Digital Volume Control

[Giuflex]

Hello, I need some help with the Digital Volume Control schematic (the one with 6 ICs). A small part where S1 & S2 are connecting is missing (left part of the image) Can anybody tell me how (and where) 2 connect those switches? Any attached images, links or other explanations are wellcome

 

[audioguru2]

Hi Giuflex,
Maybe your circuit isn't this Digital Volume Control with only one IC in our projects section:
http://www.electronics-lab.com/projects/audio/033/index.html

Please post your circuit or a link to it.

 

[Giuflex]

Here is the link 2 it

http://www.electronics-lab.com/projects/audio/010/index.html


PS: The attachment also contains the image with the schematic

 

[audioguru2]

Hi Giuflex,
I see what you mean. A wire on the left side of the schematic is missing. It connects the output of the 555 at the anode of the LED to the switches.

Are you going to make that complicated old project? Its main parts are obsolete, the CD4067 creates a fairly high distortion, especially with the capacitor to ground at its output, and the circuit has many extra un-needed parts such as a resistor for each LED when just a single common resistor is fine. The capacitor at the output of the CD4067 also reduces mid and high audio frequencies when the volume is set to near half-way. You need two of these circuits for stereo, five for surround sound.

Maxim-ic has 11 digital volume control ICs and Texas Instruments has 3. Other IC manufacurers also make them. Many are stereo, have extremely low distortion, are simple to wire and have either a built-in memory or low standby current to remember the last volume setting (like new car radios):
http://www.maxim-ic.com/AudioVideo.cfm
http://www.ti.com/audioproducts.html

 

[Giuflex]

I already have allmost all the components (I have 2 buy IC6).I'm loocking for a 'smart' schematic to control the volume 4 a long time. This one is the most complicated i've found. I have a some experience in the domain (i have this hobby since I was 6, now i'm 19 but I'm still a lamma -that's what happens when U don't have strong documentation & some adequated tools)
If those links U posted contain schematics I'll build them 2.

Thanks!

If U have any other links un can post them (I don't mind ;D ). I'm also looking for a HI-FI preamplifier schematic (with 800-1000mVolts on output),this is harder 2 find

 

[audioguru2]

I'm loocking for a 'smart' schematic to control the volume 4 a long time. This one is the most complicated i've found.

Hi Giuflex,
Sorry, but this project doesn't have a memory so it "forgets" its volume setting each time it is turned off, or the power fails. It draws a massive current so it may be impractical to provide battery backup.