Circuit Wiring Solution

A very simple high efficiency 80W audio power amplifier project can be designed using the LM3875 power audio IC . LM3875 is a high-performance audio power amplifier capable of delivering 56W of continuous average power to an 8Ω load with 0.1% THD+N from 20Hz to 20kHz .
By connecting two LM39875 audio IC in bridge mode this audio power amplifier will deliver 80 watt of output power into an 8 Ohm load. The LM3875 IC devices should be suitably heatsinked.
As you can see in the circuit diagram , this power audio amplifier require few external electronic parts .

The LM3875 maintains an excellent signal-to-noise ratio of greater than 95dB(min) with a typical low noise floor of 2.0μV.
This 80W audio power amplifier module accepts a wide range input voltage from 20 up to 84 volts, but typically is recommended ( for this circuit ) a dual +/-25 volts DC power supply .
Some features of this 80W audio power amplifier project based on the LM1875 IC are :
output protection from a short to ground or to the supplies via internal current limiting circuitry ,output over-voltage protection against transients from inductive loads ,supply under-voltage protection .

Detects clipping in preamp stages, mixers, amplifiers etc., Single LED display – 9V Battery supply unit

This circuit was intended to be used as a separate, portable unit, to signal by means of a LED when the output wave form of a particular audio stage is “clipping” i.e. is reaching the onset of its maximum permitted peak-to-peak voltage value before an overload is occurring. This will help the operator in preventing severe, audible distortion to be generated through the audio equipment chain. This unit is particularly useful in signaling overload of the input stages in mixers, PA or musical instruments amplification chains, but is also suited to poweramplifiers. A careful setting of Trimmer R5 will allow triggering of the LED with a wide range of peak-to-peak input voltages, in order to suit different requirements. Unfortunately, an oscilloscope and a sine wave frequency generator are required to accurately setup this circuit. Obviously, the unit can be embedded into an existing mixer, preamp or power amplifier, and powered by the internal supply rails in the 9 – 30V range. The power supply can also be obtained from higher voltage rails provided suitable R/C cells are inserted. SW1 and B1 must obviously be omitted.

Circuit diagram:

Parts:

R1_______________1M 1/4W Resistor (See Notes)
R2,R3,R8_______100K 1/4W Resistors
R4,R6___________10K 1/4W Resistors
R5_______________5K 1/2W Trimmer Cermet or Carbon
R7_______________2K2 1/4W Resistor
R9______________22K 1/4W Resistor
R10______________1K 1/4W Resistor (See Notes)
C1,C4__________220nF 63V Polyester Capacitors
C2_______________4p7 63V Ceramic Capacitor (See Notes)
C3_____________220µF 25V Electrolytic Capacitor
C5______________10µF 25V Electrolytic Capacitor (See Notes)
D1,D2________1N4148 75V 150mA Diodes
D3______________LED (Any dimension, shape and color)
Q1____________BC547 45V 100mA NPN Transistor
IC1___________TL062 Dual Low current BIFET Op-Amp (or TL072, TL082)
SW1____________SPST Toggle or Slide Switch (See Text)
B1_______________9V PP3 Battery (See Text)

Circuit operation:

The heart of the circuit is a window comparator formed by two op-amps packaged into IC1. This technique allows to detect precisely and symmetrically either the positive or negative peak value reached by the monitored signal. The op-amps outputs are mixed by D1 and D2, smoothed by C4, R7 and R8, and feed the LED driver Q1 with a positive pulse. C5 adds a small output delay in order to allow detection of very short peaks.

Notes:

• With the values shown, the circuit can be easily set up to detect sine wave clipping from less than 1V to 30V peak-to-peak (i.e. 15W into 8 Ohms). If you need to detect higher output peak-to-peakvoltages, R1 value must be raised. On the contrary, if the circuit will be used to detect only very low peak-to-peak voltages, it is convenient to lower R1 value to, say, 220K omitting C2. In this way, the adjustment of R5 will be made easier.
• Using a TL062 chip at 9V supply, stand-by current drawing is about 1.5mA and less than 10mA when the LED illuminates. With TL072 or TL082 chips, current drawing is about 4.5mA and 13mA respectively.
• When using power supplies higher than 12V, the value of R10 must be raised accordingly.
• When using power supplies higher than 25V, the working voltage value of C5 must be raised to 35 or 50V.

Perhaps the surround amplifier circuit below is an interesting circuit is made. For, making easy just by using the IC and electrolytic capacitor added 1 , we already can hear the strains of music with sound ( Front Left ,Right and surround Right , Left. In addition to listening to music , this amplifier is also very suitable for gamers who want good sound quality.

Minimum voltage requred 9 volts and maximum of 15 volts. Power Output of each speaker 10 Watt with 4 ohm impedance.

The capacitor C1 controls low frequencies and capacitor C2 controls high frequencies.The schema ia basically a class B amplifier.The transistors 2N 3055 serves the function of driving the speaker.The other transistor functions as pre amplifiers for the driver stage.This is the basic scheme of the schema.The maximum power level of amplifier can be set by adjusting the 500 Ohm POT connected with the BC107 transistor.

Notes:

• The schema can be powered using a 50 V DC power supply with 5A current rating.Up to 60 v can be given to the schema.Any way the power supply must be well regulated and filters to avoid noise.
• Adjust the 500 ohm POT to obtain optimum performance.
• All capacitors must be rated higher than the supply voltage.
• Volume control can be attained by connecting a 10 K POT in series to the input of the amplifier.(Not shown in schema).

All the equipment installed in your car to play tracks through your stereo system is individually important. Component speakers or full-range speakers are there in your car to play your favorite tracks while doing justice to all the tunes. Naturally, the more you spend the more you are going to get a great result while there are some tips and tricks that can boost up sound production of your speakers at the same time as subwoofers are there to emphasis on bass. Baffles and foam placed between your speakers has great importance as well as they make sure the body of the car and speakers to not bump into each other all the time and producing noises that will be irritating to the ears. Enclosures that are box shaped to place your speaker’s in. the main function of these enclosures is to produce sound that is accurate and tight while they keep your speakers safe from dirt, prolonging their life.

The two kinds of enclosures that can be found in the market are sealed and ported enclosures. Like the name suggests, sealed enclosures are air tight making sure no air leaves or enters the box while ported enclosures have holes in front of the box to equalize pressure within and outside the box. This enclosure may increase the efficiency but the sound production is less accurate and tight than the sealed enclosure. The only thing that matter is that the different manufacturing of these enclosures do really make a difference in the sound production. If you want an enclosure for your speakers then Qlogic car audio enclosures is the best. Their carpeting around the box makes sure it keeps your speakers away from dirt while the box itself maximizes the productivity level. Now keeping in mind the importance and role played by the enclosures, these things come with the speakers themselves although you can pick from one of the types mentioned above according to your own taste and requirement. Sealed enclosures are actually easier to make yourself and produce sound that it should while ported are way complicated and do not have more fans. Qlogic also offers every other car audio accessories to jazz up your stereo system.

The thing that attracts every customer to purchase Qlogic car audio equipment is as they are way much cheaper with warranty and result that will make you its fan. The shipping for this product is very cheap than the rest of the electronic devices. The carpeting of Qlogic looks like they are made not just to play but to look good as well. The stylish styles and boxes will dazzle up your car interior as well. You can purchase this product from the links listed below.

http://www.qlogicenclosures.com/

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http://www.hifisoundconnection.com/

• Car Head Unit - Head unit is the core of a car audio system, part of the car audio system that plays sound. The continued development of technology makes the head unit is no longer only serve as a radio receiver FM / AM CD player and a player, some have additional functions to be able to play MP3s. There is also a car head unit that has the ability to play DVDs complete with monitors and can be connected with IPOD.
• Power Amplifier - The function of the power amplifier is to amplify the signal coming out of the head unit. In the world of various types of car audio power amplifiers are divided into several classes, such as class A, B, AB, and D. Each class power amplifier has the advantage that its usefulness can be tailored to our needs in building a car audio system. In addition to class division, the division of power amplifiers can also be seen from the number of channels (channels) and the amount of power generated by the power amplifier.
• Speaker - A device that functions convert electronic signals into audible sound. The speakers were divided into several parts / components, namely, subwoofers, woofers, mid-range, and tweeter. In order for speakers to work properly, required a series of electronic components that serves as a filter (cross over).
• Processor - With advances in technology processors play a significant role in a car system. Inside there is a processor features like time correction, cross-over-active, etc. equalizer. With the functions it will be very easy at the time of tuning car audioaudio system.