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Making the inverter toggle itself will result in a rocksolid 12kHz note, controlled by the systemclock. Turning the inverter into audio mode will result in 48kHz. Things like these are used in elaborate logic patchings and are beyond the scope of the G2-toolbox right now, I'm afraid. |
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Last Updated ( Wednesday, 07 June 2006 )
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Got clicks? Listen to the voice:
"Many times clicks are caused by very fast attacks of 0.5 msec, setting attacks to 7 to 10 msec helps. Very fast decays of 0.5 msec can also cause a click when the note stops, decays of 50 msec are fast enough.
Clicks can also happen when a voice is stolen by another note. Increasing polyphony helps here, the expansionboard helped me a lot on this as it doubles polyphony. I hardly run out of voices these days.
Clicks can be caused by clipping when a mix of voices hits the headroom. E.g. clicks can happen when sounds 'travel' from the voice area to the fx area and several voices are played at once. Always set the fx input module to the -6 dB setting on polyphonic patches and the output module in the fx area to +6dB to compensate the -6dB. Works many times. Clipping against the headroom is definitely an issue if filters are set to a high resonance and the GC button is Off. Keep the GC button On. Do not attempt to 'boost' signal levels in the G2 itself, outside the system headroom nothing exists. So always keep signals within the headroom. Digital systems are not like recording tape that can be driven into saturation. Boost the signal in the mixer the G2 is connected to. The reverb is very unforgiving when it gets too much input level, any single sample that clips can produce a whole reverberated cloud of clicks. There sometimes was some clicks in the delay modules in OS V1.2. Download OS V1.22 from the Clavia site and install it to solve this issue. If none of this is of any help to you, you must send in a patch that demonstrates the clipping you are talking about. As only if it doesn't happen on other people's machine you might have a hardware problem. If it does happen on other machines people might give you some advice to avoid it." That was Rob Hordijk on electro-music.com |
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Last Updated ( Wednesday, 07 June 2006 )
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Big name for a basic rule. Most modules modulation input limit is at +/-64. If you reach the limit, the modulation signal will stay at 64. Mind you, there are exceptions.
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Last Updated ( Monday, 30 January 2006 )
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Question:
Hello,
I tried to make a patch containing 2 independent alternating waves. It seems that the G2 is not able to sync the waves correctly, if they are not sinewaves. With every other wave I have a lag of exactly the wavelenght when stepping from one to the other. Have I done something wrong with the patch architecture, or is it a bug? I attached the patch and would be very happy if someone could help me with this.
Greetings,
Lukas
Answer:
The saw and square lag half a cycle. Inverting the syncing waveform will fix what you want. The reason is that the saw slopes upward and when the saw crosses zero halfway it syncs the other to the flank of that one's saw, so 180 degrees out of phase.
/Rob (drawing dismissed, couldn't reproduce correctly)Rob Hordijk on the mailing list |
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Last Updated ( Monday, 30 January 2006 )
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Why does it sound different all the time? |
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The question on the mailing list was: why does my synth always sound different after loading a patch or after the G2 recalculates. Rob Hordijk gave the answer:
The basic idea of 'virtual analog' is to not always have exactly repeating sounds, just like samples that will simply always sound exactly the same.
Instead, the idea is to get roughly the same sound, but with the slight changes from note to note that characterize acoustic instruments and analog synths. To do this in a convincing way is quite an art, an art that each of us has to learn over time.
This issue you mention has in general to do with how digital oscillators have a defined pitch but an undefined phase. Small shifts in phase between the waveforms of two or more oscillators can produce drastic changes in timbre. This is in fact one of the hallmarks of analog synths, they do never sound the same as well. Samples however will always sound the same, too much the same in general.
What one needs to keep in mind is the difference between digital and analog oscillators. Analog oscillators always drift constantly, so the phase relation between two or more oscillators is constantly changing, creating a chorus effect. Digital oscillators do not drift by themselves, so when using more than one oscillator they should always be detuned slightly by two to ten cents. This will recreate that lush and lively drifting effect of analog oscillators. But if the digital oscillators are not slightly detuned, every voice will appear to have a different timbre and after every recalculation of the patch the timbres for each voice will change. This is simply because the phase relation stays fixed during the sounding of a note if the digital oscillators are not purposely detuned.
The only way to prevent oscillators to have undefined phase shifts is to use hardsync, meaning that the output of the lowest tuned oscillator is connected to the sync input of oscillators tuned to a higher pitch. But this will also give the typical sonic effect of hardsync, and might not be what one wants.
So, the rule is to always slightly detune the second and third oscillators in a voice, or else use hardsync.
A good trick to mimic the ever and randomly driftting analog oscillators is to feed them all a slowly varying smooth random LFO signal to their pitch modulation inputs and open the modulation knob just one tick. Of course each oscillator must have its own randomly tuned random LFO waveform. This will give different sounds on each keypress and also after each recalculation of the patch. But it will be a dynamic and natural effect, immediately giving life to the sound.
An example to illustrate the above:
In addition to my previous reply a simple two oscillator patch that shows this detuning thingy. Both oscillators have a clocked Rnd module connected to their pitch inputs. These Rnd modules are clocked by the oscillators themselves, so each period of the waveform of an osc is slightly different.
If you mute the two Rnd modules the static character of the oscs can be clearly heard. But if both Rnd modules are On the sounds get very lively.
Mostly lower notes need a little deeper modulation as higher notes. This is done by applying the Keyboard morph on the pitch inputs of the oscillators.
/Rob
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Last Updated ( Monday, 30 January 2006 )
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It seems like the G2 has a limit of 60 MIDI Send Modules per slot. But you can work around that limit by placing more MIDI modules in another slot and routing them to the first one.
MIDI can send about 1000 informations per second. Having about 250 MIDI modules in all four slots (4x60) would slow down each MIDI module to 4 informations per second.
Another nice thing you can do is to make a midi-controller (by placing a bunch of controller send modules) assign those to your favourite hard/software synth and.... assign morph-groups! ALL your synths (hard or software) now can have morph-groups!
If your synth doesn't have that already (like Cameleon 5000): all your synths can now have -via MIDI - modulations in the audio range, like cross-modulation.
You've got to discriminate between MIDI that sent out physically or internally. Channels 1-16 and "This" refer to the physical MIDI output of your G2. "This" is a shortcut to the channel the slot you're in is sending/receiving. If you try to send on "this" and receive on "this" in the same patch, nothing happens because "this" refers to the channel of the external midi connection.
"Slot A-D" are internal MIDI channels. You can compare this to the other internal routings.
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Last Updated ( Monday, 30 January 2006 )
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The following is a brilliant answer by Rob Hordijk to a question somebody asked on electro-music.com's forum. Rob's G2 workshop on his own webpages has an extensive section on signals and is a must read (the whole workshop, that is). On the old NM workshop the first part of the logic workshop is on signals in the Nord Modular. Most, if not everything, applies to the G2, too. The full modulation range spans from -64 to +64. A bipolar signal happens to span this range, from -64 to +64. But as a unipolar signal spans a range of 0 to +64 it is pretty logical that the modulation depth is not the full range but only half the range. So I guess that your real question is why does the LFO output not change to a range of 0 to +128 when set to unipolar and why some modulation inputs don't accept modulation signals out of the -64/+64 range. Which actually is rather a good question. First the 'philosophical' question of why a unipolar signal has 'half the range' of a bipolar signal. It is a choice a designer of a system has to make to do it that way, and it is actually very common to do it that way. Basically it has to do with the fact that a modulation signal is always relative to some other value. E.g. a basic pitch or filter cutoff is set as a reference and then the effect modulation is applied in relation to that reference. Some things easily allow for bipolar modulations, like how a lesie type vibrato sweeps around a pitch. A leslie makes a steady pitch actually alternatingly lower and higher, a typical example of bipolar modulation. In contrast adding some vibrato to a guitar string by bending the string by a finger will only shift the pitch up, so this is a typical example of unipolar modulation. So, the basic question is does the modulation have to change some reference signal in only one direction or into two directions symmetrical around a reference signal, e.g. a pitch played by a key on the keyboard. The reference signal is modulated between two extremes, the upper limit and the lower limit. Now in practice it is very often the case that when the lower limit is actually the reference signal (so unipolar modulation) the upper limit is still the same as when it would be bipolar modulation. What you do in your patch is actually using the lowest pitch an osc can do as the reference pitch. But what you do is a 'special case'. Of course you can do it this way, but in many cases it is more practical to use e.g. the played note as the reference pitch to modulate around. In such a case you would find that if e.g. the modulation is set to a depth to sweep an octave (e.g. with a squarewave lfo to do 'octave popping') the changing from bipolar (one octave down <> one octave up) to unipolar (original pitch <> one octave up) is quite convenient, as it creates two different effects. If the unipolar setting would shift everything up, the effect would be that bipolar would be 'one octave down <> one octave up', but the unipolar 'original <> two octaves up', which would be the same as playing the bipolar modulation by a key just one octave higher on the keyboard. So in essence still be the same musical effect. When a filter is modulated it is often modulated in a unipolar way, as a bipolar modulation can suppress the overall loudness when the lower limit of bipolar modulation would push the cutoff far below the played pitch. The modulation inputs on the filters are quite sensitive, twice as sensitive as on other modules (they go from 0% to 200%). With filters it is actually quite nice that the amplitude of an unipolar lfo signal is halved, as the filter modulation input sensitivity is double. They compensate each other nicely and make sure that the modulation is positive only in reference to the cutoff of the filter. It just works out nicely that way. And now the question that touches the heart of your problem, why are there some modulation inputs that do not accept signals outside the -64/+64 range, in fact just clip the modulation at these boundaries. While there are other modulation inputs that can accept signals between -256 and +256. This has to do with how the modulation is handled internally within a module. Sometimes a modulation signal needs to be converted first, e.g. an osc is internally always linear and needs some exp/lin conversion of the pitch input signal. In some modules this is done by the calculation of a certain formula, in other modules by using a lookup tabel with values (and interpolate in the table if necessary). Tables have a fixed length and won't accept signals outside a certain modulation range that is fixed by the table length. Formulas can have intermediate calculation results that are outside a certain range, and so can set some limit to a modulation range as well. And on some modulation inputs the signals can be used straight away, so there is basically no range limit to the modulation input signal. Now the pitch modulation input can basically modulate four types of scales, the scales that are set by the scale type button next to the coarse pitch knob. In the future there might be even more types of scales implemented, e.g. a Werckmeister scale. The limit on the modulation range might have to do with this, I don't know. Anyway, it might be the case that there is the eternal dilemma that facilitating for one option might put a limit to another option. Which means that on any system there must be compromises. The common sense is not to go for super elegant solutions, but rather use the 'when it works, it works' approach. Sometimes it might turn out to be elegant and other times not. Still, when it works, it works. In the end it all depends on how much time one wants to spend on improving the elegance of an already working solution. |
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Last Updated ( Monday, 30 January 2006 )
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The G2 has one single CV input, the Pedal input. Plus one input for a gate, the Sustain input. And for CV out there are of course the MIDI CC# out modules that will work with any proper Midi->CV box.
No CV to an audio input, they are AC coupled. But, I have a lot of fun with a Doepfer Theremin module connected to the G2 Expression Pedal input. Works like a charm! I use a simple 6.3mm mono jack with sleeve to earth and tip to the analog CV. The Pedal input accepts voltages between 0 and +5 V. But a proper Pedal input is protected to negative and overvoltages, as just by accident anything can be plugged in and it should survive. 220 is of course asking too much. But the Pedal inputs of both the NM and the G2 accept LFO and CV signals from ± 15V analog systems. I don't know if this is actually in the official specs, but I used these signals and the synths survived.
The Yamaha breathcontroller cannot be used directly, as the G2 Pedal input accepts a 0V to +5V signal. So, it would only read a 0 value. Also, the BC3 needs 12V power. A little bit of electronics with a 12V adapter would be required.
Rob Hordijk on electro-music
I have made me a sequenzer in the g2 for my E 64 Sampler. This is dead evil , you can send of course note on, note offs and the note numbers as all sequenzers do but the fun starts when sending CC to controll the Emi filters and the sampling start points, i use this on orchestral samples, a lot of fun!
General Elektrick on electro-music.com |
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Last Updated ( Monday, 30 January 2006 )
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There are some magic numbers for DSP percentage and memory percentage, these numbers are 100%, 50%, 33.3%, 25%, 20%, 16.6%, 14.2%, 12.5%, etc. The reason why these numbers are so important is as these are the points where the number of voices is changed. If you have 4 maximum voices at 51% you will immediately have 8 maximum voices at 49% and so on.
Sometimes tricks are necessary, e.g. when having to use the keyboard module, which now has five outputs, one must keep in mind that it uses no dsp but almost 4% of memory. If this is only to get a velocity value it is much wiser to use a constant module and assign the velocity morph to this constant module. Then dsp is also zero but memory is only .8%, a gain of 3.1% that can just pull the patch under e.g. the 33.3% memory and give three extra voices. I think that I can safely state that the rule of thumb will be to always use the velocity morph and never use the keyboard module for only velocity. The keyboard gate is not necessary as the envelopes now have their keyboard gate signal built in. So, the keyboard module should only be used for special cases, when the note signal without the pitchbend or the pitchbend data are needed. And these are also made available by morphs, so morphs always have the priority.
Rob Hordijk on the mailing list
It's important to understand how the DSP computation loads are handled in the G2. 100% on the editor equals one DSP. Generally, and logically, computations for a discrete entity (such as a single voice from any patch, or any FX area of a slot) cannot be split up between two DSPs. So, for example, if either the memory or patch load of the VA (Voice Area) patch shows something above 50%, and the FX section too, this delivers only 3 voices (from an unexpanded G2), since every voice occupies an entire DSP, and the FX too. The rest of DSP power is wasted, so to speak. Now, if you manage to reduce the FX section loads to the point that it can reside on one DSP together with a voice (voice% and FX% <=100%), you get a fourth voice. If you manage to reduce the voice loads below 50%, zwoop, you get seven (two on each of 3 DSPs, one + FX on the last). If you run 4 slots, all with individual voice designs and FX, it can become a truly complex affair to juggle the patch loads in order to get the optimum DSP usage. It may well be that a big patch cannot deliver any more voices and you think your'e done - but if you build a simple little patch in another slot, it may well still be able to provide surprisingly many voices, as they use up the "unused niches" on the DSPs left over by the "monster patch" in the other slot. Best thing is to get an expanison. I've never seriously hit the ceiling since installing it.
tim on electro-music.com
An unexpanded G2 has got 4 (expanded 8) chips. If one voice uses 100% of one chip you have 4 (8) voices. When one voice uses 50% you have 8 voices. One voice uses 33% = 12 voices.
If the FX area uses 100% of one chip and one voice uses 100% of another one, you will have 3 voices (7). Same calculation with memory. Remember that one voice can not use more than one chip. You know how many voices you've got by looking at the Patch Load and Memory Displays, dividing 100 with the higher number and multiplying the figure before the dot with 4 (8).
If the patch load is 26 and the memory 23 you'd calculate 100/26, that's 3.84, resulting in 12 voices.
To save memory, choose modules with fewer outputs. Use morphs when possible.
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Last Updated ( Monday, 30 January 2006 )
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