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diy microphone preamp
the octal phono preamplifier
Octal Preamplifier can also be built as a stand alone unit without the linestage part. This is not feasable since it has a split RIAA, which means the RIAA EQ circuit is split into two parts, one after the first stage and another one after the second. This means the second RIAA part`s accuracy depends on the loading resistor that follows after...
The circuit is so simple that there is little to say about it, but it gives very good results. Tr1 is operated in grounded base mode with input to its emitter to give low impedance input. The values shown give correct operation from 9v. If operating from other voltages you may wish to alter the 1K8 resistor to give symmetrical clipping at high lev
mic preamp circuit
ART TPS2 is a starved tube mic preamp. One 12AX7 tube operating at about 50v plate voltage to add color to the sound. As I intended to build a all solid state preamp, the 12AX7 and its peripheral component were removed. The right channel input stage is mostly the original TPS2 capacitor input discrete differential stage. The major change is that t
preamp mic schematic
audio preamplifier with tone control
echo repeter and preamp mic schematic
head preamplifier circuit
hi fi phono preamp circuit
low noise balanced microphone preamp
phono preamp circuit
preamp mic schematic and audio megaphone
stereo audio preamp schematic
After the unexpectedly big success of my JFET bass preamp I decided to build an onboard version. For a Jazz Bass-like instrument, I had to get along with three controls, maybe some switches if I used push-pull pots. Further, I wanted the functions of the knobs unchanged (vol - vol - tone) and, if possible, use the original pots. This preamp featur
pt05 diy preamplifier
The next stage is working with the first stage as well it is a fully-complementary. The cascode circuit is also in this place to improve linearity of the amplifiers. Cascode circuit requires a constant reference voltage biasing to make a cascode transistor on. We chose to use a transistor array as a voltage reference. Because it requires less curr
My CM7777 preamp has failed. I want to determine if the failure is due to the power supply or the preamp itself. Does the power supply output a DC voltage on the ..
Design and Dimensioning of Aktive Low-Pass and High-Pass Filters. Sallen-Key and Multiple Feedback Topologies, Spice Netlist Generator..
The PZP-1 Piezo Buffer is now available! The PZP-1 is a high impedance buffer preamp, using 100% discrete class-A circuitry. Designed expressly for the Fender Precision acoustic/electric and HMT basses, it can also help other instruments with piezoelectric pickups. If you thought piezo pickups had to sound "clacky", weak, and trebly, think agai
The input transistor Q2 is an N-channel JFET. Each particular JFET sets a particular output bias voltage, so the JFET must be selected from among multiple devices for the desired bias value. Fortunately, due to the low current involved, desirable devices can come from a wide range of device types. JFETs also vary with respect to gain and noise lev
modular class a buffer preamplifier
A unit which is often very useful, if we need to isolate, in sound circuits, two stage between them. Then we can use this circuit which has an amplified unit, which gain X1, we do not use total negative feedback, only local, with the result that distortion remains at a very low level. Matching must be done with great care to the types of...
symmetrical preamplifier class a
This is a symmetrical amplification unit circuit, more composed, modified by a construction which was proposed some years ago by Lisley Hood. The most important reason is to get the right transistor FET at differential amplifier at input. In spite of all this it is a circuit which provides, current mirror stage of both sides, with the result of...
symmetrical class a preamplifier
A very simple but very good amplifier unit, with low distortion. A similar modification was used as a preamplifier HAFLER. The quality however of the reproduced sound in all the symmetrical amplifiers regardless of the cost of the necessary materials, transistors, capacitor and resistors..
portable microphone preamplifier
This circuit is mainly intended to provide common home stereo amplifiers with a microphone input. The battery supply is a good compromise: in this manner the input circuit is free from mains low frequency hum pick-up and connection to the amplifier is more simple, due to the absence of mains cable and power supply..
moduler preamplifier circuit diagram
To complement the 60 Watt MosFet Audio Amplifier a High Quality Preamplifier design was necessary. A discrete components topology, using + and - 24V supply rails was chosen, keeping the transistor count to the minimum, but still allowing low noise, very low distortion and high input overload margin. Obviously, the modules forming this...
portable microphone preamplifier circuit schematic
This circuit is mainly intended to provide common home stereo amplifiers with a microphone input. The battery supply is a good compromise: in this manner the input circuit is free from mains low frequency hum pick-up and connection to the amplifier is more simple, due to the absence of mains cable and power supply. Using a stereo microphone the...
Now day`s audio signal preamp is used in many electronic devices. There are many types of audio preamp circuits from simple to complicated big circuits. Here we are showing you a very good design of a small circuit of signal preamplifier. circuit is best for providing extra gain to weak audio signals. In this circuit the transistor used is a high
microphone preamp circuit
Here is a schematic of a very sensitive microphone preamp circuit, which can be used to increase gain of microphone or boost the audio signals coming from microphone. The circuit is very simple contains only few components and can be assembled in few minutes if all parts are available. This is a versatile mic preamp circuit and can be used for man
3 input microphone preamplifier
The circuit given here is of a three input mic mixer cum preamplifier using the IC LM348. The LM348 is a high gain, internally compensated quad operational amplifier with a class AB output stage. The IC has very low input supply current drain (0. 6mA/ opamp) and operates from a dual power supply. Out of the four op-amps inside the IC LM348, IC1a, I
Crystal pickup pre-amplifier circuit
A preamplifier operating on a single supply and suitable for use with high impedance type crystal pickups is shown here. The circuit is basically a non-inverting AC amplifier in which the gain is dependent on the feedback resistor R4. The smaller is the R4, the lower will be the gain. The low frequency roll off characteristics are decided by C3....
Audio Filters Circuits
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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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