The article discussed here provides a simple, cheap home theater system circuit that may be built at home and used for the desired purpose.
Introduction
The results from this circuit design are outstandingly rich and have the capabilities comparable with the costly hi-end types available in the market.
Home theater systems are quite common nowadays and probably every one of us has one in their homes.
However most of you might be quite unsatisfied by the results of these commercial brands and makes, or probably many of you are completely unaware of what a truly efficient home theater system really sounds like.
Let’s study the design elaborately with the following points:
Basically the circuits discussed are all active tone controller configurations designed for controlling different frequency bandwidth discretely and reproduce the outputs at the respective speakers.
The speakers are also specifically chosen and integrated with the relevant stages for acquiring the most optimized results.
Looking the shown circuit above, the design is a typical tone controller circuit, having discrete bass and treble controls.
The first section incorporates a transistor which solely becomes responsible for the required frequency dimensioning functions. The relevant pots are used for getting the desired bass and treble enhancement effects from the circuit.
How the Circuit Functions
The CIRCUIT DIAGRAM is pretty simple and yet provides very cut and boost with the relevant bandwidths. The second stage which utilizes the IC 741 is also a bass, treble control circuit, however since an IC is used the effects become much enhanced than the previous stage and again the results can be discretely monitored and implemented using the relevant pots associated with the circuit.
It can be clearly seen that the above discussed two stage are connected in series. It means the obtained music and speech enhancing features from the individual units now become intensified to much sharper and magnified extents, but the results still are quite controllable to the desired any desired limits using the four pots associated with the individual stages.
The above units may be optimized to receive audio outputs having intense and heavy bass effects or the results may be trimmed to highlight extreme “chilling” treble effects from the outputs.
Two of the above circuit assemblies may be built separately for making the ultimate home theater system circuit, meaning you will finally have eigt pots to control for achieving any desired levels of optimized sound levels. The above units need to be amplified though, before the effects can be truly enjoyed through the relevant woofers and tweeter units.
If you already own or intend to procure a ready made amplifier, then the above units can be simply introduced in between the audio source and the amplifier input, or if you are a complete electronic freak, you may want to make the amplified section also all by you.
A stereo amplifier circuit design is shown below, one of the channels is used for driving the woofers and the other one is used for activating the tweeters.
A couple of modules discussed in the above section will need to built and connected to the shown stereo amplifier circuit for completing the proposed home theater circuit design.
Parts List
R1, R2, R3, R4, R5, R9 = 2K2,
R6, R7, R8 R10, R11, R12, R13 = 10K,
VR1, VR2, VR3, VR4 = 100K, LINEAR POTS,
C1 = 0.1uF,
C2, C3 = 0.022uF,
C4, C10, C5, C11 = 1uF, non polar,
C6, C7 = 0.033uF,
C8, C9 = 0.0033uF,
T1 = BC547B,
IC1 = 741
Comments
its working professionally thanks SWAGATAM
that's great Davis, thanks for the info
hi SWAGATAM for the second circuit(amplifier), cant a 12V transformer be used ? or it is strictly 16v transformer . if 12V transformer can be used then help me about how to make a rectifier for it to connect to the circuit like type of diodes(either IN4 OR IN5 series) to be used and capacitor rating. this is because i have failed to get a 16V transformer. thanks
Hi Davis, you can use a 12-0-12V transformer and connect it exactly as shown in the diagram….you can use 1N5408 for the diodes
sir i dont need any 7560 ic to interface with this circuit since it is very expensive
I think it won't be required as the circuit by itself is a SS processor
sir what is the maximum power that can be delivered by this system ?
will a 100 W sub woofer be able to produce its maximum efficiency with this circuit ?
Hi Rt, if the external amplifier is rated accordingly, then definitely that will be possible.
Sir i liked this circuit very much… But i am thinking of making a 5.1 surround sound system which composes 5 speakers capable of handling 100 jz to 15 Khz frequencies and one subwoofer to operate in low frequencies.. as it name indicates the system must be capable of routing the audio tracks to these speakers and the woofer according with the behavior of audio. it should have a logical circuitry for that can you please suggest a most efficient circuit for this which can be built on less expense please… i am waiting for your valuable reply and suggestions …
I think you can refer to the following processor circuit, although it does not have a frequency identifier circuit, it will do the basics of a true surround sound system.
https://www.homemade-circuits.com/2016/06/simple-surround-sound-decoder-circuit.html
the circuit will require an amplifier for which you can try interfacing the following design:
https://www.homemade-circuits.com/2012/08/exploring-ic-tda-7560-4-x-45w-quad.html
What is the differences between STK4141-II.stk4141-v.stk4141-AF…what is the difference II.V.AF
hi can you suggest a simple but effective circuit diagram for a 2 channel stereo to 6 channel (5.1)converter?I ask this because i got a 5.1 channel amplifier board from an electronic shop.It has 6 channels…. front(L),front(R),rear (L),rear(R),Center, and subwoofer.The problem is I have only 2channels out from my computer or from my purchased USB board.For subwoofer I guess I have to connect it to a subwoofer filter.And what to do for the rest?
Hi, you can try the following IC for making the required circuit:
https://www.homemade-circuits.com/2012/08/exploring-ic-tda-7560-4-x-45w-quad.html
Sir I have (160w)x2,(60)x2,(1w)x2,15oms,16oms,5oms,,,,,plz give me the design to build sound system
chethan, do you have an amplifier?
sir, i'm planing to build both of these circuits. i wanna know can i use this as a mono amp? using only one channel? if can, how to connect the inputs of a 3.5 output to the circuit?
yes that's OK.
Thank u sir, i wii try that. Btw the transformer is 2A. Is it enough?
කොටා, I think you might have done something wrong with the amplifier connections or the amp IC is faulty.
check the amplifier separately by feeding music from a cellphone headphone socket, once the amp functioning is confirmed then you can go ahead with the tone control integration
Sir, i made both circuits. But there is a sound like a motor runing from the speakers but no music. Also the rectifier bridge gets extreamly hot. I checked the transformer & its completely fine. Also the wiring is in order. What could be the problem? Please help me here..
yes you can do it by eliminating one of the volume controls of the second circuit, and by joining the 220n capacitor ends together and connecting it to a single pot.
Mujhe module one or module two ye kya hai. Jara samjhaie aur audio connect kaisay karu kush samjh me nhi aa raha hai
you'll need to make two circuits for the first one, and then connect the outputs of the these two circuits with the second circuit inputs marked as module1 and module2.
hi sir i really want to build this but i dont have a layout on pcb. can you help me sir?
Hi Allan, you can follow the part connection layout of the circuit and design the PCB yourself by following it exactly as given, it won't be difficult I can assure you that…
You mean adding a SUBWOOFER has nothing to do with the above tone control and stereo amplifier because subwoofer has its own filter and amplifier connection?
so i will connect the input of the low pass filter parallel to the input of the above tone control circuit just to share the music input?
sorry Sir i just really have no idea.
if you are using a low pass filter along with a subwoofer then the first circuit cannot be used, because the low pass filter will allow only the low Hz and block higher frequencies…
Sir, what is the maximum wattage ratings of the above stereo amplifier?
Do you have a SUB WOOFER Circuit/ Link that can be added to the above circuit?
Hi Marife,
feed the music to the input of the two identical low pass filters, then connect the outputs of these low pass filters with the inputs of the amplifier, the subwoofer speakers can be directly connected with the outputs of the amplifier channels.
all the ground connections should be made into a common line for the above connections.
Hi Sir, sorry what i mean is i got online was a circuit for low pass filter and a circuit also for a 100 watts sub woofer amplifier.
Sir you're saying that once i have already the above stereo amplifier, i don't need a separate 100 watt amplifier for the additional sub woofer?
how will i connect the sub woofer with the above stereo amplifier? please…
Hi Marife,
when you have bought the 100 watt amplifier why would you need the above 12 watt amplifier??
Hi Sir, i got online a sub woofer low pass filter and a 100w sub woofer amplifier,
would you please help me how to connect this two separate circuitry with the above stereo amplifier circuit pls!
i already get my new 12" woofer and 150w tweeter this morning and i'm planning to buy tomorrow a 12" sub woofer. So please Sir help me make it done. thanks
it's 12 + 12 watts for the amp.
you can probably use a simple low pass filter with this amp for getting a subwoofer effect from the design.
Hello Sir, you mean i can power up the first circuit with 16Vdc? but you said 12Vdc is the ideal input Sir?!
Can i Use an ordinary log dual pot Sir? and can i use a 200watts 8ohm woofer and a 100watts tweeter or the higher wattage the better Sir?
what about an additional output for a sub woofer Sir, it is possible here? How to connect it Sir?
Hello Marife,
I said this because 12V is the standard value and is mostly specified for operating electronic circuits, but since the IC 741 can handle upto 20V so 16V can be used for the first circuit.
Sir can i get the 12 volt power supply for the first circuit from the power supply of the second circuit by using a 7812 regulator?
Marife, yes you can take out 16V from the power supply positive and the center tap of the transformer
Sir what specs of woofer and tweeter i should use for the above circuit?
I think you can extract 16V from the amp power supply and use it for the first circuit, a 7812 may not be required.
Thank you Sir, what about the power supply of the first circuit if i duplicate the circuit, should i use two 7812 regulator for one of each or no need for regulator just one power source with higher amps?
you can use any standard woofer/tweeter set, just make sure that their wattage rating is well over the amps max wattage rating
where should i connect the positive terminal of the input voltage supply in the first diagram? should it be between C4 and R13? and what is the ideal voltage supply for the first circuit?
non polar will work better…use two 0.47uF in parallel for making one 1uF cap, or 3nos 0.33uF in parallel will also work…all these could be disc ceramic type
0.1uF is 10 times smaller than 1uF, it won't give proper results.
Is it possible to replace the non polar 1uF capacitors by the polar ones because the non polar ones are not easily available ..or is it possible to replace the non polar 1uF capacitors with the non polar .1uF disc capacitors?
connect positive to pin7, negative to pin4 of IC1, ideal voltage is 12V
where should i connect the positive terminal of the input voltage supply in the first diagram? should it be between C4 and R13? and what is the ideal voltage supply for the first circuit?
can you give me the full internal circuit on pcb with component name of sound box which on using current and input through 3.5mm jack please sir give me details on my id in pdf please please
sir you can give me the pcb layout of thus circuit with component name . and the total circuit of internal in home theater . my email id is satydeep143@gmail.com
please i really need this
Satyadeep, possibly i'll try to post it as soon as i become free from the schedule work
Hi I have stk4133ii ic. google don't have any amp circuit of this ic. 🙁
you can try replacing the IC in the following circuit, it could possibly work:
https://www.homemade-circuits.com/2012/04/make-this-powerful-200200-watts-car.html