Introduction to Amplifier (Rise)

Amplification is the method of increasing the amplitude of a AC signal current or voltage such as audio signal for sound or video signal for a television picture. The amplifier allows a small input signal to control a bigger amount of power in the output circuit. The output signal is a replica of the original input signal but has higher amplitude.

Amplification is necessary as in most applications, the signal is weak to be used directly. For example, an audio output of 1mV from a microphone is unable to drive a loud speaker which requires a few volts to operate. Hence, the signal require to be amplified to a few volts before it can be fed in to the loud speaker.

NP N Transistor Circuit Configurations

An example of different type of transistor configurations in the circuit.

(1) The common emitter(CE) circuit makes use of emitter as its common electrode. The input signal is applied to the base and the amplified output is taken from the collector. This is the usually use because it's the best combination of current gain & voltage gain.

(2) The common base (CB) circuit makes use of base as its common electrode. The input signal is applied to the emitter & the amplified output is taken from the collector. The comparatively high emitter current compared to the base current ends in low input impedance value. For this reason, the CB circuit is never used.

(3) The common collector (CC) circuit makes use of collector as its common electrode. The input signal is applied to the base & the amplified output is taken from the emitter. This circuit is also called an emitter follower. This name means that the output signal voltage at the emitter follows the input signal at the base with the same phase but less amplitude. The voltage gain is less than one & is usually used for impedance matching. It's high input at the base as a load for the earlier circuit & low output impedance at the emitter as a signal source for the next circuit.

Classes

They can be classified in to classes A, B, C & AB. They are defined based on the percent of the cycle of input signal that can produce output current.

In Class A, the output current flows for the full cycle of 360 degree of input signal. The distortion is the lowest with around 5% to 10% &an efficiency of 20% to 40%. In general, most tiny signal operate class A

In Class C, the output current flows for less than half of the input cycle. Typical operation is 120 degree of input current in the coursework of the positive half cycle of the input current. This class has an efficiency of 80% but has the highest distortion. This class is usually used for RF amplification with a tuned circuit in the output.

In Class B, the output current flows for half of the input cycle which is around 180 degree. Class B operation lies between class A & class C. Classes B are usually connected in pairs & in such a circuit called push-pull amplifier. The push pull is often used for audio power output to a loud speaker.

In Class AB, it offers a compromise between the low distortion of class A & the higher power of class B. It is usually used for push pull audio power amplifiers.

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10 W Audio Amplifier Circuit Diagram

This design is based on the 18 Watt Audio Amplifier, and was developed mainly to satisfy the requests of correspondents unable to locate the TLE2141C chip. It uses the widespread NE5532 Dual IC but, obviously, its power output will be comprised in the 9.5 - 11.5W range, as the supply rails cannot exceed ±18V.

10 W Audio Amplifier Circuit Diagram

As amplifiers of this kind are frequently used to drive small loudspeaker cabinets, the bass frequency range is rather sacrificed. Therefore a bass-boost control was inserted in the feedback loop of the amplifier, in order to overcome this problem without quality losses. The bass lift curve can reach a maximum of +16.4dB @ 50Hz. In any case, even when the bass control is rotated fully counterclockwise, the amplifier frequency response shows a gentle raising curve: +0.8dB @ 400Hz, +4.7dB @ 100Hz and +6dB @ 50Hz (referred to 1KHz).

Notes:

    Can be directly connected to CD players, tuners and tape recorders.

    Schematic shows left channel only, but C3, C4, IC1 and the power supply are common to both channels.

    Numbers in parentheses show IC1 right channel pin connections.

    A log type for P2 will ensure a more linear regulation of bass-boost.

    Do not exceed 18 + 18V supply.

    Q3 and Q4 must be mounted on heatsink.

    D1 must be in thermal contact with Q1.

    Quiescent current (best measured with an Avo-meter in series with Q3 Emitter) is not critical.

    Set the volume control to the minimum and R3 to its minimum resistance.

    Power-on the circuit and adjust R3 to read a current drawing of about 20 to 25mA.

    Wait about 15 minutes, watch if the current is varying and readjust if necessary.

    A correct grounding is very important to eliminate hum and ground loops. Connect to the same point the ground sides of J1, P1, C2, C3 &C4. Connect C9 to the output ground.

    Then connect separately the input and output grounds to the power supply ground.

Parts:

P1_________________22K   Log.Potentiometer (Dual-gang for stereo)

P2________________100K   Log.Potentiometer (Dual-gang for stereo)

R1________________820R   1/4W Resistor

R2,R4,R8____________4K7  1/4W Resistors

R3________________500R   1/2W Trimmer Cermet

R5_________________82K   1/4W Resistor

R6,R7______________47K   1/4W Resistors

R9_________________10R   1/2W Resistor

R10__________________R22   4W Resistor (wirewound)

C1,C8_____________470nF   63V Polyester Capacitor

C2,C5_____________100µF   25V Electrolytic Capacitors

C3,C4_____________470µF   25V Electrolytic Capacitors

C6_________________47pF   63V Ceramic or Polystyrene Capacitor

C7_________________10nF   63V Polyester Capacitor

C9________________100nF   63V Polyester Capacitor

D1______________1N4148    75V 150mA Diode

IC1_____________NE5532    Low noise Dual Op-amp

Q1_______________BC547B   45V 100mA NPN Transistor

Q2_______________BC557B   45V 100mA PNP Transistor

Q3_______________TIP42A   60V 6A    PNP Transistor

Q4_______________TIP41A   60V 6A    NPN Transistor

J1__________________RCA audio input socket

Power supply parts:

R11_________________1K5  1/4W Resistor

C10,C11__________4700µF   25V Electrolytic Capacitors

D2________________100V 4A Diode bridge

D3________________5mm. Red LED

T1________________220V Primary, 12 + 12V Secondary 24-30VA Mains transformer

PL1_______________Male Mains plug

SW1_______________SPST Mains switch

Technical data:

Output power:

    10 Watt RMS into 8 Ohm (1KHz sinewave)

Sensitivity:

    115 to 180mV input for 10W output (depending on P2 control position)

Frequency response:

    See Comments above

Total harmonic distortion @ 1KHz:

    0.1W 0.009% 1W 0.004% 10W 0.005%

Total harmonic distortion @ 100Hz:

    0.1W 0.009% 1W 0.007% 10W 0.012%

Total harmonic distortion @ 10KHz:

    0.1W 0.056% 1W 0.01% 10W 0.018%

Total harmonic distortion @ 100Hz and full boost:

    1W 0.015% 10W 0.03%

Max. bass-boost referred to 1KHz:

    400Hz = +5dB; 200Hz = +7.3dB; 100Hz = +12dB; 50Hz = +16.4dB; 30Hz = +13.3dB

Unconditionally stable on capacitive loads

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18W Car Stereo Amplifier Circuit Diagram

This automobile stereo amplifier project is a class AB audio power amplifier using the Hitachi HA13118 module. It not only can be used in automobile application but also in any transportable or home amplifier process. It is simple to construct & has a maximum of outside parts. The module has a high power output from a low voltage supply using the bridge tied load system, & a high gain of 55dB.

This project will be useful in applications where the input signal is a low level, without requiring the use of a separate pre-amplifier. This IC module has a built in surge protection circuit, thermal shutdown circuit, ground fault protection circuit & power supply fault protection circuit making it reliable.

The Specifications of this project 
D.C. Input : 8 – 18V at 1-2 A

Power output : 18W maximum, 4 ohm load, 18V DC supply

S/N ratio : > 70 dB

THD : < 0.2% @ 1W

Freq. Response : ~ 30 Hz to 30 kHz, –3 dB

Input level : < 25 mV, for full output (G > 50dB)

Input Impedance : ~ 30 k ohm

The supply voltage necessary for this project is 8 -18V DC, at least one to two Amps. Maximum output power will only be obtained with a power supply of 18V at greater than two A, using a four ohm speaker. The power supply ought to be well filtered to reduce mains hum, a regulated supply will reduce noise even further. Additional filtering is unnecessary if operating from a battery supply.

Circuit Diagram Description

Most of the circuitry is contained within the amplifier module. C10 is the input coupling capacitor and blocks DC from the input. C11 bypasses any RF which may be present at the input. C1 & C2 provide an AC ground for the inverting inputs of the IC. R1/C7 and R2/C8 provide a high frequency load for stability with difficult speakers. C five & C six provide bootstrap feedback for the IC. C9 & C12 provide power supply filtering.

18W Car Stereo Amplifier Circuit Diagram

An externally mounted logarithmic potentiometer of between 10k ohm and 50k ohm, is used depending on the desired input impedance. The impedance ought to be keep as high as feasible for a guitar amp, unless using a separate pre-amp. Make sure-that the heat sink is mounted to the module.

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1 W Home Stereo Amplifier Circuit Diagram

This is a one watt home stereo amplifier module project using the KA2209 IC from Samsung, which is equivalent to the TDA2822. It operates from 3-12V DC & will work from a battery since the dormant current drain is low. It requires no heat sink for normal use. The input & output are both ground referenced. Maximum output will be obtained with a 12V power supply & 8 ohm speaker, however it is suitable for driving headphones from a supply as low as 3V.

The Specifications of the home stereo amplifier :

D.C. input : 3 – 12 V at 200 – 500 mA max
Idle current : approx. 10 mA
Power output : > 1 Watt max. 4-8 ohms, 12V DC
Freq. Resp. : approx. 40 Hz to 200 kHz, 8 ohm, G=10
THD : < 1 % @ 750 mW, 4-8 ohm, 12V
Gain : approx. x10 (20 dB) OR x100 (40dB)
S/N ratio : > 80 dB, G = 20 dB
Sensitivity : < 300 mV, G = 20 dB
Input Impedance : approx. 10 k ohm

Description 

The gain is adjustable from ten to 100, i.e. twenty to 40 dB. Start with feedback resistors R1 and R3 of 1k ohm, this will give a gain of ten which ought to be adequate for most applications. In case you need more gain, you can remove resistors R1 and R3.This will give a gain of about 100, or 40 dB.The input attenuation can be adjusted by the potentiometer which can be used as a volume control. The IC gain ought to be kept as low as necessary to accomplish full output, with the in put potentiometer and your signal source at maximum.

1 W Home Stereo Amplifier Circuit Diagram

Voltage Gain = 1+ R1/R2 = 1+R3/R4, however the maximum gain with no outside feedback is about 100, or 40dB. (GdB = 20log Gv)

This will keep the signal to noise ratio as high as feasible. Additional gain provided by the amplifier will reduce the S/N ratio by a similar amount, since the input noise figure is constant. Other values for R1 and R3 of between 1k and 10k ohm can be used if an intermediate gain level is necessary.

If driving a pair of headphones, you may also need a 100 ohm resistor in series with each output to reduce the output level, depending on headphone impedance & sensitivity. Make positive you start with the volume right down to check. Numerous headphones may be driven from the amplifier in the event you wish, since most headphones have at least 16 ohm impedance, or more often 32 ohm.

There are only a few outside parts, the IC contains most of the necessary circuitry. R1,R2 and R3,R4 are the feedback resistors. C1 provides power supply decoupling. C2 and C3 are the input coupling capacitors, which block any DC that might-be present on the inputs. C4,C5 block DC in the feed back circuit from the inverting inputs, and C6,C7 are the output coupling capacitors. C8, R5 and C9,R6 act as Nobel networks providing a high frequency load to maintain stability at frequencies where loud speaker inductive reactant may become excessive. The pot provides adjustable input level attenuation.

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100W Guitar Pre-Amplifier (Rise)

Introduction

Guitar amplifiers are always an fascinating challenge. The tone controls, gain & overload characteristics are individual, & the ideal combination varies from guitarist to the next, & from guitar to the next. There is no amp that satisfies everyone's requirements, & this offering is not expected to be an exception. The preamp is now at Revision-A, & although the whole schematic of the new version is not shown below, the essential characteristics are not changed - it still has the same tone control "stack" & other controls, but now has a second op amp to reduce output impedance & improve gain characteristics.

One major difference from any "store bought" amplifier is that in case you build it yourself, you can alter things to fit your own needs. The ability to experiment is the key to this circuit, which is although introduced in complete form, there is every expectation that builders will make modifications to suit themselves.

The amp is rated at 100W in to a four Ohms load, as this is typical of a "combo" type amp with 8 Ohm speakers in parallel. Alternatively, you can run the amp in to a "quad" box (four x 8 Ohm speakers in series parallel - see Figure five in Project 27b, the original editorial) and will get about 60 Watts. For the adventurous, two quad boxes and the amp head will provide 100W, but will be much louder than the twin. This is a common combination for guitarists, but it does make it hard for the sound man to bring everything else up to the same level.

The Pre-Amplifier

A picture of the Revision-A preamp is shown below. You'll see that there's dual op amps, but the schematic only shows. This is the main part of the Rev-A update - the output section now has gain (which is basically selected), and a better buffered low output impedance. The remainder of the circuit is unchanged.

The preamp circuit is shown in Figure one, and has a few fascinating characteristics that separate it from the "normal" - assuming that there is such a thing. This is simple but elegant design, that provides excellent tonal range. The gain structure is designed to provide a immense amount of gain, which is ideal for those guitarists who like to get that fully distorted "fat" sound.

However, with a couple of simple changes, the preamp can be tamed to suit any style of playing. Likewise, the tone controls as shown have sufficient range to cover very anything from an electrified violin to a bass guitar - The response can be limited in the event you wish (by experimenting with the tone control capacitor values), but I recommend that you try it "as is" before making any changes.

Figure 1 - Guitar Pre-Amplifier

Notes:

• IC pinouts are industry standard for dual opamps - pin 4 is -ve supply, and pin 8 is +ve supply.
• Opamp supply pins must be bypassed to earth with 100nF caps (preferably ceramic) as close as possible to the opamp itself.
• Diodes are 1N4148, 1N914 or similar.
• Pots should be linear for tone controls, and log for volume and master.

From Figure 1, you can see that the preamp uses a dual opamp as its only amplification. As shown, with a typical guitar input, it is possible to get a very fat overdrive sound, by winding up the volume, and then setting the master for a suitable level. The overall frequency response is deliberately limited to prevent extreme low-end waffle, and to cut the extreme highs to help reduce noise - not that it helps all that much, because with all that gain, noise is always going to be a problem.

Note:

The schematic has been modified slightly to improve the tone control performance (04 Jan 2002). A new schematic is now on line - the differences are relatively minor, but make the component values for the tone controls a bit cheaper (smaller value caps, and higher value pots). The power amp has been heavily revised, and the new version is also available.

If a really quiet amp is desired, you should substitute a 5532 dual opamp. These are more expensive (and harder to get), but will offer a substantial noise reduction. If you don't need all the gain that is available, simply increase the value of the first 4k7 resistor - for even less noise and gain, increase the second 4k7 as well.

If the bright switch is too bright (too much treble), increase the 1k resistor to tame it down again. Reduce the value to get more bite. The tone control arrangement shown will give zero output if all controls are set to minimum - this is unlikely to be a common requirement in use, but be aware of it when testing.

The diode network at the output is designed to allow the preamp to generate a "soft" clipping characteristic when the volume is turned up. Because of the diode clipping, the power amp needs to have an input sensitivity of about 750mV for full output, otherwise it will not be possible to get full power even with the Master gain control at the maximum setting.

Make sure that the input connectors are isolated from the chassis. The earth isolation components in the power supply help to prevent hum (especially when the amp is connected to other mains powered equipment).

UPDATES: I have had quite a few enquiries about the input connection setup. This is almost an industry standard, and is quite the opposite of what you might think it means. The same basic idea is used on Fender amps, as well as many others. The Hi input is used for normal (relatively low output) guitar pickups, and is "Hi" gain. Lo is 6dB less gain, and is intended for high output pickups so the first amplifier stage does not distort. The switching jack on the Hi input means that when a guitar is connected to the Lo input, it forms a voltage divider because the other input is shorted to earth. I hope this clears up any confusion (it will probably create more!).

I have also had several enquiries about the tone controls, one being that they don't do anything. If the preamp does not work properly, it is because it has been wired incorrectly - period! I know the circuit works, and it works very well, so please don't send e-mails claiming that it does not do what is claimed. For some reason, this project generates more e-mail than just about any other, and in all cases where I have had complaints, wiring errors have eventually been found.

The golden rule here is to check the wiring, then keep on checking it until you find the error, since I can assure you that if it does not work there is at least one mistake, and probably more.

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Simple 50-W Electronic Amplifier Circuit Diagram

This electronic amplifier project is an IC amplifier module from ST Microelectronics, the TDA7294. It is intended for use as a top quality audio class AB amplifier in hi-fi applications. It's low noise and distortion, wide bandwidth and nice output current capability, enabling it to supply high power in to both four ohm and 8 ohm lots. It's both short circuit and thermal protection.

With the addition of a handful of parts and an appropriate power supply, this module will deliver over 50W RMS in to four or 8 ohms-with < 0.1% Total Harmonic Distortion (THD) and < 0.1% Inter-modulation Distortion (IMD). It is also suitable as a replacement power amp stage, or upgrade for plenty of existing amplifiers of between 30W-50W, provided they have an appropriate dual supply, & most do.

The Specifications of the electronic amplifier project there are:

D.C. Input : 35V
Output power : > 50W RMS, 4-8 ohm load.
Gain : 24 dB (30dB modification)
Input sensitivity : one.3V for 50W, 8 ohm
Signal-to-Noise ratio : > 95 dB, (>105 dBA)
Frequency response : approx. 20Hz - 200kHz, �3 dB
Slew rate : > 10V/uS
THD : < 0.01%, 1W-40W, 1kHz
IMD : < 0.01%, 1W

The maximum supply voltage of the IC is +/- 40V. However the maximum dissipation of the IC can be exceeded even at a lower voltage. Therefore the supply voltage used require not be over +/- 35V. This can be constructed using a 50V middle tapped-transformer, a diode bridge rated at 5A (min.) & a pair of electrolytic capacitors, as shown below. A lower secondary voltage transformer could even be used but the reduced DC voltage will lead to less power output in to 8 ohms. You can still receive 50W in to four ohms with only 24V supply rails.

A 36V C.T. transformer will give you approx +/- 25V rails. The-mains transformer used ought to be rated at a maximum of 80VA. In the event you require to run modules in a stereo amplifier you can use a common power supply. In this case the transformer ought to be rated at 150VA or greater.

Electronic Amplifier Circuit Diagram Description

Most of the circuitry is contained within the IC module. The input signal is applied to pin three by capacitor C1 & low-pass filter R1/C2. The filter improves the pulse response & helps cease RF signals. The lower -3dB point is determined-by R2/C1 & R4/C3. This is about 20Hz for the values used. The upper -3dB point is over 200kHz. C7/C8 & C9/C10 provide additional power supply filtering or decoupling.

Simple 50-W Electronic Amplifier Circuit Diagram

 

R3/R4 are the feedback resistors. The gain is 1+R3/R4 which is approx 16 times, or 24dB. In case you need to increase the input sensitivity you may alter the resistors to suit. Changing R3 to 22k would increase the gain to 30dB and lower the input-required for 50W in to 8 ohm, to 0.6V, without affecting performance much. In case you reduce the worth of R4 you will also need to increase C3 to maintain bass response, as this sets the feedback low frequency roll off.

Pin ten is a mute input and pin 9 provides a standby mode. Muting ought to always happen before standby mode is selected. Connecting these pins permanently to the supply rail ensures that the amplifier comes on immediately on power up. Any switch-on clicks may be eliminated by increasing the time constants of R5/C4 and R6/C5 if necessary.

Make definite that a heavy duty heat-sink rated at least one.4 degree C/W or better is used.

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25-W Audio Power Amplifier Circuit Diagram

This audio power amplifier project is based on LM1875 amplifier module from National Semiconductor. It can deliver up to 30W of power using an 8 ohm load & dual 30V DC power supplies. It is designed to operate with maximum outside parts with current limit & thermal shutdown protection features . Other features include high gain, quick slew rate, wide power supply range, giant output voltage swing & high current capability.

Summary of the audio amply-fire features:

• Low distortion: 0.015%, 1 kHz, 20 W
• Wide power bandwidth: 70 kHz
• Wide supply range 16V-60V
• Up to 30 watts output power
• Internal output protection diodes
• Protection for AC & DC short circuits to ground
• 94 dB ripple rejection
• Plastic power package TO-220

25V Power Supply

The schematic below shows how the +25V DC & -25V DC are obtained. In order to provide power supply for two stereo amplifiers, a power transformer rating of 80VA with 240V/36V middle tapped secondary winding is used. The secondary output of the transformer is rectified by using 1N5401 diodes together with four electrolytic capacitors to smoother the ripple voltage. A fuse & a varistor are connected at the primary input to protect the circuit against power surge.

25-W Audio Power Amplifier Circuit Diagram

Audio Amplifier Module

The +25V & -25V DC power supply are connected to the audio amplifier module through a 2A fuse with the peripheral devices shown in the schematic below. The audio input signal to be amplified is coupled to pin one of LM1875 through the resistor R1 and electrolytic capacitor E5.

The output signal at pin four of LM1875 can be used to directly drive a 8 ohm loudspeaker. Resistor R6 and capacitor C5 prevent-the capacitance developed at the long speaker leads from driving the amplifier in to High Frequency Oscillation.

A heat-sink with a thermal resistance rating of one.4 Cecilius/Watt or better must be used or else the amplifier module will-be cut-off from operation due to the heat that will build up in the coursework of the operation of the amplifier. Take note that the heat sink tab on the IC module is internally connected to the -25V power supply hence it must be isolated from the heat sink by the use of an insulating washer. If this is not done, the negative rail will be shorted to ground.

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100 Watt Power Amplifier Circuit With IC TDA7294

Power Amplifier TDA7294 is a power amplifier with IC Power Amplifier is a mono 100W Class AB operation of OCL.

The power supply circuit. Positive, negative, and ground. Usually, we use the power supply circuit to + /-25V to + /-35V at 100W RMS will be used to heat sufficiently.

After many members have already made the TDA7294 as I know, with a sound quality that is the very gods or Hi-End itself.

Several days before the member’s PM to me saying that I had an amplifier using IC TDA7294 to have more of the same. Higher power. And low heat.

Achieved by increasing the voltage raising circuit For the more, it means high power and high heat up. Today I have come across. I use IC TDA7294 circuit at the time.

In-Home Use amplifier circuit is a Class G amplifier with low power consumption, resulting in the loss of a 20V DC power less.

And when you’re driving a high-power random access is party to a rhythm. Principles to do it. I took out a membership you can do is try to build up a bit.

We provides PCB both top and bottom side for you.

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Build 20W MOSFET Power Amplifier Circuit with IFR9520,IFR520

As we are like to show you about audio and sound circuit ,I found the circuit which is good one for power amplifier with one MOSFET.

The output power of an operational amplifier is often increased by a complementary emiter follower.

20W power amp MOSFET

It can also be done with a MOSFET,but it is not a good idea to connect such a device as a complementary souce follower because the maximum output voltage of the opamp is then reduced appreciably by the gate-source control voltage of the MOSFET ,which can be a couple of volts.

Another approach is to connect two MOSFETs as a complementary drain follower.The (alternating) output current provided by the MOSFETs is limited by the level of the supply voltages and the saturateion voltages of T3 and T4 Resistor R8,together with R9,provides feedback for both the opamp and MOSFETs .

The open-loop amplification of the opampis,therefore,increased by (1+R8/R9).the closed-loop amplification of the complete amplifier is (1+R3/R2).

The current source formed by T1 and T2 is required for arreanging the quiescent current of T3 and T4 at 50 mA.The values of resistors R4 and R5 are such that,without the current source the voltage drop across the resistor resulting from the direct current through the opamp is not sufficient to switch on T3 and T4 .with the current source,and depending on the setting of P1,the voltages across R4 and R5 rise,which increases the quiescent current through T3 and T4.

In view of the temperature dependence of the quiescent current,T2 must be mounted on the common heat sink(c. 5 K/W) of the MOSFETs.

The output power is not less than 20 W into 8 ohm,at which level the harmonic distortion amounts to 0.075 per cent at 100 Hz to 0,135 per cent at 10 kHz.

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Tiny Subwoofer Amplifier Circuit With UA741

 Tiny Subwoofer Amplifier Circuit With UA741

Sub-woofer circuit for you take it to apply with your sound system or devices as the device is small and few electronic part. We provides completed PCB and component layout.

 Mini Subwoofer Top PCB

We use the IC dual operational amplifiers TL072 in this circuit.

This subwoofer project is a subwoofer or a speaker to drive low frequencies, rank of 20 Hz to 150 Hz electronic circuit diagram below shows in details of a circuit and parts of the main amplifier UA741 for 22 watt in 4 ohm of car subwoofer driver and you can turn on VR50K for adjusted frequently of mini subwoofer .

The device is designed for an existing stereo amplifier, often requires adding another blow to the music of driving a subwoofer.

The amplifier uses BTL is a good and cheap ((Bridge Tied Load channels) 8-pin IC UA741 from Philips is now NXP Semiconductors, that may provide a small number of components and 22W at 4 ohm load voltage 12 volt car battery default.

 Mini Subwoofer Bottom Side

The mini subwoofer consists of several parts: the name of the potentiometer, dual-linear motion potentiometers, 1/4W resistors, capacitors, electrolytic 25V, 63V Polyester capacitors, 24 W BTL car radio RCA audio input amplifier and two speakers 4 ohm or 8 ohm woofers in isobaric parallel wiring.

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Simple 500W Audio Power Amplifier Circuit Diagram with Transistor

We take transistor MJL2194 and MJL2193 for drive output signal.so the amp has a capacity for enormous instantaneous current ability.

 500W Audio Power Amplifier Circuit Diagram

I think, it is useful for you to apply the circuit with your sound devices.

Circuit Functional
I use the -85 volt when the output current is supplied to the drive 350 to 340 very hot. Increase the output current, but it was too cold. The output to heat up faster than a normal open it. Sounds obvious, but sound quality is quite good.

I recomment it by turning out for the evening. If the drive is mounted on the metal part out.

I think simple. View full above, the observation that R 30 ohm then the voltage across the 0.86 V show that the new through its 29 mA if you add a file to / – 85 V, and suppose that the voltage across the component body. It was the same in both the R 30 ohm to get a very light 5 0.86 = 5.86 V and the current I will be 5.86/30 = 0.195 A = 195 mA, and the specification of mje340. mje350 get Ic (max) = 500 mA, so it is natural for it to heat up. Actually, it is not necessary to adhere to sync tr output should be interested in the following two tr power drive is better. For VR should be R300 .

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Build 10 Watt Audio Power Amplifier Circuit

10W Audio Power Amplifier Circuit

10W PA.The 10 watts power amplifier circuit by transistor describe here is an audio amplifier with output power of 10W.Used as a low frequency class AB Amplifier. Transistor has high output current and very low distortion.This 10W audio amplifier circuit diagram using Transistor is good for small room or car audio system.This circuit is a general-purpose 10W audio amplifier for moderate-power PA or modulator use in an AM transmitter.

With higher voltages and a change in bias resistors,up to 30 W can be obtained.

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Simple Tone Control Circuit with LM301A

This circuit and a simple series circuit Tone Control. This circuit tone control with surgical Amp LM301A. The JFET 2N3684 feature provides a high input impedance and low noise for UN buffer zone opinion operational amplifier operated EQ type. Could you see in detail of the circuit following thus as below.

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Simple 200W Audio Amplifier

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.

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