Identify diagram: audio

Showing posts with label audio. Show all posts

Sunday, 26 May 2013

Simple Audio Amp Circuit

This is an audio amplifier circuit.Here we have used femous Ic 741 as the pre amplifier.Ic 386 acts here as the Power amp.R3 resistor controls the volume.R2 contralls the gain.

Note

# This circuit operates with 9V

# Use 8ohm speaker for this

Friday, 17 May 2013

50 Watts Mosfet Audio Amplifier

The first stage of the amplifier is a differential amplifier based on transistors Q1 and Q2. Capacitor C8 is the dc input coupler, C1 R1 limits the input current and capacitor passes high frequency signals. The second stage is the stage driver consisting of transistors Q3 and Q4. Output stage is a complementary push-pull stage based MOSFETs IRF530 and IRF9530.Output attaches the loudspeaker with the inductor L1. Network consisting of R15 and C5 is designed to reduce noise. Capacitors C6 and C7 are the filters of the power supply. R6 is preset to adjust the quiescent current.

Friday, 12 April 2013

Simple Audio Power Meter Circuit

This simple circuit indicates the quantity of energy that goes to a loudspeaker. The dual-color LED presentations green at an applied energy degree of about 1 watt. At 1.5 watts it glows orange and above three watts it is vivid crimson. The circuit is attached in parallel with the loudspeaker connections and that is energyed from the audio signal. The further load that this characterizes is 470 Ohm (R1//R3) will no longer be a problem for any amplifier. During the positive 1 of 2 cycle of the output sign the inexperienced LED in the dual-color LED will probably be turned on, supplied the voltage is sufficiently excessive.

At better output voltages, T1 (depending on the voltage divider R2/R1) can begin to conduct and the fairway LED will go out. During the terrible half of cycle the red LED is driven by the use of R3 and can activate when the voltage is high enough. In the transition area (where T1 habitss extra and extra and ‘throttles’ the golf inexperienced LED as a result) the combination of red/green provides the orange colour of the dual-LED. By selecting appropriate prices for the resistors the facility stages will additionally be adjusted to suit.

Circuit diagram:

$\"simple-audio-power-meter-circuit-diagram1\"$ Audio Power Meter Circuit Diagram

The worths chosen here are for conventional lounge use. You will almost definitely be stunned at how loud you have to turn your amplifier up ahead of you get the LEDs to go! The resistors can be zero.25 W sorts, supplied the amplifier does now not ship greater than forty W constantly. Above this energy the transistor may not be that happy both, so watch out for that too. Because T1 is utilized in saturation, the gain (Hfe) is on no account important and any equivalent type can be used. The power degrees talked about are valid for 4-Ohm audio system. For 8-Ohm audio system the entire resistor values have to be divided by using two.

Tuesday, 9 April 2013

A Low Distortion Audio Pre amplifier

In an audio amplifier the quality of sound depends upon a number of factors, e.g. quality of active and passive components, circuit configuration, and layout. To an extent, the selection of components depends on the constructor’s budget. The discrete active components like transistors have been increasingly replaced by linear ICs, making the task of designer easier. With the passage of time, the general-purpose op-amps like LM741, which were being used in audio/hi-fi circuits, have become The preamplifier circuit presented here is based on a dual precision op-amp for the construction of a low distortion, high quality audio preamplifier.

Low Distortion Audio Pre-amplifier Circuit diagram:

A dual op-amp OPA2604 from Burr-Brown is used for all the stages. The FET input stage op-amp was chosen in this context it is worthwile to mention another popular bi-polar architecture op-amp, the NE5534A. It has, no doubt, an exceptionally low noise figure of 4nV/ÖHz but rest of the specifications compared to OPA2604 are virtually absent in this IC. Also This IC is also capable of operating at higher voltage rails of ± 24V (max.). Also its input bias current (100 pA) is many orders lower than its bipolar counterpart’s. This ensures a multifold reduction in noise.

A channel seperation of 142 dB exists between In the circuit, buffer is essential for the proper working of the subsequent blocks. A nominal input impedance of 47k is offered by this stage which prevents overloading of the preamplifier. The tone control is a baxandall type filter circuit.The bandwidth limiter is basically a low-pass filter with an upper cut-off ceiling at the end of the useful audio spectrum. The gain at 10 kHz is approximately 17 dB. The design is essentially 3-pole type and the upper frequency is set at 25 kHz. This lSetting the unit is fairly simple. Check the power leads feeding the IC for symmetrical voltages. High quality audio output from the line output socket is to be fed as the input signal to this preamplifier. Output of the preamplifier is fed to the power a The whole circuit consumes about 10 mA when the above-mentioned ICs are used. Power supply requirements are not critical as the circuit works on 7.5V to 15V DC..

Source : http://www.ecircuitslab.com/2012/01/low-distortion-audio-pre-amplifier.html

Saturday, 30 March 2013

Make a Single Chip Programmable Voice Audio Recorder Circuit

The article explains a single chip circuit which can be used for recording short voice clips or any audio clip ranging from 20 to 60 seconds. The incorporated IC APR9600 is a programmable voice recorder chip which facilitates infinite number of recording/erase of audio files in it as per user preference.

The recording or storage of the audio can be done through an integrated electret mic or via any line out or RCA port of an audio reproducing device.

However since the IC is a low bit device does not support Hi-Fi recording rather low quality music.

The sampling rate or the frequency response is limited to just 8 kHz max thats pretty ordinary if we compare it with the specs of modern Hi-Fi equipment.

Nevertheless, the IC is a stand alone device which does not depend on any external circuits, just plug it in, and it starts recording whatever voice data is fed across its input pins. Moreover since the data can be erased and refreshed any number of times, the unit becomes completely programmable and a pretty useful gadget.

Image courtesy: http://www.datasheetcatalog.org/datasheet/aplus/APR9600.pdf

Circuit Description

The proposed circuit of a programmable single chip voice recorder/player utilizes the IC APR9600 as the main processor of the circuit.

Its a 28 pin IC which can be very easily and quickly configured for getting the required results by adding a handful of common passive electronic components.

All the pin outs of the IC are specified by their individual functions, and the components are accordingly attached with the respective pinouts.

For example pin#28 and pin#27 are assigned as the trigger inputs for initiating playback and recording functions.

Sliding the connected switch toward right initiates the playback action while toggling it toward left puts the IC in the recording mode.

The IC also has appropriate visual indication options which provide the user with instant information regarding the position of the circuit.

The LED at pin#8 indicates the end of a playback file session.

The LED at pin#10 stays illuminated for so long the audio is being played, indicating circuit "busy"

The LED at pin#22 indicates through rapid flashes regarding the playback or recording modes of the IC.

The input data is normally picked from the mic which is appropriately connected across the pins 17 and 18 of the IC.

When the slider switch is pushed toward the recording mode, any audio entering the mic gets stored inside the IC until the specified time elapses.

The sampling rate of the IC can be set as per the user preference. Lower sampling rates will provide longer recording/playback periods and vice versa.

Longer periods would also mean lower voice quality while shorter periods of recording spec will produce relatively better sound processing and storing.

The entire circuit operates with a 5 volt supply which can be acquire through a standard 7805 IC after rectification from a standard transformer bridge capacitor network.

The audio output may be derived across pin#14 and ground which must be terminated to an audio amplifier so that the data can be heard with proper volume.

Thursday, 28 March 2013

10 to 14W Class A Audio Amplifier

I have built this amplifier and it does sound good. It requires a preamp as it hasnt got much gain. It requires big heat sinks and a large transformer and a great power supply and careful wiring, but in the end it is xtremely simple and it sounds very good. The zener diode rejects any ripple coming from the power supply, But you still only want a ripple of 10mV max. The ripple reaching the input is amplified, so the zener diode gets rid of that, but whatever ripple there is will still reach the power stage.