All things control voltage.
Old 28th March 2012
  #1
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All things control voltage.

Hello. I am hopping that those of you with experience would be willing to enlighten the rest of us in regard to all things control voltage. Many of us were born after the heyday of CV and into the world of midi and all things digital. I for one understand what CV is used for, but not how it works or any other technical aspect. So here are a few questions.

1 How does CV work?

2 Why are the voltages different from one brand to another?

3 What is Gate, Trigger, pitch, etc?

4 What else can be controlled through CV?

5 Are CV jacks simply attached to a straight wire soldered to a trace on the circuit board or is there some sort of chip or conversion process in the line?

6 Can any old analog synth be tricked out with a CV jack for every function if space allows? If no, why not? If yes I hope the answer to number 5 is a yes

7 Why CV? What are the pros and cons vs midi and are there other options that never really gained in popularity?

8 When you have a synth that accepts both CV and midi is there any audible difference between the method of control that affects the character of the synth? An example would be the Oberheim Xpander. Will there be less stepping when controlled through CV?

Thank you,
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Old 28th March 2012
  #2
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3 gate and trigger are used for triggering sounds. you probably know what pitch is.

4 anything on analogue synthesizers. every analogue synth uses CV, if it has MIDI it still gets converted to CV. have you heard an LFO? that is CV controlling that filter or pitch.

7 pros it's sample accurate.

8 it's sample accurate so if it's played form a sequencer it will sound tighter.
Old 28th March 2012
  #3
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There is a ton of well written info on the Internet to answer your questions.

Try google.
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Old 28th March 2012
  #4
Old 28th March 2012
  #5
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Quote:
1 How does CV work?
voltage goes up..pitch becomes higher..voltage goes down.. pitch becomes lower...

you can exchange the word pitch with volume, timbre, attack time.. resonace amount... whatever your synth allows to be cv modulated..

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2 Why are the voltages different from one brand to another?
independent developments... midi was actually the first time the synth manufactors sit together to develop a standard every synth manufator uses.

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3 What is Gate, Trigger, pitch, etc?
RTFM

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4 What else can be controlled through CV?
everything that can be controled with an voltage...

you can for example overpatch the pots in an old faderboc and turn it into a cv > midi controler interface..

or with a relay turn your coffee machine on and off..thats not so easy with midi than with a cv signal...

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5 Are CV jacks simply attached to a straight wire soldered to a trace on the circuit board or is there some sort of chip or conversion process in the line?
its analog ..no chips.. just resistors

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6 Can any old analog synth be tricked out with a CV jack for every function if space allows? If no, why not? If yes I hope the answer to number 5 is a yes
sometimes not any function.. but depedend on the synth quiete a few..
My synths allways get a cv input for the filter wehn they dont come with one for example.. and on my 303 i ve outputs for the filter envelope and the accent envelope.. so i can run external modules more with the dynamic of the 303 sequences..

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7 Why CV? What are the pros and cons vs midi and are there other options that never really gained in popularity?
midi just came after cv.. just as digital synthezisers came after the analog ones..

The advantages of cv are free experimentation and ultrafine resolution..no stepping..smoooth and lightspeed fast... everything digital is primitiv in relation to this technical data.

the advantges of midi and digital.. polyphon keyboard data on 16 channels with 128 modulation controllers each, over One ! cable.
So a hell of an advantage.

but rather slow and stepped... and not accesible for patching really without writing software for it...

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8 When you have a synth that accepts both CV and midi is there any audible difference between the method of control that affects the character of the synth? An example would be the Oberheim Xpander. Will there be less stepping when controlled through CV?
Yes.. in most cases.
I not 100% sure on the expander because the filterchips are digitally controlled there.. but it should react at least faster than thru midi.
Old 28th March 2012
  #6
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A quick answer before I hit the sack, I'm sure more details will emerge

Quote:
Originally Posted by sctt_stone View Post
1 How does CV work?
It's a voltage (electric potential difference between two points) measured in Voltage (V), in most synthesizers from -5 V to +5 V, or 0V to +10V depending on the circuit.
That means the electrons are going this or the other way and what shows up on a measuring device is the difference between two points (not the amount of electrons travelling).
For instance, the green line represents the DIRECTION of electrons measured in Voltage (Y axis) over time (X axis). This picture is a triangle wave. It's called that because of the shape. Others are Square, Saw, and Sinus.

This voltage is not the current. Current (symbol I) is measured in Ampere (mAh in synths not that much), this is the rate of the flow of electric charge (the amount) - that's why the Amperage will kill you if you cause a short, not the voltage Say a module requires 200 mAh in current. That means the powersupply must be capable of keeping a steady push of this amount of power.
There's Direct Current (DC) and Alternating Current (AC) which was invented by Nicola Tesla b.t.w.. DC is a one direction stream of electrons. From 0 to 10V. Alternating current can then be negative, then be positive, since it travels back an forth.
Using a so called "rectifier" one can "flip" the negative half of the AC to the positive and thus it becomes DC since it doesn't go through 0 Volt and only travels one way, not back and forth. Some circuits require DC, and so a rectifier is placed in the path of the electrons coming in.


Electronic circuits have been made that can take variable voltage (be it DC or AC) and with it processes inside this circuit can be changed. Take for instance a VCA circuit. It's a voltage controlled amplifier. It amplifies (mostly through the use of transistors) as much as there's a control voltage coming in: Feed it more CV, then the audio on the input will be amplified more at the output.

Now here's the kicker:
That stream of electrons going back and forth can be manipulated. The difference can be changed slightly or radically. This is called "modulation".
Modulation can be AM - Amplitude modulation - how big the difference, the Voltage is can be changed. And it can be FM - Frequency modulation - which is how often the electrons reverse polarity; change direction.

Look at a basic Oscillator. It outputs a sinus. By changing the amount of FM there will be more Oscillations. This output can be used as CV (control voltage) to drive another circuit (like an LFO - low frequency oscillator), which makes the sound "wobble" when it's fed to a VCA. The DIFFERENCE between polarity changes faster or slower in time. (think Skrillex )
By AM (amplitude modulating) the sinus driving the VCA it can be made bigger or smaller (on the oscilloscope screen) wich means the VCA amplifies less (small sinus CV) or more (large Sinus).
Most VCA's can take AC but the parts (operation amplifier or OpAmp) require DC.

Now, the osciallator is set that it outputs a sine with a very high rate FM. And this output is connected to a speaker.. which makes it into a tone.
How much FM is put on the oscillator determines the tone. this must be quite precise, or the oscillator will sound flat.
There are two basic standards and they're how much voltage in FM is set to the Oscillator results in what frequency in air pressure (through the speaker) and for our ear/brain in what kind of pitch. Basically they divided the hearable range of notes by the amount of voltage. Low voltage FM results in a low note. Every scale needs a middle point and that is in modern western tuning the frequency of 440 Hz.
Then there's the Hz/Volt method wich is practically only used by Korg on the MS-10 MS-20 and by freaks like Pigtronix on some of their effect pedals.
Here's how it's arranged in the 1V/Octave PITCH CV system:
Note---V--------
A1 1.000
A2 2.000
A3 3.000
B3 3.167
C4 3.250
D4 3.417
E4 3.583
A4 4.000
A5 5.000

As you probably understand by now... audio is voltage too, inside an analogue synthesizer. So... that means that audio can be modulated as well. Or filtered, or flipped with a rectifier (since it's normally AC) or folded (so the FM is changed) etc. etc.
Bitcrushers chop off the top of the waveform. Since it's then more resembling a square wave, there's a more sudden difference between amplitude (than a gentle sloping sinus) and thus more overtones (it has to change suddenly). In a speaker more distortion means a more complicated waveform is generated. These overtones in the square wave inside the synth are in harmonic relation with the base frequency, and have different order. Our ears hear these orders differently and can differentiate. Clipping opamps or converters are generally percieved as nasty. Tubes and saturating transformers create other overtones yet again (2nd and 3rd order).
A low pass filter smoothes out these sudden changes, and turns the square back into a sinus. Thus the overtones are filtered out. And we only hear bass, since the overtones are higher frequency, and thus higher pitch. ViolĂ .

We hear DC too with our ear/brain. Here's an example how a variable rectifier circuit (circuit is a square of rectifiers) can do fun things with audio:


Quote:
Originally Posted by sctt_stone View Post
2 Why are the voltages different from one brand to another?
Buchla was/is one of the great pioneers of modern synthesizers, which came along with the invention of transistors. He invented and made stuff for NASA, but then lost interest in boring megalomaniacs with fascination for huge metallic fallusses (rockets) and started inventing and making synths. He came up with a 1,2 V per octave system not unlike above 1V/Oct.. So... when others joined the party and the synthesizer system invented by the aimable Bob Moog, and a little later Serge Tcherepnin, as well as the mad geniusses at EMS (and others) was recieving traction (through use by rock musicians) Buchla stuck with his 1,2V per Octave one, to ensure backwards compatibillity. Why would he change? It worked fine.
Korg came up with the Hz/Volt system because it was more linear and early oscillator designs tracked pitch much better with this system.
Now we have temperature stable oscillators and the Hz/Volt system is mostly obsolete. It can be generated with midi-cv interfaces like the Kenton so there's not really any problem.
Quote:
Originally Posted by sctt_stone View Post
3 What is Gate, Trigger, pitch, etc?
Gate is a square wave that tells a module to do something as long as the voltage is high. Instead of that it looks at the rising edge (the left side of the square on the oscilloscope), it simply needs acontinuous positive voltage. It is often used to open an envelope generator, which is a circuit to introduce a voltage curve that roughly mimics the amplitude of when a note on an acoustic instrument is struck, like a piano (more CV at the envelope output routed to the VCA means that there's more amplification of the audio signal passing through the VCA)
A trigger is a short pulse, the circuit connected reacts on a positive voltage ramp up and then starts doing something. Often a square can fool a trigger circuit, but sometimes not, it needs something with more amplitude. Muy Complicada.
Quote:
Originally Posted by sctt_stone View Post
4 What else can be controlled through CV?
everything that has a CV input. Often there's an attennuator (which is a circuit with variable resistor - a potentiometer - a pot) that allows the amplitude of the CV signal to be adjusted (you'd want a little bit of that LFO going into your filter, since you are not Skrillex ) Also one can have a so called "attenuverter" which also can introduce a negative voltage, so the electrodes (to go back to the basic idea of electrons travelling back and forth) are going one way (back) more. That sounds complicated but in practical terms it means you're just giving the module a differently formed signal... On the scope the waveform now has more amplitude downward.

That's obviously different than adding (or substracting) a fixed amount of voltage. On the scope the whole waveform, intact then just moves up or down on the Y-axis.

It's useful to have these (mundane) processes in modules in the synth (apart from all the flashy filters, waveshapers, folders and shifters) since it's these basic building blocks that give more control over the whole process. The simple modules of Doepfer are therefore often overlooked.

Oh yeah.. stuff can have a delay of course too. Then the waveform is shifted as a whole over the X-axis, just like moving audio files on a timeline in a DAW. This goes as much for audio as for CV, it's basically the same soup.

Quote:
Originally Posted by sctt_stone View Post
5 Are CV jacks simply attached to a straight wire soldered to a trace on the circuit board or is there some sort of chip or conversion process in the line?
CV Jacks are just like unbalanced jacks, they have one voltage rail and a ground. The ground is connected to the chassis (jacks) or theres a seperate ground when banana plugs are used. The electrons travel throug the cable and into the module's circuit and back again if it's AC, and the two connected modules become ONE circuit, through the patch cable. So patching means you connect different parts of the circuit together to form one big one. this can be an audio path (which then has to be connected to a mixer and then speaker) or a CV path which has a party in the module connected and then basta, off to ground.
Quote:
Originally Posted by sctt_stone View Post
6 Can any old analog synth be tricked out with a CV jack for every function if space allows? If no, why not? If yes I hope the answer to number 5 is a yes
Hmmm it depends. Basically.. yes, but some circuits are designed in such a way that they expect anotether part of the circuit next to it. They need a load, in case of power amplifiers for speakers suddenly switched to nothingness that can be troublesome. So this is best left to technicians who have done some research on that particular synth. Old Arp Axxe's are good candidates for this type mods, since they were fairly cheap and not so picky...
Quote:
Originally Posted by sctt_stone View Post
7 Why CV? What are the pros and cons vs midi and are there other options that never really gained in popularity?
midi is a machine language. CV is just voltage. In the case of CV it depends totally what kind of parts of the circuit (modules or external gear) can be connected for what the CV actually does. In the case of midi there's a little receiver and sender on each end that en/decode the serial messages (little voltage blips). This can be lots of things depening what message code is sent.

Quote:
Originally Posted by sctt_stone View Post
8 When you have a synth that accepts both CV and midi is there any audible difference between the method of control that affects the character of the synth? An example would be the Oberheim Xpander. Will there be less stepping when controlled through CV?
yes. since voltage is at the speed of light, and on molecular level (electrons moving back and forth) the effect on a connected circuit is inmediate. Changes will be handled by the circuit on the molecular level as well. There is a very fine resolution. Midi is not. It's 127 little steps but can be decoded in multiples of this (and smoothed out) into a CV. Just like digital audio in a DAC. Here's a page about midi: http://home.roadrunner.com/~jgglatt/
Quote:
Originally Posted by sctt_stone View Post
Thank you,
yerrr welcome. no one wrote this down here before, and I thought it needed to be done.
please note that it's night time, I'm off to bed, and that I can have made mistakes that need correction or further explanation?
I hope others will expand on this, and further explain 1-2--4 pol filters. Overtones and fundamentals, and what happens when something is slightly out of phase (unison).. etc. etc.
perhaps use videos of existing modules to make it palatable? the intarweb is way more suited for this than a book.
Oh yeah, read up on electrical circuits? I'll post some book titles tomorrow.
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Old 28th March 2012
  #7
Quote:
Originally Posted by sctt_stone View Post
Great post! Thank you for taking the time to answer these questions in such as detailed fashion. This was highly informative.
Dude, please - don't quote the entire post when they're as big as this. Reptil will not suddenly delete it to see if you saved it on your harddisk.

edit; you could've left your reply, just remove the quote itself
Old 28th March 2012
  #8
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Sorry, my forum etiquette sucks.
Quote:
Originally Posted by Yoozer View Post
Dude, please - don't quote the entire post when they're as big as this. Reptil will not suddenly delete it to see if you saved it on your harddisk.
Old 28th March 2012
  #9
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no worriesss, I'm glad you got something out of it
the quick answer turned out to be slightly longer LOL

books: Some basic knowledge of electronics when dealing with modular synths is very handy. It's not necessary, as the components are laid out in a schematic way, you (or I) don't have to know how an Oscillator circuit is built up. But it's nice to make some small mods, or to understand what the relationship between audio and CV (both electricity inside an analogue synth) are. Moreover, everything electronic that we work with (mixers, compressors, etc..) is built up from the same basic principles.

for patching ideas look at the sticky above.

"The Art of Electronics" Paul Horowitz is very good
The art of electronics - Paul Horowitz, Winfield Hill - Google Boeken

"Teach yourself: Electricity and Electronics" Stan Gibilisco is a nice introduction
Amazon.com: Teach Yourself Electricity and Electronics (0639785330844): Stan Gibilisco: Books
Old 28th March 2012
  #10
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CV is basically a poor man's MIDI


>_<
Old 28th March 2012
  #11
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Quote:
Originally Posted by infradead View Post
CV is basically a poor man's MIDI


>_<
More like the rich man's MIDI these days...
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Old 28th March 2012
  #12
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Quote:
Originally Posted by BTByrd View Post
More like the rich man's MIDI these days...
i agree
Old 28th March 2012
  #13
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CV has absolutely nothing to do with MIDI, in case anyone was under this impression

Bob Moog implemented CV and v/oct standard in the 60s. MIDI came along in the 80s. CV are continuous voltages, while MIDI is digital.
Old 28th March 2012
  #14
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On the subject of CV, does anyone have any MIDI->CV recommendations and if that would work well for sequencing? Or is it better to sequence directly from an analogue CV sequencer?
Old 28th March 2012
  #15
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@Reptil

Above and beyond the call of duty!! nice one!

Re midi to CV devices - Kenton. You get a lot for your money especially if you buy second hand and they really know what they are doing. Also the head honcho is a very helpful guy.
Old 28th March 2012
  #16
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Anyone wanna write about filters and list different filter types?
that would be nice!
Old 29th March 2012
  #17
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to quote from the great and only dude: "filters are like girlfriends"
.comparing them objectively is nice, but when you have one in your arms...in the heat of the moment.... all objectivity can go out the window.

that said, any modular will benefit from at least 3 filters to choose from - one state-variable or dedicated high-pass, one dedicated lowpass, and one raunchy/dirty/weird filter for variations.

there are oodles of 'extras' to consider: bandpass, notch, fixed filterbanks, VC filterbanks....and the weird topologies such as switched-capacitor(harvestman), combo VCF/VCOs in one(metasonix), quadtrature(mankato/octature) and on and on

there are also 'families' of components used with different sound tendencies:
VACTROL - obsolete yet fun. slow to react to cv as if built-in slewing. used in lowpass gates(buchla, makenoise etc) for woody, plucky timbres
TUBE - harmonically richer than transistor, generally. but also generally narrower ranges and unpredictable behavior under cv.
DIODE - varies widely; from EMS synthi to tb-303 they tend to sound squirty and squidgy. 'wet' and like to be goosed into screaming feedback.
OP-AMP - not seen much anymore; correct me if i'm wrong? i have run across a few op-amp ladder filters but damned if i can remember what they were in.
TRANSISTOR-LADDER - moog's famous recipe that everybody clones now that the patent is run out. smooth and syrupy with a tendency to go quieter as resonance is increased.

hopefully someone that designs these things can comment, too.
i may have a lot of experience but conveying this stuff in words is like describing the taste of food
just grab a few and go i say!
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Old 29th March 2012
  #18
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I've been leaving MIDI behind and gravitating toward a system entirely based on control voltage, that's also sync'ed to MIDI clock so I can use plugins - it's nice having Maschine and Maschinedrum locked in sync to the modular.

My favorite CV sources:

Modcan Quad LFO
Modcan VCDO
Modcan Touch Sequencer
4MS PEG
Synthtech E350 / Dual Morphing LFO
Make Noise Maths
Make Noise Pressure Points
Make Noise Rene
Livewire Vulcan + Mind Meld
TipTop Z8000

Other fun CV generators:

Anything + a quantizer
Doepfer or Cwejman external input module (or other envelope generator / comparator)
4MS RCD / SCM + Breakouts
Bleep Labs Thingamagoop V2
Silent Way

Fun modules to modulate:

Any filter
Waveshapers
Modcan VCDO
Modcan Dual Frequency Shifter
Synthtech E350
Harvestman Piston Honda
Livewire AFG
Old 9th April 2012
  #19
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Thread Starter
I have an addictive personality. If I get into the modular thing I will be broke forever. Like a true Gearslut I think I am going to start by installing a CV kit on my ARP odyssey myself. I would love to add a Mod wheel, wonder if that is possible? I hope I do not screw it up.
Quote:
Originally Posted by BTByrd View Post
I've been leaving MIDI behind and gravitating toward a system entirely based on control voltage, that's also sync'ed to MIDI clock so I can use plugins - it's nice having Maschine and Maschinedrum locked in sync to the modular.

My favorite CV sources:

Modcan Quad LFO
Modcan VCDO
Modcan Touch Sequencer
4MS PEG
Synthtech E350 / Dual Morphing LFO
Make Noise Maths
Make Noise Pressure Points
Make Noise Rene
Livewire Vulcan + Mind Meld
TipTop Z8000

Other fun CV generators:

Anything + a quantizer
Doepfer or Cwejman external input module (or other envelope generator / comparator)
4MS RCD / SCM + Breakouts
Bleep Labs Thingamagoop V2
Silent Way

Fun modules to modulate:

Any filter
Waveshapers
Modcan VCDO
Modcan Dual Frequency Shifter
Synthtech E350
Harvestman Piston Honda
Livewire AFG
Old 9th April 2012
  #20
ark
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Two points about CV that I didn't see mentioned so far in a quick readthrough of this thread:

1) Because control voltages take effect immediately (at least compared with MIDI), you can modulate a CV at audio frequencies. Such rapid modulation makes possible audio effects that MIDI is nowhere near fast enough to handle.

2) Some audio devices that accept CV inputs, notably Moogerfoogers, have current-limited power supplies that take effect if you use a TRS plug instead of a TS plug. Such devices let you use an analog expression pedal in place of a CV source. Read the manual for your device to see if this applies to you.
Old 9th April 2012
  #21
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I have my first modular system coming in August(so I am told). Ive been studying like crazy trying to prepare myself and learn everything from different sizes(I'm going 5U), formats, cases, power supplies, adapters, and on and f**king on it goes! So much to wrap your brain around. So to see a thread like this with the response Reptil and others here gave is fantastic. I hope this thread keeps going.
Old 9th April 2012
  #22
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Quote:
Originally Posted by Gringo Starr View Post
I have my first modular system coming in August(so I am told). Ive been studying like crazy trying to prepare myself and learn everything from different sizes(I'm going 5U), formats, cases, power supplies, adapters, and on and f**king on it goes! So much to wrap your brain around. So to see a thread like this with the response Reptil and others here gave is fantastic. I hope this thread keeps going.
the biggest thing is experiment and play around. always try running everything at audio rates. run audio through a clock divider and all of a sudden you have a sub harmonic generator.
Old 9th April 2012
  #23
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Quote:
Originally Posted by sctt_stone View Post
How does CV work?
about 60 hrs a week including nights and weekends, with occasional time off for parties in the woods.

- controlvoltage

Old 9th April 2012
  #24
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I don't have a clever retort like the one above, but v/oct is preferred for oscillator pitch and filter tracking because the modulation index remains consistent over the entire range IE an LFO producing a one volt waveform results in a one octave modulation anywhere in the pitch range. That's doesn't happen in a v/hz system - a one volt LFO waveform will result in different modulation index across the pitch range. One reason the original Taurus I pedals were v/hz was because there was no LFO or modulation of any kind, and the one octave pedal lended itself to a v/hz system.

Korg didn't invent the v/hz system, it has been around decades before them (the telecommunications and test industry had v/hz systems).

For every octave change, the frequencies double (exponential). V/hz calls for an exponential change of voltage (1V, 2V, 4V, 8V, etc) to result in a doubling of frequency (100hz, 200hz, 400hz, 800hz, etc) and is called a linear system (the scale ratio of numerator over denominator is linear). V/oct calls for a linear change of voltage (1V, 2V, 3V, 4V etc) to result in a doubling of frequency (100hz, 200hz, 400hz, 800hz, etc) and is called an exponential system (the scale ratio of numerator over denominator is exponential).

The key part of a v/oct oscillator is the exponential converter, which converts a linear voltage to an exponential current (current drives the charging operation of the capacitor that produces the oscillator waveform). Designing an exponential converter during the 1960s/70s was tricky engineering and wasn't as advanced as today's technology. It was also the primary source of tuning drift if not designed well.

A v/hz oscillator is identical to a v/oct oscillator with the omission of the linear to exponential converter. Although it is a simpler design that stays in tune better, it has a more limited range than v/oct. The power rails of circuits are usually +/-15VDC. If you drive a v/hz oscillator to 2V, 4V, 8V, then 16V you will find the circuit will not respond any higher than 15V, you cannot exceed the power rail. At the other extreme where the voltage divides by two for every descending octave, you reach a point where the voltage is in the millivolt range and if you thought tuning drifts were bad with v/oct it's even worse with millivolt v/hz. And with today's 5-3VDC low voltage designs it is not hard to reach that limit.
Old 2nd February 2013
  #25
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this is an ultra noob question...

but where do i buy patch cables? are they just mono 1/8" (or 1/4") ts cable? does stereo not work?

:(
Old 2nd February 2013
  #26
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Mono cables, stereo doesn't work. Most modular supply places sell them.
Old 2nd February 2013
  #27
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thank you! i could never really feel confident about it

what if i wanted to use cv out from a mono cable, but then used the exposed wires to control something else?

i have this little device from Bleep Labs that accepts CV input but doesn't have cv jacks, and now that i have a minibrute i'd love to experiment

would i just strip one end of a cable?

"The screw terminals can also act as CV inputs."

the three things on top (pot, photoreceptor, pot) all screw in on the back, i can post a picture if you want of that

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Old 2nd February 2013
  #28
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Reptil ,

This is why a little knowledge is a dangerous thing.

Its the amps and not the volts that will kill you?

Is the single most dangerous fallacy about electricity abounding around the internet today.

Please learn some ohms law before you start saying dangerous statements like this.

Its a misunderstanding of volts/amps and resistance that for many was incorrectly taught in school when often discussing static electricity which a we all know is very high voltage and very low current yet appears totally safe.

You cannot compare static electricity with normal high voltage electricity.

Capacitance and resistance matter hugely.

12000 volts is not an untypical voltage for static

and as you SHOULD know energy stored is 0.5 x c x v

so lets assume 100 pf and 1.5kohm , thats an energy dissipation of 72uJ

a TINY amount,

The reason why you only feel a tingle is that the energy is dissipated EXTREMELY quickly , over say a micro second , its peak Amperage is actually close to 8 amps but it lasts such a short period of time it cause no damage.

Now 'real' electricity ohms law says V/R = I voltage divided by resistance is current.

300volts / 2kohms would be 150ma thats enough to cause your heart to go into spasm.

V/R=I is a linear relationship.

As volts go up so does amperage and in humans we are not normal resistors as voltage increases passing through a human resistance drops so current increases.

It is an extremely misleading and potentially lethal to suggest otherwise.

As a moderator you really should know better than to say things like this.

lurn2electricity.

Gareth
Old 2nd February 2013
  #29
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i wish i was a normal resistor




thank you for the important information, i actually did read all of it and it was pretty cool
Old 2nd February 2013
  #30
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Thank you.

I left the rest of the inaccuracies alone , lifes to short no pun intended... no really.

However when it comes to stuff that can kill..........

G
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