Rod Elliot - Audio Mixing Console (HELP!!)

[brutus89]

Hello folks,
I am new to this forum and in search of help!
I need to make a small mixer having 4 Inputs.
Each channel having a 3 Band EQ.
I'm trying to build Rod Elliot's Mixer. I read the 1st stage and its pretty clear to me.
In the 2nd stage, I have no idea what are Mixing Buses and what Subs are!!!
Can someone please help me with the basic idea of these things?
I'm able to understand the schematics but I am not able to put the bits of pieces together to understand the functioning of a mixer. Not even from Rod's Block Diagram!
I've signed up this forum just to seek help about my project.

Help is appreciated

Thanks and Regards

[audiomik]

Have a look here: Mixing console - Wikipedia, the free encyclopedia for some fairly basic information.

Mixing Buses are the signal paths for each 'sum' of the input channels and 'Subs' - otherwise Sub-Groups are similar but often are used in large mixing desks to better manage operation.
An example of using a Sub Group mix could be for a drum kit - so all of the different microphone channels used for the drum kit then appear on one stereo pair of faders.

You will also come across FX and Monitor Mix Buses.......

hope this assists and welcome to the forum
Mik

[brutus89]

Hey mik, thanks for the reply.

It still does not clear my doubt!
I am keen on building this mixer but I am not able to bring up all the circuits together in one flow.

I am talking about this project. High Quality Sound Mixer

I hope you can guide further

[audiomik]

Just think of each stage as a seperate 'function block':

You are asking about 4 inputs with 3 band EQ so each will have an:

Input preamp
EQ section
Fader
Routing


take it that you understand the first 3
Now each of these outputs, from the Faders directly for a Mono Mix or via Pan controls for a Stereo Mix or via switches or additional level pots to add further mix Buses; each goes to:

Summing Amplifier,
Fader
and then a line Output stage

which are your next stages in the signal path to the Outputs of your mixer.
With only 4 inputs don't worry about Sub Groups, but you might look at having FX send level controls to be able to separately mix channel signals to an FX unit.

Now you can also add various signal break points into individual channel and/or summed group paths called inserts for additional external control or effects such as EQ, Compressors or Echo etc

Hope this assists - getting a bit late and it's much easier to show someone this on a desk than try to explain it in writing.....

Mik