AW: Re: Why do older Obies sound fatter?

Haible_Juergen#Tel2743 HJ2743 at
Fri Feb 16 02:33:00 CET 1996

Excerpt of my original posting:

>>Asuming the OB-X uses a quite high pitch for autotune (but here I'm only
>>guessing; please correct me!), and also assuming a certain amount
>>of omnipresent scale error, You'd have exactly what you want for
>>a fat sound after hitting autotune: Highs iin track, Lows beating.
>>On a OB-8, you have *everything* in tune, and it comes to real life
>>only a few minutes later. (I rarely hit autotune, therefore)

Your reply:

>How to turn a Xpander in tune to an OB-X in tune????
>Open the hood and blow cold air inside. That has a tremendous randomly
>effect on the pitch of the VCOs!!!

No, no, no. I am sorry if I have caused some misunderstanding, but
this was *not* what I meant. While it is *easy* to get *random* detuning
(blowing air into the synth might be one means to achieve this), I
pointed out that the autotune routine of the Ob-X must result in some
*systematic* detuning, which should have a positive effect on what
we all know as "fatness". Not totally random, but some kind of random
with a preferred direction still inherent.
If You read my original post again with this extra explanation in mind,
things might become a little clearer (sorry again).
But keep in mind, that I was only *asuming* that the OB-X tunes
in a rather high range. If it doesn't, then you can forget the whole idea;
but if it does indeed, then we might have discovered an important
factor on why the older beasts sound different, IMO.

BTW, as mentioned in a previous mail, the repeated asignment of
voices with a certain amount of detune adds to the character of
all Obie's as well. (This applies to all af them, however.)
If it were just a "random detune" - well then all the DX'es and
JD's could sound warm and fat as well (;>)

> Better, take a modrouting and put alittle
>or more amount(it depends how old the OB-X is) on the pitch of one
>oscillator. BTW, you also can choose the key where both are in tune!

Now this is the far better way, IMO! So You can *keyscale* the amount
of random detuning. Even a "normal" keyscaling can work wonders,
concentrating the beating to the lower octaves. One point for the
Xpander, Cord (;->). Btw, I used this technique on the ESQ-1 when
I owned one, but *there* I ran into limitations cause the detuning was
quite granular. (No wonder with DCO's - but I disgress)

>What did we learn??? Neil should hack the software and build in a OB-X 
>option!!!!!! Neil, did you hear this?????

Maybe it would be useful just to tune for one single note (as an option,
of course - not all the time!). But keep in mind, that you need well 
VCO's for this. The OB-X even had HFT trimmers; but You could add
*this* in software, say, only tuning the upper two octaves exactly!
With today's technology we have all degrees of freedom. Using Auto-
tune software where it is of advantage, and taking care to drop it where it
makes a sound boring.
Good idea to add it to the Jupiter! (Still don't know if You suggested
it seriously, Cord (;->) ... )

Thanks again for listening,


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