35
3
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1
answer
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Original cry baby wah wah analysis
I have been given to understand the original crybaby wah schematics. But I can barely understand anything regarding the circuit itself! Any kind of suggestion and help from anyone would be very ...
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2
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2
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Common-collector gain for guitar pedal
I am currently working on a distortion pedal. I have just made the initial input buffer to prevent loading the source signal. It is simply an NPN transistor in an emitter follower (common collector) ...
2
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2
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Purpose of 100 ohm resistor on guitar pedal output buffer
On the schematic for an Ibanez "Tube Screamer" there is a 100 ohm resistor in series with the output emitter follower:
The output impedance of this pedal is 1.2K:
It looks like RB has a ...
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2
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3
answers
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My (single ended, class A) tube amp sounds great while it's shutting off. What's happening?
So, I have guitar direct in to a single-ended class A (12AX7 and 6V6) Champ-style amp. The amp is from the 60s and unbranded, it's likely a Pepco (Pine Electronics) Silvertone style circuit. It's been ...
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2
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2
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E-Guitar / Bass amplifier Effects-Loop: Is there a standard for voltage levels & impedances? [duplicate]
Musical instrument amplifiers often have an "FX-loop" with a pair of jacks which can be used to interrupt the default connection between preamp & power amp, to put the preamplified ...
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2
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2
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Diode in feedback path of transistor (collector-base)?
This is the schematic for a fuzz circuit. Even knowing that the diode is probably what's providing the signal clipping, I still can't figure out how I'm supposed to analyze the circuit.
When V(...
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2
votes
1
answer
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Why does a Pull down resistor not affect AC
I've been reading up and trying to learn about Guitar Pedal circuits.
I have a very basic question about how a Pull Down resistor is used at the beginning and end of a circuit to avoid a popping ...
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2
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2
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Digital Audio Effects Design [closed]
I've recently graduated university with an MEng degree in Electrical and Electronic Engineering. As a third year project, I've used an ST-Microelectronics ARM Cortex-M4 based Nucleo microcontroller ...
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2
votes
2
answers
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viability of idea for low voltage signal clipping (distortion) for guitar effect
I want to create an guitar distortion effect.
What I want is a unity gain buffer op-amp that clips the signal.
In the drawing below there is a circuit found on this forum here
which will clip a very ...
- 289
2
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3
answers
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Is there any real world difference in upgrading TL071 to OPA314?
I have a DIY made guitar amp in which there is a TL071 preamp section. I read various opinions about how upgrading op amp improves that sound and how it doesn't do anything really... I'm quite ...
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2
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2
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562
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Gibson-style dual humbucker wiring with blend pot and integrated discrete MOSFET buffer using AAA batteries
I have been tinkering with creating a MOSFET buffer circuit for my guitar to boost the high impedance output from the pickups to help drive the signal through long cables and pedal boards. This also ...
2
votes
1
answer
488
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Audio Transformer output straight into an opamp?
Below is a circuit I'm working on.
It's a guitar input buffer featuring transformer isolation.
The transformer I'm using is pretty expensive and should be fairly linear, but I decided to add a graphic ...
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2
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2
answers
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Guitar signal input to Arduino UNO ADC - alternative part for TL972 op-amp
I'm trying to make a guitar pedal with atmega328 in Arduino but I've had trouble with input stage.
I found this circuit from electrosmash.com, but I can't find the TL972.
Are there any replacement for ...
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2
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1
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Help Needed with Voltage Controlled Synth Circuit
I am building a somewhat out-of-the-ordinary guitar pedal that involves some synth elements, namely controlled voltage. I'm a little confused by something that I suspect is actually pretty basic.
I ...
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2
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2
answers
510
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Pedal circuit not working on 9 V battery or 9 V AC adapter
I built a simple NPN fuzz pedal (negative ground) and soldered it up on some perf board. It works just as expected using my power supply but when hooking up to a 9 V battery or a 9 V DC adapter the ...
- 21
2
votes
1
answer
405
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Analog Switch times for popless audio
If I am using a CMOS switch, how much do I have to slow down the switch time so that I don't experience a pop in my audio signal out of my amplifier and how would I accomplish that?
The switch time ...
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2
votes
1
answer
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Can I use network cable for low voltage DC power?
I'm a guitar player with a crazy idea for a 2 part bypass looper:
Enclosure A is just big enough to house 4 footswitches and an ethernet jack.
Enclosure B has 9V DPDT relays to route audio ins and ...
- 21
2
votes
1
answer
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Function of resistor in OpAmp circuit
I came across this circuit as part of a larger circuit in a guitar effect pedal:
simulate this circuit – Schematic created using CircuitLab
I was wondering about the function of the resistor \$...
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2
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1
answer
484
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Routing Audio Ground - needed or not?
I'm trying to build a guitar pedal switcher (efectively a box that provides multiple effect loops that can be independently bypassed from a single microprocessor) and while building a working ...
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2
votes
0
answers
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Circuit simulation of a tremolo pedal not working
im a electrical engineering student here in Brazil and i have to build a tremolo effect for a electric guitar, but i'm not having luck in the simulation of my circuit and i dont know if im simulating ...
2
votes
0
answers
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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.
...
- 21
2
votes
0
answers
505
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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 ...
- 21
2
votes
0
answers
130
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Can arcing in IEC 60320 C13/C14 connectors damage a device?
I have a 'guitar effects power supply' built to supply 9v/12v/18v power to 🎸 guitar effects pedals. It is powered using a IEC 60320 C13/C14 power receptacle and cable.
After using this device for the ...
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3
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How to get +6V and -6V out of 12V PSU [duplicate]
I am designing a guitar pedal using OpAmps, and i need to feed them with +6V and -6V (beucase the musical signal is senoidal centered in 0V). I need to use a 12V DC PSU for the pedal, and i need to ...
1
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3
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Guitar pedal input stage buffer
In the below schematic for the Tube Screamer guitar pedal input buffer, there is a 1k resistor (R1) after the coupling capacitor (C1). What is the purpose of this resistor? It has no effect on the DC ...
- 464
1
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3
answers
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How to determine what capacitance is required for eliminating humming noise?
I've got power supply (transformer based) 9V powering modelling guitar effect processor. That noise gets amplified and it hurts.
Humming noise is 100Hz rectified mains. Processor takes 300mA 9V (...
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2
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MXR Distortion + guitar pedal schematic - meaning of +4.5V
I found this schematic of the "MXR Distortion +" guitar pedal.
I am trying to rebuild it, but I have some doubts about this +4.5V in the bottom left corner.
What does it mean?
I mean, I have only 1 ...
- 155
1
vote
3
answers
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Audio Signal Switching - "DPDT switch vs. 4066"
I've got a signal coming from an electric guitar and I need to switch it. Basically it's a distortion circuit. I need to switch between the distortion and clean (directly connected to the output)
My ...
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1
vote
3
answers
113
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Bias voltage in non-inverting op-amp topology being pulled down
I decided to quickly put together a circuit today but found an issue that has sometimes happened when making circuits with TL072.
Briefly, the circuit is a non-inverting amp with about 34dB gain in ...
1
vote
1
answer
137
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What's going on in these op amp feedback paths?
Here is the schematic to my new Behringer UM300 guitar distortion pedal.
Most of the circuitry is pretty straightforward (a lot for the $22 I paid!) but can someone explain what the emitter follower ...
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1
vote
1
answer
2k
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Guitar signal with opamp boost
Hi just having some issues understanding what's happening with my opamp circuit.
Vin is a Sine wave at 1kHz and VG is 4.5V.
From what I understand this circuit should boost the signal I provide it ...
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1
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1
answer
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Switching capacitors in a guitar effects pedal
I've built a linear power booster - schematic here:
http://pedalparts.co.uk/docs/LPB-V3.pdf
I did it on veroboard:
You'll note that it gives you the option of having different capacitor values to ...
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1
answer
1k
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What is wrong with my guitar amp?
I found this 1W guitar amp design on the Internet:
http://www.diale.org/punch.html
And I am trying to build it on the protoboard. I could not find the IC TDA7052, instead I've got the a TDA7052B. ...
- 257
1
vote
2
answers
96
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Guitar distortion pedal gain
I am working on a custom distortion pedal. Here is the circuit:
As we can see, we have the following flow:
Input buffer -> gain stage with hard clipping -> buffer -> tone control using ...
1
vote
2
answers
525
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TL072 based circuit generates loud noise
This circuit, designed as a bass scream, keeps generating a low noise about the same loudness as the guitar signal on the output.
