written by: Swagatam •edited by: Lamar Stonecypher•updated: 3/28/2013
It may be a daily soap or a live concert on the TV screen, the performance of the present circuit will certainly be able to give you a real theater like feel inside your home itself. Let's learn how to build a home theater system using ordinary electronic components.
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Today you will find the market crowded with a huge variety of home theater systems, but these are often too costly for each of us to own. The low cost versions do not reproduce a true theatre-like effect and thus can result in a total waste of money.
Many of us must have wondered how to build a home theater system that should not only be simple to build but also highly affordable.
The circuit design of a home theater system described here faithfully meets both the above mentioned criteria. Without wasting much of the time let’s get into the construction portion of the circuit.
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The functioning tips of the circuit described below will help you to clearly understand how to build a home theater:
The input audio is simultaneously applied to a couple of 741 op-amp ICs, which are configured as music and speech enhancers respectively.
This results in a bass boost of nearly15dB and a cut of 13dB at 100Hz, and a deep treble effect of 6dB and cut of 10dB at 15 kHz.
The enhanced bass is fed to a hi-power, hi-gain 50Watt power amplifier using IC TDA 1514.
It further boosts up the level to a mighty 82 dB strength and is responsible for a live theater-like performance through the woofer speakers.
The chiller effect or the treble is applied to another amplifier using IC TBA 820, which discretely sucks out the hi-frequency music part, for example the music from a violin or a guitar and is reproduced perfectly through the tweeters.
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Below given are the few points to help you go through the construction procedure:
It goes without saying that anybody who is intending to build this circuit should have a thorough knowledge of electronics and should know how to use a soldering iron.
Thus much explanation is not required as far as the circuit board assembly is concerned, only take care that the stuff is assembled cleanly, does not look messy and all the joints are put the right way as per the circuit schematic. The whole circuit should get accommodated on a 5"*5" piece of general purpose board.
The whole assembly may be fitted either inside a well finished wooden box or a metallic box of appropriate size which may be procured from the market.
Fix the controls in the given slots of the box. Also let the mains cord out of the box from the given rear side outlet.
Add an LED, fuse holder, and a toggle switch to the unit to make it look more attractive and complete.
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How to Test It?
Learning how to build a home theatre would be incomplete without knowing how to test it. The testing procedure is done through the following simple steps:
You will need a ready made speaker box consisting of a reasonably good quality woofer (12inches in diameter) and a tweeter fitted inside.
Connect the woofer and the tweeter wires to the appropriate inputs of the home theater system.
Keep all the controls to their minimum positions.
Connect an audio input to the home theatre system from the headphone socket of a television set.
Apply mains input to the circuit by inserting the mains cord into the mains socket.
Immediately you should be able to hear a hissing sound from the speakers.
Keeping the audio input on the lower side, switch ON the TV set.
An audio in the form of a speech or music should be instantly audible from the speaker box, but the response will be quite flat at this juncture!
Begin optimizing the controls by first gradually increasing the bass and the treble volume controls.
On doing this the audio volume should increase but still the depth will be missing!
Go on optimizing the controls by increasing the bass and treble effect… and wow! You should immediately start experiencing the theater like “roar" and reverb right away from the speaker output.
To get a stereo sound output, you will have to include two such identical circuits inside one box itself.
Positioning of the speakers will be a matter of a little experimentation. A correct orientation through trial and error of these according to the area of the hall can bring out a true live theatre-like surround sound effect.
To further know learn how to build a home theater from me, you may be able to contact me on my blog.