Some build notes for the Best-tek Microbe.
These arent official notes ... just a diary to help me trouble shoot.
I'm not associated with Beast-Tek.
This ia a 8 channel drum trigger module. The official website describes it as a artificial intelligence based 8 channel algorithmic rhythmic engine with partial CV control.
There is a Rotating Clock Counter mode, a glitchy beat mode , a regular beat mode, a rotating clock divider mode and a Cellular Automation based mode. The Cellular Automation mode allows the
manipulation of organic trigger patterns from a cell grid based loosely
on Conway's Game Of Life algorithm. I bought this mainly because of the cellular-automation section.
The ATmega 328P-PU micro-controller comes pre programmed.
MCP602/MCP6022 High precision op-amp
cAREFUL .. avoid any shorts.
The build manual is excellent, with lots of great illustrations.
A easy build.
I cut some of the metal jack supports to avoid shorts.
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For more Euro DIY builds click here: http://djjondent.blogspot.com.au/2017/12/diy-index.html
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Thats a "wobbler" on the left and a "Rectangular Thing" in the centre.
Edgecutter & Tuesday
wE HAD THE PLEASURE of meeting Stijn Haring-Kuipers Principal inventor, CEO of Void B.V. and Priscilla Haring-Kuipers, Resident media psychologist.of TINRS
Terry's video synth.
A 3-trins video synthesizer, Roland V4 mixer & Edirol P10 sample player.
Have you ever wondered why Don Buchla separated control voltages from audio signals.
In virtually every other modular synthesizer system there is no division between the two.
Eurorack use 3.5mm cables.
Serge use Bananas
Moog and the rest of the 5U community use 1/4 inch jacks.
This democracy of connectors seems very practical. All voltages are treated the same and this gives increased flexibility and scope for experimenting.
"I would say that philosophically the prime difference in my (Don Buchla) approach from that of Robert Moog was that I separated sound and structure, and he didn’t. Control voltages were interchangeable with audio (in the Moog world). The advantage of that is that he required only one kind of connector and that modules could serve more than one purpose. There were several draw-backs to that kind of general approach, one of them being that a module designed to work in the structural domain at the same time as the audio domain has to make compromises. DC offset doesn’t make any difference in the sound domain but it makes a big difference in the structural domain, whereas harmonic distortion makes very little difference in the control area but it can be very significant in the audio areas. You also have a matter of just being able to discern what’s happening in a system by looking at it. If you have a very complex patch, it’s nice to be able to tell what aspect of the patch is the structural part of the music versus what is the signal path and so on. There’s a big difference in whether you deal with linear versus exponential functions at the control level..." D.B. 1964.
The last point raises questions re linear vs. audio taper, bipolar vs. unipolar, and shielded vs. unshielded cables.
Another article from SOS shines more light on the subject: "One significant difference between Buchla's approach and that of Bob
Moog was his separation of the signals used in synthesis into three
distinct classes. First, there were the audio signals, which could be
generated by oscillators, or injected into the system from devices such
as microphones or tape machines. Secondly, there were the control
voltages. Finally, there were timing pulses, which we nowadays call
clocks, gates, and triggers. By today's standards, the audio levels were
quite low (about 1V peak-to-peak) and the CVs and pulses were rather
hot, with a maximum voltage of around 15V." http://www.soundonsound.com/sos/dec05/articles/buchla200e.htm
The precise Buchla audio & CV levels fluctuated over the decades: 100 series Buchla had audio at 0dBV .... roughly 1 volt RMS.
Pulses are 15V and CVs range between 0V & +15V. Early 200 series Buchla used audio levels of +4dBV... Professional line level of +1.736 RMS
Pulses are 15V and CVs range between 0V & +15V. for early 70's 200. Late 200 Buchla dropped the CV range to 0-10V. Audio levels stayed the same at +4dBV Buchla 200e dropped audio back to 0dBV. Pulses are 10V. CVs are 0 to +10V.
Inspite of these changes over time, one thing remained constant : the huge gap between CV and audio levels. It's probably a good enough
reason for not mixing CV and audio (or at least taking extra care)
within a Buchla system .
This is making me wonder what the compatibility of the new RED Panel Buchla 100 will be like with my standard Buchla. I'd love to mix the two if that was possible. It's interesting that this separation of CV & audio is gone within that system. I guess this makes it more compatible with Eurorack.
According to the Doepfer manual, the Eurorack universe runs by these guidelines: Audio voltagesproduced
by modules such as a VCO or NOISE are typically in
the 10Vpp range (from -5 V to +5 V) Control voltages, as produced by modulation sources like a LFO and ADSR,are typically from -2.5 V to +2.5 V (5 Vpp) for
LFOs, and from 0 V to +8 V for ADSRs. These days, there are lots of companies that have +/- 5V CV ins and outs. (10Vpp) Trigger, Gate or Clock Signals, are typically rectangle shaped signals with voltage levels of 0/+5 V
These are my build notes for the Nonlinearcircuits Statues Module.
Its in eurorack format.
The name comes from the children's game Musical Statues also known as Red Light Green Light.
This is a 1 to 8 multiplexor/multiplexer….with a thru
and hold circuit attached to each output.
The active output is chosen by
whichever combination of the x00, 0x0 & 00x inputs is high.
The multiplexer IC can be either a DG408 or DG508 (DIP package)
You can
put any signal into these, crossing 1V will send it high. In the demo
video, I used the /2, /4 & /8 outputs from a Divide & Conquer
which gives it a regular 1-8 count.
Using any old signals will give a
more random effect but patterns will still emerge.
IN is the signal getting processed.
This module can be used to process CV and/or audio signals.
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A movie quote? ... Inn't he scrummy? ..
I think this is from . from Ideal ..a British dark comedy television series originally broadcast on TV channel BBC Three, ..... He is known for the line 'Inn't he scrummy?' He often talks to Moz ... He isn't particularly clever, though he is somewhat crafty.
Back to the build..........
------------------------- S1JL Power diodes are for Reverse voltage protection -Mouser Part No: 821-S1JL. Any similar rectifier with at least 1A rating should be okay, such as 1N4001, 1N4002, 1N4004. Get these sizes; SOD-123 or sub-SMA (DO-214 is a bit too big, so avoid).
Which multiplexer to use? the DG408 or DG508?....
The DG stands for Double-Gate .... its a CMOS chip..... ie there are 2 gates in the one device.
"Multigate transistors are one of the several strategies being developed by CMOS semiconductor manufacturers to create ever-smaller microprocessors and memory cells, colloquially referred to as extending Moore's law."
xOO: first bit of a 0-7 number
OxO: second bit of a 0-7 number
OOX: third bit of a 0-7 number
IN: cv/audio signal
If xOO = 1, OxO = 0 and OOx = 1, you have the binary number 101.
Converted in decimal : 5, so the output 6 is selected (you have 1 to 8
channels).
Outputs
The output selected by the x00, 0x0 and 00x inputs is fed the input
signal (thru). When the selected output is changed the signal is held at
whatever voltage it happens to be (ranges from approx -11V to 11V)
(hold)
Apologies for the poor sound on this instagram video, but it does sound really amazing.
I'll do a proper recording one of these days.
It started me wondering how many other "harmonic" related VCO modules there are out there.
Not may I think.
In Euro the The Verbos Harmonic Oscillator (HO), the Mutable instruments Plaits & Braids and the Make noise Telharmonic were some modules I could find. The HO looks related to the Buchla 148, 262v.
Do let me know if you know of any other modules that you think fall into this category.
The old Hammond organ with its drawbars is an example of this type of synthesis (additive synthesis).
In the software world Native Instruments Razor is a good example.
This brings up the topic of additive vs subtractive synthesis.
and begs the question why are there so few Synth modules that do additive synthesis?
The other euro module that I think can be loosley added to this list is the Make Noise Echophon.
The Echophon's depth control of the pitch shifter can be used to roughly approximate the harmonic series of the imputed audio .. these are the frequencies that are multiples of the fundamental. To do this the large black pitch control knob must be set to max.
Every musical sound has these harmonics.A sine wave has only the fundamental or first harmonic, a saw tooth contains all harmonics in
inverse proportion to their number. A square wave has all the odd harmonics
in the same ratio, etc etc. So with the Echophon, we can for example, just use a sine wave which has only the fundamental harmonic, and then add more harmonics by turning the depth control knob (the blue one).
Maybe this is use of pitch shifting modules to obtain spectral shifting is worth further investigation.
I understand that shifting the pitch of signal components retains their
harmonic relationships.
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Other modules worth exploring are clock dividers & multipliers .
Eurorack modules in this category include the SSSR Labs VC Divider, the 4MS Atoner, the quad clock distributor, the RCD (rotating clock divider) and SCM (shuffling clock multiplier). Use audio-rate input sources instead of LFOs with the clock dividers & multipliers to get harmonically related outputs.
The Doepfer A-137 is worth a look at.
The basic
idea of a wave multiplier is to multiply the waveform of an incoming signal
(e.g. triangle/saw/sine from a VCO) within one period of the waveform. This
leads to additional harmonics of the incoming signal. The period and
consequently the pitch of the signals remains unchanged. The A-137 works as a kind of "inverse low pass filter", i.e. it
adds a lot of harmonics to a signal that contains none or only a few harmonics
(e.g. sine or triangle waveform). In contrast to that a low pass filter (e.g. A-120)
removes harmonics from a signal that contains a lot of harmonics (e.g. saw or
rectangle waveform). ------------------------- Ladik make a Harmonic Generator in 8 HP The H-020 ------------------------
A little bit more off this topic, but still loosley related are filter bank style modules.
I think the Verbos Bark Filter, and the Frap Tools Fumana are worth investigating.
The
Bark/Fumana seem to be inspired by the Buchla 296/295/294.
Also worth a google are the 4MS Spectral Multiband Resonator (SMR) and the Serge Resonant Equalizer.
Re the Buchla 294/295/296, the Verbos Bark, the Fumana, the 4MS SMR and the Serge Res Eq. ... maybe they can be better described as "spectral processors"..... they are much much more than fixed-filter banks.
The 294 comb filter is on the extreme left.
The 295 filter
The first two, the Buchla 294 & 295, Don called comb filters, but their evolution into the amazing 296 seems plain to see.
The 296, the Fumana and the Bark are 16-band filter/spectral analyzers. Amazing tilt-like
controls, you can address odd and even bands. They also have a row of
envelope followers -- one per band.
Mark Verbos has chosen to use the "Bark scale".
It is named after Heinrich Barkhausen who proposed the first subjective measurements of loudness.
The scale ranges from 1 to 24 and corresponds to the first 24 critical bands of hearing.
The Frap Tools Fumana - Dual16 Band Spectral Editor
The outward style of each of these modules is very similar ... the upper section provides access to each filter's main output at the chosen fixed frequencies.
The Buchla 294 uses the scale:
<250/ 1K / 4K / >4K
The Buchla 295 uses the scale:
<100/ 200/ 350/ 500/ 700/ 1K/ 1.4K/ 2K/ 3.5K/ >7K
The Verbos Bark filter uses the scale :
<100/ 300/ 510/ 770/ 1.08K/ 1.48K/ 2K/ 2.7K/ 3.7K/ 5.3/ 7.7K/ >10.5K
The published Bark
band edges are given in Hertz as [0, 100, 200, 300, 400, 510, 630,
770, 920, 1080, 1270, 1480, 1720, 2000, 2320, 2700, 3150, 3700, 4400,
5300, 6400, 7700, 9500, 12000, 15500].
So the Verbos Bark uses every second Bark band. Looks like the Frap Tools has more evenly spaced
bands following something like a graphic EQ, whereas the Verbos
focuses on frequencies that are more recognised by the ears. The Fumana might be better for shaping bass sounds as it has 3 bands below 100Hz, but the Bark may be better for singling out harmonics that the human ear can distinguish ???
Quote: Fumana manual. "Each of the two filter array is based on 16 parallel analog bandpass
filters. The main filter bands from 2 to 15 are mainly based on Bessel
calculation, while bands 1 and 16 are respectively a lowpass and
highpass with a custom method to obtain better musical results. All
bands on the main filter array use an 8th order slope (48dB/oct)."