[sdiy] Ring Mod (was Re: Hadamard Transform Network)

[Paul Perry]

Thanks Matthew, I had no idea of the Weaver method.
Searching for details, I found a link showing how to implement it on a Nord 
Modular:
https://www.cim.mcgill.ca/~clark/nordmodularbook/nm_spectrum_shift.html
I have no idea how good it is, but I hope someone finds it useful.

paul pery Melbourne Australia

----- Original Message ----- 
From: <mskala at ansuz.sooke.bc.ca>
> On Fri, 19 May 2017, Paul Perry wrote:
>> Shouldn't those filters be 90 degree phase shift allpass filters?
>
> That's a different design.  The Weaver shifter uses two low-pass filters;
> the Bode shifter uses two all-pass filters with a 90-degree phase
> difference between them in the audio path, though the original Bode patent
> ( http://www.google.ca/patents/US3800088 ) also described using a
> Weaver-type configuration with low-pass filters to generate the
> through-zero quadrature carrier.