Digital Volume Control Circiuit

This is great opportunity to you.Because you can convert your old radio set.into a radio set with digital volume control.Here When you push S1 it increases the volume and when you press S2 It decrease the volume

Note

# Use DS1669 Ic for this circuit

# Supply voltage is 4.5v to 8v

# give the output of this circuit for the amp circuit

Simple Audio Mixer circuit

You can add some resistors in parallel connection for more audio input. To adjust the volume for each input channel, add linear trimmer or potentiometer with configuration: pin1> ground; pin2>output; pin 3>input

200w Audio Amplifier electronic circuit diagram

Description

Output Power : 200Watts
Load Resistance : 8ohms
Input impedance : 55K
Maximum supply voltage : (+95v)-0-(-95v)
Recommended supply voltage : (+66v)-0-(-66v)
This complete high quality, low noise mono audio power amplifier is based around the Hybrid Integrated Circuit STK4050 manufactured by Sanyo. The circuit incorporates volume and has a maximum music output power of 200W.The circuit incorporates an on board power supply; therefore, only centre tapped transformer is required to power the circuit. I t has very good quality sound. U can use it with your Home Theatre your PC & etc... You can also use it as Subwoofer Amplifier. It is a compact package for THIN-TYPE Audio sets. Easy Heatsink design to disperse heat generated in THIN-TYPE audio sets. Constant-Current circuit to Reduce supply switch-ON and switch-OFF shock noise. External supply switch-On and switch-OFF shock noise muting, Load short-circuit protection, thermal shutdown and other circuits can be tailored-designed.

300W Subwoofer Power Amplifier Wiring Diagram

300W Subwoofer Power Amplifier Wiring Diagram

Please agenda that the blueprint for this amp has been upgraded, and it is now recommended for connected aerial ability into 4 Ohms, but You will charge to go to extremes with the heatsink (fan cooling is awful recommended). It was originally advised for “light” alternate duty, acceptable for an equalised subwoofer arrangement (for archetype application the ELF assumption – see the Project Page for the advice on this circuit). Where connected aerial ability is required, addition 4 achievement transistors are recommended, active in the aforementioned way as Q9, Q10, Q11 and Q12, and application 0.33 ohm emitter resistors.

Continuous ability into 8 ohms is about over 150W (250W for ±70V supplies), and it can be acclimated after added transistors at abounding ability into an 8 ohm amount all day, every day. The added transistors are alone bare if you appetite to do the aforementioned affair into 4 ohms at best accumulation voltage! Do not alike anticipate about application food over ±70V, and don’t bother allurement me if it is ok – it isn’t!

The ambit is credible in Figure 1, and it is a analytic accepted design. Connections are provided for the Internal SIM (published abroad on the Project Pages), and clarification is provided for RF aegis (R1, C2). The ascribe is via a 4.7uF bipolar cap, as this provides lots of capacitance in a baby size. Because of the impedance, little or no abasement of complete will be apparent. A polyester cap may be acclimated if you adopt – 1uF with the nominal 22k ascribe impedance will accord a -3dB abundance of 7.2Hz, which is absolutely low abundant for any sub.

compact-disc-player-block-diagram

The bunched disc amateur contains two capital subsystems: the audio abstracts processing arrangement and the servo/control system. The servo, control, and affectation arrangement arrange the automated operation of the amateur and accommodate such items as the arbor motor, auto-tracking, lens focus, and the user interface. The audio abstracts processing area covers all added amateur processes. A block diagram of the bunched disc amateur is apparent in Figure 1.


Since the addition of the bunched disc amateur in 1982, the bazaar has apparent three ancestors of players. First bearing players were characterized by multi-bit DAC’s acclimated with brickwall about-face filters. Second bearing players acclimated the aforementioned multi-bit DAC’s but took advantage of agenda oversampling filters placed upstream of the DAC forth with a affable analog about-face filter. Finally, accepted players accomplish use of low-bit DAC’s forth with oversampling filters and the affable analog achievement filter. In the afterward sections, anniversary of these DAC types and clarification methods will be investigated

Simple Microphone Preamplifier

Simple Microphone Preamplifier

This simple microphone preamplifier circuit can use between your microphone and stereo amplifier. This amplifier microphone suitable for use with normal home stereo amplifier line/CD/aux/tape inputs. This microphone preamplifier can take both dynamic and electret microphone inputs (preamplifier provides power foe electret microphone elements).

This circuit idea is to keep the design as simple as possible to be easy to build. That was my goal when I needed a simple external microphone preamplifier for my mixer. The performance of the circuit is nothing superior but can be used with many not so serious projects.
Microphone Preamplifier Circuit Features

Brief description of operation: Simple microphone preamplifier
Circuit protection: No special protection circuits used
Circuit complexity: Very simple one transistor circuit
Circuit performance: Amplification 35 dB, flat frequency response from 20 Hz to 20 kHz, quite poor distortion performance figures, a little bit noisy
Availability of components: Uses common and easily available components
Design testing: I have built few microphone preamplifiers based on this circuit and theu have worked without problems.
Applications: Interface dynamic or electret microphone to a line level audio input in HIFI amplifier or computer soundcard.
Power supply: 9V battery, takes less than 10 mA current
Estimated component cost: Electronics components than $10
Safety considerations: No special electrical safety considerations.

The circuit is a simple one transistor amplifier with amplification of about 30-40 dB (depends on transitor, temperature and voltage). The dynamic mic input is just a simple one transistor amplifier circuit with nothing special in it. LED D1 is in the circuit to show that the circuit operates. The voltage drop caused by LED (around 1.8V for RED led) has been taten in account when designing the amplifier circuit built around Q1. Resistor R4 and capacitor C5 make a filter to filter out possible noise from battery or other power source which is used to feed this circuit. Capacitors C1, C2 and C3 are used to block the DC bias on Q1 base to flow out of microphone input to microphone (the polarity of all capactors is straigh line = + and curved line = -).

Electret microphone input has a resistor R1 fo feeding current through electret microphone capsule when it is connected to the electret microphone input. Electret microphone needs some current (about 1 mA) flowing through it to operate, because there is a small amplifier circuit inside the microphone capsule. This circuit is suitable for all typical cheap electret capsules which available from any electronic component shop. Because electret microphones have higher signal level output, it is quite easy to overdrive the amplifier when you shout to electret microphone.

The circuit is bet to build to a small metal box like in the picture above. Put the 9V battery inside the case too. Battery power and metal box keep external noise and interference sources away. I used standard 6.3 mm jack for dynamic microphone and 3.5 mm mono jack for electret micrphone both installed to from, panel of the metal box. The LED and power switches are also installed to front panel.

Home Stereo Amplifier Using STK4241V

Home Stereo Amplifier Using STK4241V

This home stereo amplifier circuit using STK4241V. This home stereo amp is equiped with STK4241V wich is a thick film hybrid IC, AF Power Amplifier (Split Power Supply) (120W+120W min, THD = 0.08%).

Some features of STK4241V


Muting circuit built-in to isolate all types of shock noise.
Current mirror circuit for low 0.08% total harmonic distortion

For this 2×120W home stereo power audio amplifier we use a single monochip STK4241V to obtain up to 120W for each channel.

Printed Circuit Board (PCB) of Home Stereo Amplifier STK4241V
STK4241V Stereo Amplifier Parts List
R6, R22 – 560 ohm / 0.125W
R1, R24 – 1K / 0.125W
R9, R10 – 1K / 0.5W
R7, R18 – 4.7K / 0.25W
R8, R19 – 4.7K / 0.5K
R2, R5, R21, R23 – 56K / 0.125W
C7, C17 – 3pF ceramic
C2, C20 – 470pF ceramic 50V
C6, C16 – 1nF 100V
C11, C12 – 100nF 100V
C1, C19 – 2.2uF 50V
C5, C15 – 1uF 63V
C4, C10, C13 – 10uF 63V
C9, C14 – 47uF 63V
C8, C18 – 100uF 16V

audio-detector-circuit

This electronic detector circuit is to do audio detection. The circuit is for detecting one of those 3.6khz (approx) beepers from Radio Shack. The component used is a single IC (LM324 quad op amp) and a handful of parts.
Notes

The capacitor and resistor on the output of the peak detector are selected to give a reasonable decay time. I.e. so a single pulse doesn't stretch out and be miss-interpreted as an audio signal. I think I sample the output at 100ms intervals and signal a valid sound if three consecutive samples are true.
The only critical parts are the trimmer, capacitors and the 560 ohm resistor in the band pass filter. The diode is not critical: any small diode will do fine.
The trimmer is used to set the center frequency. I just run the beeper and adjust for the strongest output signal.
It uses a condenser mic, surplus. Probably any computer microphone will do. The 4.7K resistor is a typical load for those things

12Volt Audio Amplifier IC TDA7222AP

This is the circuit diagram of a 6W audio power amplifier using the IC TA7222AP. IC TDA7222AP is an excellent integrated audio amplifier which can deliver 5.8W to a 4 Ohms load at 12V supply voltage. The IC has very good features like, muting function, low distortion, high ripple rejection, short circuit protection, thermal shut down etc. This amplifier can be operated from 8 to 12V and this makes it ideal for car radio applications.

Note

Use 12V DC for powering the circuit.
The IC must be heatsinked.
Speaker can be a 4 ohms one.
For optimum performance input and output must be separately grounded.

TA7222AP pin out


Pin Name Description
1 Vcc Supply Voltage
2 RR Ripple Reject
3 MC Muting control
4 OP AF Signal Input
5 FB FB Filter
6 GA Gain adjust
7 GND Ground
8 GND Ground
9 OP AF Output
10 BS BootStrap
.

Audio Amplifier 4 Transistor

The circuit a 4-transistor amplifier suitable for a variety of projects including receivers, intercoms, microphones, telephone pick-up coils, and general audio monitoring. The amplifier has a power isolation circuit and bandwidth limiting to reduce oscillations and “motorboating”. The values are not particularly critical and modest deviations from the indicated values will not significantly degrade the performance.

Three cell battery packs giving about 4.5 volts are recommended for most transformerless audio amplifiers driving small 8 ohm speakers. The battery life will be considerably longer than a 9 volt rectangular battery and the cell resistance will remain lower over the life of the battery resulting in less distortion and stability problems.

The amplifier may be modified to work with a 9 volt battery if desired by moving the output transistors’ bias point. Lowering the 33k resistor connected from the second transistor’s base to ground to about 10k will move the voltage on the output electrolytic capacitor to about 1/2 the supply voltage. This bias change gives more signal swing before clipping occurs and this change is not necessary if the volume is adequate.

60watt Amplifier Mosfet IRFP240-IRFP9240

The following is a 60 - 90W High Quality power amplifier. Circuit topology is about the same of the above mentioned amplifier, but the extremely IRFP9240 Rugged IRFP240 MOSFET devices and are used as the output pair, and well Renowned high voltage Motorola's transistors are employed in the preceding stages. The supply rails prudentially voltage was kept at the rather low value of + and - 40V. For those wishing to experiment, the supply voltage rails could be raised to + and - 50V maximum, allowing the amplifier to approach the 100W into 8 Ohm target

Note:

A small, U-shaped heatsink must be fitted to Q6 & Q7.
Q8 & Q9 must be mounted on large heatsinks.
Quiescent current can be measured by means of an Avo-meter wired in series to the positive supply rail and no input signal.
Set the Trimmer R10 to its minimum resistance.
Power-on the amplifier and adjust R10 to read a current drawing of about 120 - 130mA.
Wait about 15 minutes, watch if the current is varying and readjust if necessary.


List Component:

R1______________47K 1/4W Resistor
R2_______________4K7 1/4W Resistor
R3______________22K 1/4W Resistor
R4_______________1K 1/4W Resistor
R5,R12,R13_____330R 1/4W Resistors
R6_______________1K5 1/4W Resistor
R7______________15K 1/4W Resistor
R8______________33K 1/4W Resistor
R9_____________150K 1/4W Resistor
R10____________500R 1/2W Trimmer Cermet
R11_____________39R 1/4W Resistor
R14,R15___________R33 2.5W Resistors
R16_____________10R 2.5W Resistor
R17_______________R22 5W Resistor (wirewound)
C1_____________470nF 63V Polyester Capacitor
C2_____________470pF 63V Polystyrene or ceramic Capacitor
C3______________47µF 63V Electrolytic Capacitor
C4,C8,C9,C11___100nF 63V Polyester Capacitors
C5______________10pF 63V Polystyrene or ceramic Capacitor
C6_______________1µF 63V Polyester Capacitor
C7,C10_________100µF 63V Electrolytic Capacitors
D1___________1N4002 100V 1A Diode
D2_____________5mm. Red LED
Q1,Q2,Q4_____MPSA43 200V 500mA NPN Transistors
Q3,Q5________BC546 65V 100mA NPN Transistors
Q6___________MJE340 200V 500mA NPN Transistor
Q7___________MJE350 200V 500mA PNP Transistor
Q8___________IRFP240 200V 20A N-Channel Hexfet Transistor
Q9___________IRFP9240 200V 12A P-Channel Hexfet Transistor

25Watt Audio Amplifier Mosfet IRF530-IRF9530

The following is a circuit of 25Watt High Quality power amplifier Mosfet IRF530-IRF9530 from Motorola's transistors are employed in the preceding stages. The supply rails prudentially voltage was kept at the rather low value of + and - 32V.

Note:

Q6 & Q7 must have a small U-shaped heatsink.
Q8 & Q9 must be mounted on heatsink.
Adjust R11 to set quiescent current at 100mA (best measured with an Avo-meter connected in series to Q8 Drain) with no input signal.
A correct grounding is very important to eliminate hum and ground loops. Connect to the same point the ground sides of R1, R4, R9, C3 to C8. Connect C11 to output ground. Then connect separately the input and output grounds to power supply ground.


List Component

R1,R4_________47K 1/4W Resistors
R2____________4K7 1/4W Resistor
R3____________1K5 1/4W Resistor
R5__________390R 1/4W Resistor
R6__________470R 1/4W Resistor
R7___________33K 1/4W Resistor
R8__________150K 1/4W Resistor
R9___________15K 1/4W Resistor
R10__________27R 1/4W Resistor
R11_________500R 1/2W Trimmer Cermet
R12,R13,R16__10R 1/4W Resistors
R14,R15_____220R 1/4W Resistors
R17___________8R2 2W Resistor
R18____________R22 4W Resistor (wirewound)
C1___________470nF 63V Polyester Capacitor
C2___________330pF 63V Polystyrene Capacitor
C3,C5________470µF 63V Electrolytic Capacitors
C4,C6,C8,C11_100nF 63V Polyester Capacitors
C7___________100µF 25V Electrolytic Capacitor
C9____________10pF 63V Polystyrene Capacitor
C10____________1µF 63V Polyester Capacitor
Q1-Q5______BC560C 45V 100mA Low noise High gain PNP Transistors
Q6_________BD140 80V 1.5A PNP Transistor
Q7_________BD139 80V 1.5A NPN Transistor
Q8_________IRF530 100V 14A N-Channel Hexfet Transistor
Q9_________IRF9530 100V 12A P-Channel Hexfet Transistor

12Volt Audio Amplifier Menggunakan Transistor

This circuit power amplifier was deliberately designed using no ICs and in a rather old-fashioned manner in order to obtain good harmonic distortion behavior and to avoid hard to find components. The amplifier(s) can be conveniently supplied by a 12V wall plug-in adapter. Closing SW1 a bass-boost is provided but, at the same time, volume control must be increased to compensate for power loss at higher frequencies. In use, R9 should be carefully adjusted to provide minimal audible signal cross-over distortion consistent with minimal measured quiescent current consumption; a good compromise is to set the quiescent current at about 10-15 mA.To measure this current, wire a DC current meter temporarily in series with the collector of Q3.

List Component

P1_____________10K Log.Potentiometer
R1,R2__________33K 1/4W Resistors
R3_____________33R 1/4W Resistor
R4_____________15K 1/4W Resistor
R5,R6___________1K 1/4W Resistors
R7____________680R 1/4W Resistor
R8____________120R 1/2W Resistor
R9____________100R 1/2W Trimmer Cermet
C1,C2__________10µF 63V Electrolytic Capacitors
C3____________100µF 25V Electrolytic Capacitor
C4,C7_________470µF 25V Electrolytic Capacitors
C5_____________47pF 63V Ceramic Capacitor
C6____________220nF 63V Polyester Capacitor
C8___________1000µF 25V Electrolytic Capacitor
D1___________1N4148 75V 150mA Diode
Q1____________BC560C 45V 100mA PNP Low noise High gain Transistor
Q2____________BC337 45V 800mA NPN Transistor
Q3____________TIP31A 60V 4A NPN Transistor
Q4 ___________TIP32A 60V 4A PNP Transistor
SW1___________SPST switch

TL072 Audio Amplifier

This TL072 power amplifier circuit providing an ac voltage gain of 4, in order to drive less sensitive power amplifiers. As modern Hi-Fi home equipment is frequently fitted with small loudspeaker cabinets, the bass frequency range is rather sacrificed. This circuit features also a bass-boost, in order to overcome this problem. You can use a variable resistor to set the bass-boost from 0 to a maximum of +16dB @ 30Hz. If a fixed, maximum boost value is needed, the variable resistor can be omitted and substituted by a switch.

Skema Rangkaian TL072 Audio Power Amplifier



Note:

A log type for P2 ensures a more linear regulation of bass-boost.
Please note that, using SW1, the boost is on when the switch is open, and off when the switch is closed.

List Component:

P1_________________10K Log.Potentiometer
P2________________100K Log.Potentiometer
R1,R2_____________100K 1/4W Resistors
R3,R6______________15K 1/4W Resistors
R4_________________10K 1/4W Resistor
R5_________________22K 1/4W Resistor
R7__________________1K 1/4W Resistor
R8________________560R 1/4W Resistor
C1,C2,C5____________2µ2 63V Electrolytic Capacitors
C3________________470µF 35V Electrolytic Capacitor
C4__________________1µF 63V Polyester Capacitor
C6_________________47nF 63V Polyester Capacitor
C7_________________22µF 25V Electrolytic Capacitor
IC1_______________TL072 Dual BIFET Op-Amp

Add an effective New Dimension to your Stereo sound

Add an effective New Dimension to your Stereo sound, "Increase Seperation and Reduce Noise".

Sound Controlled Filp Flop

Described here is a very inexpensive solution to many phono-controlled applications like remote switching on, for instance, or activating a camera, tape recorder, burglar alarms, toys, etc. The circuit given here employs a condenser microphone as the pick-up. A two-stage amplifier built around a quad op-amp IC LM324 offers a good gain to enable sound pick-up upto four metres. The third op-amp is configured as a level detector whose non-inverting terminal is fed with the amplified and filtered signal available at the output of the second op-amp. The inverting input of the third op-amp is given a reference voltage from a potential divider consisting of a 10k resistor and a 4.7k preset. The 100-ohm resistance in series with the potential divider ensures against the mis-triggering of the circuit by noise. Thus by adjusting the preset one can control the sensitivity (threshold) of the circuit. The sensitivity control thus helps in rejecting any external unwanted sounds which may be picked up by the amplifier. The output of the level detector are square pulses which are used to trigger a flip-flop. The 100mF capacitor connected across the supply also helps in bypassing noise.
A well regulated supply is recommended for proper functioning of the circuit because an unregulated supply can cause noise pulses to appear in the supply rails when the circuit changes-over state (especially when a load is connected to the circuit). These pulses can be picked up by the sensitive amplifier which will cause the circuit to again switch-over states, resulting into motor-boating noise.
Since the circuit operates at 4.5V, it can be easily incorporated in digital circuits. Fig. (b) shows how the circuit can be employed to control the direction of a DC motor. The circuit employs four npn transistors. Transistors T1 and T4 have their bases tied together and they switch-on simultaneously when Q output is logic 1. Similarly T2 and T3 conduct when Q output is logic 1. Thus current through the motor changes direction when the flip-flop toggles. Filters connected in the circuit and tuned to different bands of audio frequencies will enable the same circuit to control more than one device. For instance, a high frequency sound (such as whistle) can switch on device 1 and a low frequency sound (such as clapping) can control device 2.

3-state sound generator with LM556

LM556 is a dual timer that can be operated as two LM555.
The two timers operate independently of each other sharing only VCC and ground.You can define timing by provide an external resistor and capacitor for each timer.

This circuit is a 3-state sound generator.The IC is defined to generate audio frequency one for high audio frequency and one for low audio frequency .

You can use this tool to obtain the values of R and C for your desire sound.

When S1 was selected for each position the sound will generated by

1. Two tone
2. Steady tone
3. Tone burst

8watt audio power amplifier

The LM383 is a cost effective, high power amplifier suited
for automotive applications. High current capability (3.5A)
enables the device to drive low impedance loads with low
distortion. The LM383 is current limited and thermally protected.
High voltage protection is available (LM383A) which
enables the amplifier to withstand 40V transients on its supply.
The LM383 comes in a 5-pin TO-220 package

This circuit can use with 4 ohms speaker.LM383 MUST be installed on a heat sink.

Three-Level Audio Power Indicator

Parts:

R1__________100K 1/4W Resistor
R2___________50K 1/2W Trimmer Cermet
R3__________330K 1/4W Resistor
R4____________1M2 1/4W Resistor
R5__________470K 1/4W Resistor
R6,R7_______500K 1/2W Trimmers Cermet
R8____________1K5 1/4W Resistor
R9-R11______470R 1/4W Resistors

C1___________47pF 63V Ceramic Capacitor
C2__________100nF 63V Polyester Capacitor
C3___________47΅F 25V Electrolytic Capacitor
C4____________1΅F 25V Electrolytic Capacitor

D1______BZX79C5V1 5.1V 500mW Zener Diode
D2_________1N4148 75V 150mA Diode
D3-D5________3mm. Yellow LEDs

IC1_________LM339 Quad Voltage Comparator IC

SW1__________SPST Slider Switch

B1_____________9V PP3

Clip for 9V PP3 Battery


Circuit operation:

This circuit is intended to indicate the power output level of any audio amplifier. It is simple, portable, and displays three power levels that can be set to any desired value. For a standard HiFi stereo power amplifier like the 25W one described in these pages, the power output values suggested are as followings:

D5 illuminates at 2W

D4 illuminates at 12.5W

D3 illuminates at 24.5W

The above values were chosen for easy setup, but other settings are possible.
IC1A is the input buffer, feeding 3 voltage comparators and LEDs drivers by means of a variable dc voltage obtained by R5 and C4 smoothing action. In order to achieve setting stability, the supply of IC1 and trimmers R6 & R7 is reduced and clamped to 5.1V by Zener diode D1.

Notes:

The simplest way to connect this circuit to the amplifier output is to use a twisted pair cable terminated with two insulated crocodile clips.

Setup is best accomplished with an oscilloscope or an audio millivoltmeter like the one described in these pages.

A 1KHz sine wave generator with variable output is also required (see a suitable circuit in this website also).

Connect the generator to the amplifier input and the Audio Power Indicator to the output of the amplifier, in parallel with the oscilloscope probe or the audio millivoltmeter input.

When using high power outputs disconnect the loudspeakers to avoid Tweeters damage and connect in their place an 8 Ohm 20-30 Watt wirewound resistor.

Remember that VRMS output is equal to output Peak-to-Peak Voltage divided by 2.828.

RMS power output in Watts is equal to VRMS2 divided by speaker impedance (usually 8 or 4 Ohms).

Example: set the output of the 1KHz sinewave generator to read 14V on the audio millivoltmeter (24.5W 8 Ohms). Set R2 until D3 illuminates, and be sure that D3 turns-off when diminishing a little the generator's output.

Do the same with R7 for D4 and R6 for D5. The readings of the audio millivoltmeter must be 10V (12.5W 8 Ohms) and 4V (2W 8 Ohms) respectively

2N3055 Power Amplifier

Simple and low cost. The optimal supply voltage is around 50V, but this amp work from 30 to 60V. The maximal input voltage is around 0.8 - 1V. As you can see, in this design the components have a big tolerance, so you can build it almost of the components, which you find at home. The and transistors can be any NPN type power transistor, but do not use Darlington types... The output power is around 60W.


Some comments:
- capacitor C1 regulates the low frequencies (bass), as the capacitance grows, the low frequncies are getting louder.
- capacitor C2 regulates the higher frequencies (treble), as the capacitance grows, the higher frequencies are getting quiter.
- this is a class B amplifier, this means, that a current must flow through the end transistors, even if there is no signal on the input. This current can be regulated with the 500Ω trimmer resistor. As this current incrases, the sound of the amplifier gets better, but the end transistors are more heating. But if this current decrases, the transistors are not heating so much, but the sound gets worse