OB-8 calibration error

[Haible Juergen]

Hi Magnus,

	>Sorry, you will have to look on the scans! ;)

Thanks for the new scans.

http://home.swipnet.se/cfmd/synths/companies/oberheim/ECO434.jpg

Now that is interesting:
Apparently some of the most interesting features found their way into
the OB-8 as late as ECO434 / Rev. A8 !

Modulation inversion for Frequency and Pulse Width on VCO 2 is
a very powerful tool for creating lush sounds, and clearly on of these
things that make me prefer the OB-8 over the OB-Xa.
(Especially Strings sounds benefit from two PWM VCOs that
are modulated in opposite direction.)

And things that I've always taken for granted, like various portamento
shapes or the Lever working on VCF, only came with A8 as well.

My conclusion:

No wonder that there are people who don't share my enthusiasm for
the OB-8 - they might have an entirely different instrument !
(Not that I claim there can't be other reasons as well, of course.)

I'm crossposting this to AH, because I thought it might be of general
interest,
not just for synth-diy.
And thanks to Magnus for digging up ECO427
http://home.swipnet.se/cfmd/synths/companies/oberheim/ECO427.jpg
which confirms the long suspected envelope times miscalibration
of many OB-8's.

JH.