Surround sound decoder

[Ziddik]

Here is a surround sound decoder circuit which i want to build so i want to knw that is this circuit perfect? is there any wrong in the schematic? Is it enough for a gud surround experience at home? Any of your lil help will be a great help for me as i am new in electronics zone. I got this schematic from sound.westhost.com

 

[Ziddik]

does U1B need the same powersupply as U1A?

 

[ericgibbs]

does U1B need the same powersupply as U1A?

Yes, the TL072 is dual OPA package.

 

[audioguru]

The horrible circuit is too simple:
1) The rear channels are exactly the same instead of being different if the music plays differently.
2) The sub-woofer plays exactly the same sounds as the center channel because it is missing a lowpass filter.
3) The left and right front speakers play exactly the same as the center speaker because there is no active levels sensing and gain manipulation.
4) It will not work if the program plays Dolby Digital Surround Sound.

 

[Ziddik]

thanx uncle $crooge. And can u pls give me a gud n simple surround sound decoder schematic?

 

[phalanx]

"Gud" and simple usually don't go hand-in-hand.

 

[audioguru]

The very old surround sound circuit you found is very simple so it has problems with old surround sound music and doesn't work with fairly new surround sound music or movies.

You cannot buy a decoder IC for the new ways of doing surround sound because it is old only to licensed manufacturers who pay a licensing fee.

 

[Ziddik]

heya uncle $crooge

i got anotha surround decoder schematic so i need your help regarding this. Does it work nd is it better than the above circuit? Thanx for the quick replay

 

[Ziddik]

and i have heard that the IC uA741 is not a good IC so will be there any mistake in the circuit after i built it? Lol sorry for too many questions.. Thank u

 

[audioguru]

You found another surround sound circuit that worked 35 years ago. Then it provided a very small amount of surround sound.
I built surround sound circuits 32 years ago with variable gain amplifiers in a Motorola IC that enhanced the surround sound from this extremely simple circuit. It was called SQ Full Logic (look in Google).
It will not decode modern Dolby Digital surround sound.

The 741 opamp is 43 or 44 years old and is not good for audio. Use a good audio opamp instead.