Re: The old "1U MIXER thread" Once again for fun!

[andy butler <akbutler@tiscali.co.uk>]

mark francombe wrote:
> while on some mixers the Mute goes to a Bus, that's not the
> 
>     case here.
>     Likely those switches are just single pole single throw
>     (just on/off)...it might be possible to re-purpose them
>     as sends, but I think you'd need some additional circuitry. 
> like what? 

like a resistor for each channel, and an opamp with the same value
in it's feedback loop.
...but hard to know where to take the power for the chip
without a schematic.

>  
> *Idea*
> So.. First I de-solder the switches, and hardwire the connection,,, then 
> I take a wore from the input jack to the de soldered switch, then I 
> gather all the other ends together in one almighty blob of  solder that 
> is on its way out of the mixer somehow.. (nick the headphone jack 
> maybe?) OK, heres where you think I need curcuitry? Andy? cos all the 
> outputs added together will er (struggling for technical language here) 
> take a load off each other and reduce output?, Hmm.. I just daisy chain 
> all the inputs of all my loopers together NOW; and that works fine....

....it's fine to daisy chain inputs together, but not outputs.

Outputs are low impedance, inputs are high impedance.
So, chaining outputs does what you say, chaining inputs doesn't.


You could just try using some resistors to connect 
each channel to the big blob at the output.
You'd lose some gain...but that shouldn't be a problem
sending to the EDP,as that has plenty of gain on the input.


> And theres no Behringer schematicsm is that right? 

not at the component level afaik

..and I expect the Behringer is all surface mount components,
not nice for DIY.

andy