Interesting description !
What I understood from the A149-1 description on Doepfer's site,
(listening with a statistician's ear) is that the upper output from
the upper section gives a Gaussian, "normal" distribution of voltages
and the lower renders the voltages with a "uniform" distribution
For the lower section, this is the other way around, with an VC
option for log-normal distribution of the lower out

btw: I was not aware of the max number of 256 realisations from the
lower section's unniform distribution (when CV D =0).
If I understand it all well, transition from uniform to normal
distribution narrows the resolution down from 256 to 2

regards
Joost




--- In Doepfer_a100@yahoogroups.com , "(i think you can figure that
out)" <petergrenader@h...> wrote:

> Hello to list. Sorry I've been away so long.
>
> Yesterday I took delivery of the new 149 Quantized/Stored
> Random Voltages and I thought I'd inflict you all with my first
> impressions..
>
> Interesting little bug indeed.
>
> As always, I am the WORST when it comes to reading manuals
> and spent about an hour with it before I downloaded Dieters
> instructions. Once I did, things that I was noticed were 'oddly
> related' made a lot more sense and I suggest to the lovers of all
> things random out there that you do the download first, because
> if you leave it to Don Buchla's typically cryptic graphics (which
> Dieter also incorporated), like me you won't really have a clue
> what is actually going on.
>
> The top half first:
>
> The top half of the 149 consists of two separate outputs of
> quantized stepped random voltages. Given that both run off the
> same random source, they track each other in a remarkable way,
> which again is modeled after the characteristics of the Buchla
> 266. The top output (n+1) is quantized in 1V increments and the
> bottom one (n squared) in 1/12 volt increments. Connected to
> the 1V/oct input of a VCO, this means that one is giving you
> octaves and the other semitones - and because both run off the
> same random source, they track one another. Connecting two
> VCOs (one to each of the two quantized outputs) will yield some
> intriguing counterpoints which every once in a while resolve
> themselves to unisons.
>
> There is a pot which controls the depth of the spread which can
> also be controlled by an external input. The level of this VC can
> be attenuated manually with its level pot.
>
> One thing to mention: the 149, at least mine, reacts to the
> TRAILING EDGE of the incoming clock. If you want your
> envelope to to track these voltage changes, you're going to have
> to invert its trigger (an 165 being the easiest solution) to get it

in

> sync with what's coming out of the 149. It took me a while to
> realize this as I thought at first the n squared out was frequency
> doubled from n+1 ( the second reacting tto both rising and failing
> edges).
>
> Outside of the usual applications, my immediate thought was
> using the N+1 out to control the 1V/oct VC input of an LFO used
> to pace a sound event, thus rendering random musical rhythmic
> intervals. Being a big fan of this type of control, I have a

pretty

> good idea where the n+1 is going to get a lot of use.
>
> The bottom half:
>
> The bottom half behaves in a less predicable manner than the
> quantized section. It's outputs relfect a true random selection of
> 256 available levels generated within the module, also in
> accordance with the conventions of the Buchla 266. So, yeah, it's
> not true random in that there are only 256 possible resolutions,
> but the net effect is pretty much the same. I guess what I'm

really

> saying is that limitation is not perceivable to me.
>
> The top output will give you a sampling from all 256 levels at any
> given time. The bottom output has an adjustable range (either a
> pot or external VC) which in effect allows you to tune the
> bandwidth of these fluctations. Although I;m not 100% positive, I
> think it's reacting like a low Q bandpass filter, the peak of which
> is the pointer of the pot. But instead of passing voltage, you're
> passing and attenuating numbers within the range of 256. . Fully
> CCW will attenuate the high numbers and give you emphasis on
> the low numbers with a gradual taper into the mid range.
> Centering the pot will emphasize the center with a graudual
> taper to both the low and high ends, and fully CW will fully
> attenuate the lower scale and give emphasis on the high
> numbers with a gradual taper into the mid.
>
> In any event, the result is very musical. Atonal, but musical if

that

> makes any sense.
>
> One thing to mention is the while this module is set up like and
> behaves much in the manner of the Buchla 266, Dieter's method
> to derive the random internally is not the same as Buchla's
> approach. Dieter opted for digital noise while Don Buchla used
> a noise-modulated triangle wave as the source, much like Serge
> and Wiard did, but their's use a saw wave. Because this
> difference (digital noise), I would be interested to hear the 149
> agianst a 266. I know of a 266 locally and wil be suggesting a
> face off in the newar future and will report back to you all,
> possibly even with audio examples.
>
> In any event - if you're lover of random voltage as I am (my
> system now has six souces for stepped random) - buy the 149,
> it's great.
>
> hope this helps,
>
> Peter
>
>
>
>
>
>
>
> I