idea for a mixer box, looking for advice.

[johnsonsjuice]

Hello community,
This is my first post here, and i'm looking for advice.
First of al thanks to this community. I have been able to build a couple of guitar pedals using the schematics on here, they are really good!
On to my question:

I've been having this vision lately of having a mixer in wich you could stick al kinds of instruments, with a line out output. i want to be able to put guitars, basses and microphones in, so i can have a sort of DIY band mixer.
 I would use it to just bring allong to festivals, hook up to a portable speaker and just be able to jam out with people. I was thinking of having 4 inputs, with separate volume controls and 1 master volume, simple as that.

my question is how to design the electronics? is it practicle to mix all signals together into 1 amp stage, or maybe better to use a seperate amp-stage for every signal? And should i add a buffer of some sort for converting the signal to line-level? does anyone have recomendations for usefull schematics for this project? of course i would like the signal to stay as clean as possible.

thanks in advance!

[Zanius]

Hello!

I've been where you are right now and let me tell you in my personal opinion, it's better to buy a small mixing console of the shelf.
There are ways to build a mixer of course. You can go passive (just jacks and pots) but that isn't really something you would bring on stage. You can go active but you won't even get half the functions of what a commercial mixer will have.

Again, this is my personal opinion. I tried building mixing stuff but I ended up with a little 4 channel mixer off the shelf and never thought about it again.

[johnsonsjuice]

well, the thing is that i also need something to boost the signal, to be suitable for an portable speaker. So i need it to be portable. I would also like to power it with 12v or 9v, since in my application i dont have access to mains power.
I haven't found an of the shelf unit that fit these criteria:(

[Zanius]

You should clarify what you mean by "portable speaker". It's another thing boosting a signal and another thing driving a speaker.

If you are planning to drive "some" passive speaker with "some" simple diy amp and mix a bunch of instruments in there, I'm pretty sure you gonna get disappointed by the sonic result and not really be able to use it somewhere. :)

[Travis]

You’re going to carry a mixer, speaker, cables, and multiple instruments with you and hope security lets you in and other people randomly decided to bring instruments?

[johnsonsjuice]

yep, the festivals i'm going to it won't be a problem:) im allready bringing the speaker and my guitar. a mixer and mic wont be much extra

And by portable speaker i mean something like a bluetooth speaker. The same thing as you would plug your phone in to play music.

So i'm thinking just a passive mixer, followed up by a preamp. Would that work?