[RE: VCDO]

[mbartkow at ET.PUT.Poznan.PL]

> 
> Sorry Gene, we tried that....there's a fair am ount of audible distortion 
> caused by the PLL slewing before it locks on each note, if you set it slow 
> then it always <glides> into the note, if you set it fast then it 
> overshoots and rebounds....it don't sound good....

It glides, if you set it too slow. It overshoots, if the loop is not properly
damped. What about *right* setting which is frequency dependent ? For example,
voltage controlled loop filter. If set to track properly, the bandwidth of
the filter may increase proportionally to the target PLL frequency by applying
the same control voltage to the master VCO and the filter. Moreover, the filter
may be opened wider for the short period of frequency steepy change to allow
faster tracking. The only problem I can see here is related to phase inconsis-
tency.

regards,

--

Maciej Bartkowiak
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