switches and logic in the g2

[settle]

could someone explain and or post a simple(simple,simple) patch showing me the most common uses of switches and logic modules in the g2? im reading the manual and having a hard time comprehending the uses. ive looked at a few patches, and tried to figue out whats going on, but to avail. im sorry for such a simple question, but i promise to explain it to the next newbie.
tanx
x

[jksuperstar]

Tough question to answer! The Logic Modules are the "basic building blocks" of all things digital (computers, stop-light controllers, etc). So the uses are endless. All of the other modules can be implemented (in theory) using only the logic modules. I don't think I can describe logic gates in terms of "here's what they are used for", because in these modular systems, they can be used for so many things. However, I don't know if your question also involves "what does a logic gate do"...so in response, you should start by looking at these links:

http://isweb.redwoods.cc.ca.us/INSTRUCT/CalderwoodD/diglogic/

Several people did many workshops on the original Nord Modular, but those techniques are directly applicable to the G2. Specifically, check out the Logic and Sample & Hold tutorials.

http://nm-archives.electro-music.com/010_NordModular/015_Workshops/

[settle]

how bout if i make my question more pointed- what are the most common uses of logic and switch modules in a modular synth. thank u for the links. i understand how logic works in theory, nots and nors. i would just like a starting point, like maybe they are used to reset sequencers? or switch between sequencers?

[oXo]

It seems that I 'm not the only one, wanting information about logic module
[settle] join me on this forum http://electro-music.com/forum/topic-3532.html

[jksuperstar] can you give us some simple example on using them ? you seem to be a modular "guru", so please, help us ?

[Rob]

[oXo]

Big Thanks Rob , for taking time to give us this huge answer !

Just to verify that I've understand, I will try to give some simple example where logic module can be used (there are mainly theorical since I don't have a Modular)
- we can use some logic module, to swap between differents FX processor regarding the amount of velocity (or note number) played.
- we can use them to invert a LFO waveform at each clock message (I don't know how it can sound )

From an IT developer point of view, we can think about it like "If .. then ..else " condition applied on "event signals".

Thanks again.

[ian-s]

Here is a simplish patch using the gate module, and an alternate version in the FX area using non logic equivalents.

The clock generates both 16th and whole beats. The keyboard gate module GATE output is combined with the 16th trigger in an AND gate. The output will be 16th’s only when a key is pressed. This output is then combined with the whole beats in an OR gate, which simply combines the continuous 1/1 and 1/16 triggers. Note that the keyboard trigger itself wont trigger the sound, it just allows the next 16th through on time.

The second version shows how the multiplier (VCA) and Mixer can do the same job as the AND and OR gate. There are differences in the way levels are treated but in this instance, they work the same. In fact, the two methods use the same MEM% but the non logic module uses slightly less DSP%. Probably because they have to drive the LED’s.

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gatesample.pch2
Description:		Download (listen)
Filename:	gatesample.pch2
Filesize:	1.38 KB
Downloaded:	1885 Time(s)

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[settle]

thanks rob for explaining things in a different way. great, i sort of understand now. but like u said im youngish, oldish (but i want it now!!).
cool tanx

[settle]

[zynthetix]

Here is a patch how logic modules can be utilized with sequencers, or in this case, counters.

Note : This patching technique is not necessarily practical, since it is very easy to use and chain sequencers in the G2. It is intended to demonstrate how multiple logic modules can be chained together to achieve a single result.



Oscillators named 1 and 3 trigger on beats 1 and 3 of the binary counter, respectively. Hit a note on the keyboard and wait a while to hear it.

If you try hooking the 1 output of the Bin counter to the trigger of an oscillator, it will trigger everytime the #1 output lights up...But what if you want the osc to trigger only on the first beat (or any particular number beat) of the binary counter's 256 beat cycle?

This is where the logic modules come in - The logic modules in the row below Osc 1 are telling the Osc 1 envelope to only trigger when 1 is ON AND 2 is OFF (2 is invertered to acheive the off) AND 4 is OFF AND 8 is OFF AND 16 is OFF, etc. (if the inverters were not involved, the osc would instead trigger when 1 is on AND 2 is on AND 4 is on, AND 8 is on etc.)

Compare this to the 8 counter. It has a seperate output/light for each number in the series of its cycle (There is just a number 3, as opposed to the Bin Counter which uses an active #1 at the same time as an active #2 in order to achieve an active #3). To trigger a note on beat 3 of the 8 counter, simply plug the 3 output of the counter into a trigger. In the binary counter, a logic AND gate would be required to specify that beat 3 occurs when output #1 AND output #2 of the bin counter are active at the same time.


To Oscillators 2 and 4, which trigger on beats 2 and 4 of the 8counter cycle respectively. They are there to demonstrate the ease of using 8counter as opposed to the BinCounter + Logic Gates, but offer far less flexibility.

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logicandcounters.pch2
Description:	Demontration of logic modules used in combination with a Bin Counter and 8 counter to contrast the differences between the two counters and use of multiple logic modules to achieve a single result.	Download (listen)
Filename:	logicandcounters.pch2
Filesize:	1.91 KB
Downloaded:	1753 Time(s)

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[mosc]

Nice explanation about that patch, Zynth.

This patch has a little surprise. It lets you know when the binary counter on the left resets. You'll have to wait a while, or crank up the clock.

[zynthetix]

the keyboard reset helps too...I guess I am too impatient for 256 pulses?

[Rob]

Here is something using logic that I personally find very useful.

The issue is that the clock generator 1/16 pulse is very short, which is actually to make the swing setting possible. The question is how to make a clock of 50% that still has the swing. Using a divider on the 1/96 output doesn't work as that output does not have the swing.

The solution (or one of the possible solutions) is to use two flipflops as a 'one and only one' circuit. This one and only one circuit is able to pass only a single clockpulse from a train of clockpulses. The clock pulse that is passed is the first full clockpulse after the one and only one circuit has received a trigger. The trigger is the 1/16 clockpulse and is fed to both the clk and the D input of the first flipflop. This will set the Q output of the first flipflop to a high level. This high level is passed on to the D input of the second flipflop. Whenever a pulse arrives on the clk of the second flipflop the output of the second flipflop will also go high and this signal must reset the first flipflop, so its output goes low. When a new pulse arrives on the clk input of the second flipflop it will clock the low that is now on the first flipflop output and the second flipflop output will go low. Now, when the the clock on the second flipflop is the 1/96 divided by three (the divider must be in the second option from its dropdown menu) the signal on the output of the second flipflop will be a clock signal that is about 50% (1/96 divided by three) and will be passed on to the output. All that needs to be done now is make sure that the clock on the second flipflop does always start on the 1/16, so the divider must be reset by output of the first flipflop to be in sync with the swing.

I admit that this seems a bit a complex way to do it, but there actually is no simpler way that works reliable. Using only a divider that is clocked by the 1/96 and reset by the 1/16 doesn't work, as the 'swinged' 1/16 comes later as the 1/96 and all will just shift by 1/96. The divider will simply never produce the right swing. So, something must be set on the 1/16 and held high for some time, which indicates a flipflop must be used. Setting this flipflop is simple, but the whole trick is how to reset this flipflop. And that is where the second flipflop and the divider come in, to create this 'one and only one' thingy (which is a well-known circuit in digital electronics).

Swing can now be set between 50% and some 66%, if there is more swing the lengthened clockpulses will start to overlap and the divider must be set to divide by two (giving a 33% pulselength) to avoid missing triggers. The final gates are to make sure there is no glitches in the clock and that the gate goes low when the clock is stopped.

Just copy and paste in your patches and don't worry too much on how it works.

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50percentClock.pch2
Description:	Example of using some logic modules to lengthen the masterclock without destroying the swing. The lengthened clock pulse is a percentage of the beat, so this works for all tempo settings (in contrast to a pulse module that needs to be adjusted for other t	Download (listen)
Filename:	50percentClock.pch2
Filesize:	2.42 KB
Downloaded:	1808 Time(s)

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[Roland Kuit]

yep like jk and Rob they are on/off switches. if you use the gate module and change stuff in this, you will see 00, 01, 10, 00 things. So It's basically some trigger functions but with nice possibilities
To make tis representable for you I made these pch's.

[Roland Kuit]

Or stuff

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OR.pch2
Description:	OR stuff	Download (listen)
Filename:	OR.pch2
Filesize:	2.22 KB
Downloaded:	1644 Time(s)

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[Roland Kuit]

XOR stuff

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XOR.pch2
Description:	XOR stuff	Download (listen)
Filename:	XOR.pch2
Filesize:	2.22 KB
Downloaded:	1676 Time(s)

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[Roland Kuit]

NAND stuff

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NAND.pch2
Description:	NAND stuff	Download (listen)
Filename:	NAND.pch2
Filesize:	2.21 KB
Downloaded:	1698 Time(s)

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[mosc]

Good examples. Logic design is a lot of fun once you spend enough time with it that you become comfortable. I used to be a professional logic designer. There are many little clever tricks that you learn from other people and you add them to your own bag-of-tricks. As I looked over other peoples' designs I noticed that people tend to have their own style of solving problems. You can see that in Nord Modular patches too.

The Nord Modulars would be much weaker without logic modules. I just wish they added a few more, like a binary up/down counter with preset inputs. Then we could make some really beautiful sequencers.

[ian-s]

Here are a couple of patches to illustrate another logic/switch group technique.

The first patch implements an idea for producing ever changing noise textures. I wondered what 8 noise oscillators would sound like mixed together with random levels, frequencies and noise widths. The patch may look complicated but it is just the same thing repeated 8 times. I added glide modules to smooth the level and noise width transitions. That was where the DSP ran out, and I still wanted to be able to scale (limit maximum value) and offset (add or subtract a constant value) the pitch and width variations!

The solution came by substituting each group of 8 RndClkA modules, with a single RndClkA, 8 “sample and holds” and an 8Counter.
Each output of the 8counter goes to consecutive S+H modules which are all connected to the same RndClkA output. Both the 8Counter and the RndClkA are sent a short burst of fast clk pulses. The S+H modules sample, then ‘hold on to’ a new unique random value. This effectively gives you an 8 output RndClkA.

This change alone saved over 20% DSP but the good news is that, instead of having to scale and offset each ouput seperatly, I can now apply the scale and offset to the RndClkA output and it will effect all 8 S+H outputs.

With the surplus DSP, I added 8 more glides for the pitch transitions, a parametric EQ, vowel filter, DelayA and a chorus. Now we have the next Alien soundtrack in a single slot.

Sorry if this post is too long winded or obscure, the patch will probably end up in a future noodle, then it becomes very difficult to explain. I know I usually cant make any sense of other peoples noodles.

[mosc]

Ian, very clever and interesting. I expected that. What I didn't expect was how this sounds - very spooky.