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FET based audio preamplifier
This is the circuit of a based audio preamplifier which has very low noise. One FET and one BJT are used in this circuit. The audio signal to be amplified is coupled to the base of FET Q1 using capacitor C1 and resistor R3. Base of transistor Q2 is coupled to the drain terminal of FET Q1. Transistor Q2 provides additional current gain. The final si
Guitar pre-amplifier using uA 741
A preamplifier circuit suitable for high impedance type electric guitar pickups is given here. The circuit is based on a uA 741 op-amp (IC1). The IC1 is wired as a non-inverting amplifier. The POT R1 can be used as a volume controller. The POT R6 can be used as tone controller. The switch S1 is used to produce brilliant or soft tonal...
LA3161 Stereo Preamplifier for car stereo 12V operation
LA3161 is an integrated 2 channel pre-amplifier intended for car stereo applications. LA3161 Stereo Preamplifier can be operated from 12V DC..
Magnetic pickup pre-amplifier circuit
A preamplifier for magnetic pickups of record players is shown here. The uA 741 is used as an AC coupled non-inverting amplifier operating on a single supply. The amplifier gain is decided by the feedback components in which C2 controls the low frequency roll-off characteristics while C4 reduces the gain at high frequency end to compensate for...
Stereo preamplifier with tone control
Here is the circuit diagram of an excellent stereo preamplifier with tone control using the IC TDA1524 from Phillips. The IC requires very few external components, has very low noise and has a wide power supply voltage range. POTs R1 to R4 can be used for controlling the volume, balance, bass and treble respectively. LED is D1 is a power ON indica
Telephone pickup preampliifer
Here is a simple circuit based on IC uA 741 that can be used to pickup voice from telephone lines without even contacting the line. If a high impedance magnetic core is placed near a telephone instrument or near one of the telephone wires, it picks up inductively both sides of the telephonic conversation without any electrical contact. A preamplif
Preamp Mixer Stomp-Box for Dobro Guitar
I designed and built this stomp-box forGrammy-winning resophonic guitar player Stacy Phillips. Stacy typically uses two transducers on his Dobro-style instruments: a piezo element mounted internally and a gooseneck-mounted electret microphone positioned an inch or so above the resonator cover. When I built this preamp in 1996, his microphone cons
LA4165M Memo REC Micro-cassette Player System With REC/PB Preamplifier ALC Circuit LED Driver Voice Sensor Power Amplifier (4?©) Governor
YD7312 DUAL RECORDING/PLAYBACK PREAMPLIFIER CIRCUIT WITH ALC
The YD9088 is a bipolar integrated circuit for use in mono portable and pocket Radios It is used when a minimum of peripheral components (of small dimensions and low costs) is important. The circuit contains a frequency-locked-loop (FLL) system with an intermediate Frequency (IF) of about 70kHz. Selectivity is achieved by active RC-filters. De-tun
Microphone preamplifier with audio compressor
Op-Amp Mic Preamp
A high quality microphone preamplifier using a single power supply, suitable for dynamic or electret microphones..
DIY phono preamp project
Originally posted by Justinasia What is the likely cost of the Aleph Ono, all the parts I mean? Anyone know? If it is the same as the Pearl but better ..
electret Mic preamp
Hi to all I`m new in the forum or better I have used it some ago to make a diy projector!I do not know electronics so much (I`m reading books and..
His Masters Noise: A Thoroughly Modern Tube Phono Preamp
even if I didn`t read thoroughly nice one almost enough xformers , but certainly not enough shunt regs..
Understanding the Music Man Stingray 2-band preamp
The schematic here is of the original Music Man Stingray bass guitar preamp. It runs off 9VDC and I have left off the voltage divider part of the..
Fender rhodes peterson vibrato preamp
There is considerable hiss brought on by the circuit. Cutting the treble knob helps greatly (but no fun with treble cut!). When the vibrato circuit is active, the his is worse. Following these discoveries, I re-capped the board given the schematic values as well as those shown on this picture: At this point I`ve only changed out the electrolytics.
Hammond C2 Organ preamp
So there I was, ripping out a solo during a practice on my ""new"" Hammond C2 organ and the sound falls away and gets soft to the point of no..
12AX7/12BH7 Hammond Tube Preamp Project
Build a preamp that I want to use to take a 1/4" keyboard line level signal and drive a Leslie 147 amplifier with it. I want to build the preamp using a 12AX7 and 12BH7 based on the design of a Hammond Organ preamp. Here is the schematic to the Hammond AO-28 Preamp I am going to build: I want to build from C6 to the output transformer. I don`t...
DIY CAT SL1 preamp
I build the CAT SL1 preamp with the attached schematic Noted that the gain of this circuit has about 26dB. I noted that the new SL1 have an option..
Tube preamp tone control
The +/- 3 dB point for the treble is about 2, 5 KHz, with about 12 dB boost/cut at 10 KHz. Perhaps you should check the wiring (again ) or perhaps componentvalues Do you have access to a signal generator yeah i checked wiring and components again and again, i used linear pots cuz there s no log pot here, but still it s not working, in fact the...
A Studio Preamplifier
The first was interested in a flexible preamp for use with a high-end acoustic guitar with piezo-electric bridge pickup, and the second wanted a preamp for use with a guitar emulator, to provide add someof the warmth that vacuum valves can provide. Both of these requirements, and very probably many more, can be met using a variation on The...
Class A-Designed Symmetrical Audio Preamplifier
The circuit was designed to produce a preamplifier with symmetrical audio input while the output operates in Class A type. Preamplifier (pre-amp) a devi..
Class A Modular Preamplifier with Single Integrated Circuit
The circuit was based on a single operational amplifier integrated circuit that is made to produce a modular preamplifier which functions in the Class A o..
Hi-Fi Phono Preamplifier with RIAA Specification
The circuit was designed according to the RIAA implementation of Hi-Fi phono preamplifier for the purpose of reproducing an audio from a moving magnet car..
Line Preamplifier Circuit with Tube Acquisition
The circuit was designed to create a line preamplifier by acquiring the use of double triode tubes. The circuit comprises of three parts, the main preampl..
Modular Buffer Preamplifier in Class A Operation
The circuit was designed to create a modular Class A buffer preamplifier in order to isolate stages in an audio circuit. BF245 a general purpose N-Chann..
Three ECC83-Based Tube Phono Preamplifier Circuits
The three circuits were based on the vacuum tube ECC83 designed to produce phono preamplifiers in compliance with the RIAA standards. Recording Industry A..
Balanced Microphone Preamplifier
The preamplifier is intended for use with dynamic (moving coilMC) microphones with an impedance up to 200 ? and balanced terminals. It is a fairly simple..
A popular project among microcontroller aficionados is to build a radio-controlled clock. Tiny receiver boards are available, with a pre-adjusted ferrite..
Electric Guitar Preamp Mixer and Line Driver
Depending on its design an electric guitar may have anything from one to six pickup elements. Classic (acoustic) guitars could also benefit from one or mo..
Modular Preamplifier Switching Center
Four high level inputs, Double Bar switching This module can be a necessary addition to the Modular Preamplifier Control Center when more than two sources..
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
Musical & Effects 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...
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