[sdiy] 3300ppm or 3600ppm?

[George Hearn]

Which resistor is best to compensate for the temperature drift in the
exponential converter's typically used in VCO's or VCF's like the ASM1-VCO
R14 (http://home.swipnet.se/cfmd/synths/friends/stopp/asm1vco-1.1.pdf) or
for the SSM2040 4-pole VCF (Figure 9 on datasheet).  3300ppm/C and 3600ppm/C
seem to get used interchangeably.  Surely 1 is correct to use in these
scenarios.  I see the "Tel Labs Q81" come up in lots of schematics,  is
3600ppm/C used in these schematics because that's just what the TC of a Q81
was and is 3300ppm/C then ideal?  George