matched pairs/quads (linear)

[Haible Juergen]

	>I have forgotten that if the Korg/Haible scheme is used (expo
converter
	>with reference input as linear input, thus linear for large
excursions
	>like keyboard and ecpo only for modulation) only good matching of
the
	>pair is necessary (preserving the symmetry of the cicuit), current
gain
	>and rbe are absolutely not interesting.

Hey Martin, "Korg/Haible scheme" is too much honor ! (blush)
I just admire what they invented.

More seriously: I haven't thought too much about matching in this
scheme. I see the temperature coupling as the main achievement
of the transistor pair. My guess would be that an offset voltage
would not hurt at all, as long as the offset voltage *drift* is low.
The drift is probably linked to the initial value somehow, but
I don't really know. Can you shed some light here ?

JH.