[sdiy] Serge and multiples

[Tony Clark]

> > On the same note, I've many heard abandoning bananas because
> > they can't be
> > normalled internally which is just another aspect to convenience and
> > flexibility, don't you think?
> 
> There's nothing to stop you normalling bananas by electronic means.
> You could tie inputs to -ve supply rail thru a high value resistor, and add
> a comparator and 2 pole analogue switch.
> When no input is connected, the comparator will sense the input being pulled
> below the lowest possible 'valid' input and switch to the 'normal' input.

   Actually, you don't even need to get that complicated.  Think about 
this,  use a op-amp buffer with the positive pin tied to your banana jack 
input.  Also tie a 100K resistor to the positive pin which is now your 
normalized input.  When you plug into the jack, you effectively bypass 
the normalized input since the signal is being injected right into the 
op-amp positive input and the normalized signal is shut off by the 100K 
impedance.
   Works well, if you _really_ want a normalized banana modular, but I 
think it's counter-productive.
   Also, one other note about stacking banana plugs, you don't have to 
use branch-style patching (all from one output to individual ins).  
Instead, use chaining (output->input->next input->etc).  That way you 
never are stacking more than two plugs per jack.
   Oh, and about tying more than one output into a single input, this 
will only work if the jack input is literally tied to an op-amp summing 
node and resistors are built into the patch cords.  Otherwise you will 
probably get some strange attenuations in signal.

   Cheers,

   Tony, the banana addict

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