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Musical & Effects Circuits
Musical & Effects Circuits
There are many ways to create a stereo effect. If you were miking a piano, a string section, or some other large sound source, you`d probably stick up a pair of directional mikes and assign them left and right. But what if you want to "enlarge" a lead vocalist? Or, how about other inherently mono instruments like an electric guitar or a...
Sound Effects Generator
This circuit uses a UM3561 IC to produce four different sound effects. Nothing too complicated here. The IC produces all the sound effects, the output at Pin 3 being amplified by the transistor. A 64 ohm loudspeaker can be substituted in place of the 56 ohm resistor and 8 ohm loudspeaker. The 2 pole 4 way switch controls the sound effects.
Sound Effects Generator 2
This circuit uses the Holtek HT2884 IC to produce 8 different sound effects. All sound effects are generated internally by the HT2884 IC. Power is a 3 Volt battery, but the IC will work with any voltage between 2.5 and 5 Volts. Switch S1 is the on / off switch. The output at pin 10 is amplified and drives a small 8 ohm loudspeaker. Pressing S3...
Tone Generator with 555
this tone generator can be used to control your robot. you will need to use the tone decoder for this. to widen the range, higher or lower - substitute a higher, or lower valued capacitor for c1. for frequencies about 5khz and 15khz, use a piezoelectric element as the speaker. Use a miniature speaker for frequencies under 5khz, and use an...
Precision Frequency generator 1 to 999 Hz Precision Metronome 1 to 999 beats per minute. CMos IC1 and IC2B quad AND gate form a 2.4576 MHz crystal oscillator plus a 2400 times divider. IC3A provides further division by 16, delivering a 64 Hz stable frequency square wave. This frequency is multiplied (by means of Phase Locked Loop IC5, double...
Panner Waveform Generator
This device is a microprocessor controlled waveform generator that can be used for driving a voltage controlled stereo panner for music applications. Panning is simply the movement of a mono audio signal between the left and right channels of a stereo sound system. The circuit can also be used to drive other voltage controlled modules that...
Guitar Reverb Effect
This circuit features clipping indicators on the preamp and reverb recovery stages, allowing for the optimal gain settings. The guitar input stage is a class A amplifier with adjustable bias. A 2N3906 PNP tranistor is used for a low noise design on this stage. The output of the preamp stage is sent to three places: the output mixer amp, the...
CW Sidetone Generator
This circuit is about as good as it gets for generating morse code tones. It may be used as a code practice oscillator, a tone generator for a keyer, a sidetone oscillator for a CW transmitter or an audio Modulated CW (MCW) generator for an FM transmitter or repeater.
Guitar Reverb II
This is my second-generation guitar reverb circuit. The fidelity is much improved over the earlier design, it is suitable for use as a front-end to a guitar amplifier. This circuit features clipping indicators on the preamp and reverb recovery stages, allowing for the optimal gain settings.
8 Note Tune Player
This neat little circuit can play 8 note tunes at any speed you want. You select the notes with 8 trim pots. The speed in selected through a ninth pot. The circuit draws very little power and can be powered by a 9 volt battery, with the addition of a 7805 regulator to power the TTL logic used.
audio white noise generator
This is a circuit that generates white noise, rolled-off to drive earphones or a small speaker. White noise creates is a "rushing" sound, which sounds something like air rushing by your ear(s). White noise would be flat with frequency, and since this circuit rolls off within the audio range, I refer to it as "rolled-off" noise. White (or...
Electrostatic Loudspeakers project
Building ESLs involves the use of tools and materials that if handled improperly can be hazardous. Please make sure you know how to use these things before you begin. By all means, use safety glasses at all times. If would be foolish to trade your vision for the pursuit of audio ecstasy!
Audio frequency generator
My generator can produce sine- and squarewaves with frequencies between 1 Hz and 100 kHz and amplitudes ranging from zero to 1.55 Veff in 600 Ohms. Sinewave distortion is 0.1% or less between 20 Hz and 20 kHz, somewhat greater outside this region. The output voltage varies less than 0.1 dB within the audio range (20 Hz to 20 kHz); there is some...
Sola Sound ToneBender
This is probably one of the most legendary fuzz pedals that has ever existed, and for good reason too! This thing can produce some completely saturated fuzz that is capable of slipping into feedback easily if you crank it up loud enough. I just can't say enough about this pedal. This is, without a doubt, my all-time favorite fuzzer. It's a...
Simple Toy Organ using 555
This is a simple oscillator with multiple resistors in serie. When you press any switch, the circuit starts oscillating. You can user variable resistors instead the 1k resistors. Using variable resistors you will be able to tune the frecuency for each note. You cannot be able to press two keys at the same time because the frecuency will change....
Guitar Overdrive circuits
Although labelled as distortion, this is a soft clipping device, using germanium diodes. It's a good example of how little you need for a good basic sound. You could easily swap (or switch) these diodes to silicon types for hard clipping. Not necessarily the next pedal chronologically, but look at how similar this design is. It uses 2 silicon...
Wah pedal for Guitar
The right way to do this is with a small extra pc board to accommodate the new components, firmly secured inside the case, and wired carefully and neatly. Unfortunately, I did none of these things, but it worked reliably and if it ain't broke. I used a pot for the resonance control mounted just forward of the socket on the side of the case, and...
Surround Sound Decoder
The particular circuit does?t have the requirement to replace the trade decoders Surround, because this they have many more facilities and possibilities. It give however the possibility in many try with this article of decoding. The coding in Stereo Dolby Surround show the tendency to be abandoned and is replaced with digital DTS, Dolby 5.1...
Programmable Sound Generator
The AY-3-8910/8912 is a register oriented Programmable Sound Generator (PSG). Communication between the processor and the PSG is based on the concept of memory-mapped I/O. Control commands are issued to the PSG by writing to 16 memory-mapped registers. Each of the 16 registers within the PSG is also readable so that the microprocessor can...
This is simple almost beyond belief for distortion devices. Two transistors, four resistors, three capacitors, and two controls make all that tone. The first transistor is set up with the simplest of arrangements - input through a DC blocking capacitor directly to the base, emitter grounded, and a single collector resistor; the driven load is a...
Univibe - Trem Face and Others
Where it really shines is in the univibe. The 'vibe uses a dual section, reverse log taper pot that's just a bit easier to find than a dinosaur's tooth. If we notice that the pot is really wired as two variable resistors, we can use an LED/dual LDR module like the VT5C3/2, which costs about $5 from Newark and other electronics distributors. To...
Midi Generator with ATtiny26-8PI
This circuit based on ATtiny26 but it could be anyone microcontroller of AVR family. Produce stable one MIDI tone and you can change it by press some keys like to change midi channel 0-15 , velocity 0-127, pitch 0-127. It is start from center tone (C) at channel 0 with velocity 30. Every tone is equivalence with two midi events "note on" and...
Music Instrument design
For those who don't know what a Theremin is, it's one of the first synths ever made and it's named after his inventor, Mr. Leon Theremin (a Russian guy). It's perhaps the only instrument which you don't actually touch: there's an antenna, and as the musician moves his hand near it, the pitch changes. That's the thing Page used in "Whole Lotta...
Big Ben Sound circuit
This circuit produces the famous Big Ben sound. It produces the "ding dong" sound when switched ON. Basically the circuit alternates between two frequencies which are adjustable. This produces the "ding-dong" sound. The first IC(left) oscillates at about 1Hz. The second IC's tone is modulated by the changing voltage at the output of the first...
Melody generator schematic
This tiny circuit comprising of a single 3 terminal IC UM66 can be built small enough to be placed inside a greeting card and operated off a single 3V flat button cell. There is not much to the circuit. The UM66 is connected to its supply and its output fed to a transistor for amplification. You can either use a 4ohm speaker or a " flat"...
Two identical integrated circuits, U1 and U2, known as "hex inverters" are used for the theremin's primary functions. They are CMOS (Complimentary Symmetry Metal Oxide Semiconductor) devices, typically used in digital circuits to perform a logic function called "inversion." Each IC contains six identical sections; thus the term "hex inverter."...
EasyVibe guitar effect
I aimed to copy the sound rather than the vintage circuit. Easy to build, low current consumption, no signal level changes on bypass, quiet and, most importantly, it does that Bridge of Sighs thing.
Zombie Chorus Guitar effect
This is my reincarnation of the EH Small Clone and Roland CE-1. Unlike the Clone it has a proper depth control. It also has a switch to change between the CE-1 like 512 stage delay and the Clone's 1024 stage delay. Current consumption is very low and the circuit works down to below 6V to extend battery life. I managed to eliminate a number of...
Guitar Crash Sync effect
This is an oscillator sync circuit that gives the kind of effect you find on old analogue synths. Oscillator synchronisation is performed by using one oscillator to reset another. In this instance the guitar signal is used to reset an oscillator running at a higher sweepable frequency. The effect is not dissimilar to flanging. Not one for the...
Guitar OmniDrive effect
This is a versatile distortion pedal. Think of it as analogue modelling, using analogue circuitry to model a wide range of analogue distortion devices. It includes the main elements found in the majority of distortion boxes. The unit comprises four sections: A pre-amplifier with switchable treble boost. A switchable low pass filter. A switchable...
Guitar Titan Boost and Titan Octave effects
A simple boost circuit that gives 30 volts pk/pk output using a 9 volt battery. The addition of a Ge diode bridge makes a surprisingly good octave box.
Frobnicator effect for Guitar
This is a ring-modulator which doubles as a tremolo. It was designed as a replacement for the somewhat over-complicated ElectroHarmonix Frequency Analyzer with its ridiculous high-voltage wall-wort and huge metal box. I've got it down to a 3080 OTA and a dual op-amp.
Audio Filters Circuits
Audio Amplifier Circuits
Audio Oscillator Circuits
Audio Mixer Circuits
Audio Equalizer Circuits
Audio Tone Balance Circuits
Beeper Buzzer Circuits
Vacuum-Tube Valves Circuits
Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
DIY HV Variable Capacitor
DIY PMA Alternator Plans
Digital Signal Integrity