Doepfer

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

 





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