Cgs synth

I can see

>that installing these resistors decreases the range. How much is it
>actually? About 50%?

Yes.

>Second observation. There is another optional 200K resistor on the B0
>node. This is not shown on the schematic either. I installed those,
>too. I wanted to get the most accurate scale. I'm not really sure if
>I've accomplished that.

Hmm. I'll have to recheck the diagram.

>Ken, can you explain the purpose of both of these optional 200K
>resistors in this R-2R ladder? Why would we want to include or omit them?

The optional resistors are the wired as an extra 7th bit, pernanently wired
to "0". Basically I do this where I wish to prevent a D/A output exceeding
the common mode range of an op-amp. Not really relevant in the Infinite
Melody circuit.

Cheers,

Ken
_______________________________________________________________________
Ken Stone sasami@...
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