AW: VC delay module ideas?

[Haible Juergen]

It's easy to build a VC clock for BBD lines. Use a 4046 as
VCO, and a 4013 to get complementary clock pulses.
You might even use one of the 4046's internal PD's to
simply invert the output signal. If you want to drive long lines,
add buffer stages (4050). If you need expo tracking, build 
an expo VCO and a 4013.

Now my question.
The main reason why I want to build a tracking (i.e.
V/Octave) delay is the use as sound source (Karplus /
Strong - sp? - and "poor man's physical modelling" stuff.).
The main reason why I have not yet built a tracking delay 
is the analogue filter problem. Any analogue filter included
in the feedback loop would detune the whole thing.
Ok, put the anti-aliasing filters out of the loop, but you
still *want* to control the frequency response of the feedback.
So here you have one case where digital filters are
superior ! 
Is there a way to add a few "discreet" buckets at the end of
BBD line, and building a simple z-plane filter by weighting
these different tabs with different resistors?
I mean no doubt that it works in theory, but is there a simple
practical way to do this ? How would these discreet buckets
look like ? How many of them do I need for a reasonable
FIR filter ? Is this special BBD chip with separate outputs
any good here (I guess not) ?
Any ideas ?

JH.

PS.: Please don't tell me to buy a DSP. I already have a VL7.
         (;->)