here is a connections of QS7785.I print screen from 7785's datasheet.
if it is in parallel interface,the mcu is unwanted.very simple.I want to do a p2p building.


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hi: qsound chips r not very known chips, however, if their data sheet is looked into it will b seen that Qsound chips are the cheapest alternatives DIY way to multichannel sound without expensive DOLBY LICENSING process or the use of tons of operational amplifiers and delay assemblies.
Imagine 5 channel out from a stereo source or 5.1 channel out from a stereo source. I will b interested in going ahead with this project.
Hi Digi01

Looks like a good project for any one and quiet simple aswell.
On the picture that u have posted i can not see where u get a center input from . Because there is only a rigth & left input ?

Or u going to join the L & R input together with some resistors and what ohm`s or kohm`s ? or u going to use for the center input .

Oh yes where can i get some samples from if not can u sell me 2 of then . That`s if u got some spare i can pay by paypal .

This chip would be good for Quadraphonic sound to it would be nice to hear those Quad Lp`s again .
Qsound Chips

Qsound chips can deliver a 5 speaker out from a mono or stereo sound source there r two of them one is 7785 from a mono or stereo sound source it can deliver 5 speaker out 2 front, two rear and one center and this chips could be used independent of a MCU.
Other one is called QS5.1 this microchip could deliver a true 5.1 out from a mono/stereo source but a mcu is must to drive this microchip.
As for samples they r very difficult to get however may b i ll b able to arrange a few.
Scooby and jarhu:
Hi : if u want to get them urself u have to fing their distributors i mean of qsound. these chips r very small 9mm probably, I ve got 4 of them with me so meaning i dont need more than two, i could trade 1 with both of u.
QS7785 is a mono/stereo input to 5 channel out 2 front, 2 rear and 1 center and can be made without a MCU, however theres a better one called QS5.1, as the name suggests from a mono/stereo input source it produces 5.1 out 2 front, 2 rear, 1 center and 1 sub, but in this case a MCU is a must/
Hi digi01

Why waste it on a pc when it could be used on dvdplayer for home cinema with 3 lm4870 chips and use all the outputs on the QS7785 chip.:D

Or for use Quadraphonic sound on thoses quad LPs. It beats using time delays for each cannel especially since its all in one chip.:smash:

The only problem is how to mount the IC to a pcb . My soldering skills are very good but the legs on this chip or only 0.17 . Even for me this will be a very had job to do .
Is their any kind of pcb with a scoket on it that will fit this chip by bending the legs over on the chip. so it looks like the old Intel 286 or 386 processer chip.:cannotbe:

Anyway speaking of sound cards like (Creative sound blaster live 5.1) do they us a stereo input to get a 5.1 output ? Or does the software do all that stuff.:xeye: :D
SOmeone posted how a link to how to solder surface mount parts some time in the week....

Looked pretty easy, first put a tiny bit of solder on the PCB on the solder places, staick your ic on with your finger, then drop a large drop of solder over all the pins on one side, (so all the pins short).
heat the solder, and suck it out with a solder pump, the sucktion will remove all the solder, except for the bits being held by capilary action between the pins and the PCB, leaving one side soldered on.... repeat on other side/s...

Hope you work a toslink connector in somewhere
to zang thanks for the links, but i already have that file several years ago.
but i'm still curious about surround frequency respone and rear separation of this ic, because it's claim can resynthesis from downmix source e.g encoded material or it's just make an artificial sound.

but what the hell! i think this is a good project to go on.