User library FM12 Questions and Answers.

Studiowaves

Before using FM12 turn the volume down as some patches might be loud.

I realize FM sound programming is a real groove busters but only good things come out of a little work. Let me know if you have any questions. Most of the info should be there but I may have missed something or the info is not clear. However to get started there are two thing you should become familiar with.

On the top right, set the cal to the cpu usage with no notes playing or simply turn off the Cpu button which reduces Cpu when a lot of notes are playing.

The second thing is in View B and is used to customize your Keyboard Velocity Curves to get the dynamics set properly. Play your keyboard soft to hard and adjust the curves to get the proper dynamics for that keyboard. There are 3 adjustable curves to work with, select one with the orange light and all adjustment are in a row. They are velocity gain, velocity offset, followed by two choices of curves; the log curve and the hyperbolic curve. I have a lite action keyboard and a weighted action keyboard. I use a different curve for each one. Recommend adjusting it with the basic Electric Piano patch.

Once these two things are taken care of, you are good to go. I'll check back periodically and try to answer any other questions but do this first before trying other snapshots.

One final note, 2 of the 3 demo's use FM12 to generate the "Sympathetic Resonance" of a sampled piano when the sustain pedal is depressed. Have fun!

Studiowaves

Turn on the yellow button on the top to activate the display. This is the wave view of all 6 operators.

Studiowaves

Choose the ENV to see the envelope, This is operator 1. The speed is the sweep speed of the scope. The envelope continues to show but wraps to the left as it finishes the right. This is used for mode 2 of the envelope generators. Mode 1 is the factory mode. Mode 2 is has another stage. A D D H S Time and release.

Operator one is set to mode 1 and operator two is set to mode two with the orange switch in the middle. The graph is correct for operator 1 but not op2. You can use the display to view mode 2 shown above or mode 1 but mode 1 is a copy of the graph. Mode 2 has no sustain level and continues to fade out like a real instrument.

The operator can be turned off with the orange button on the right. Note that this is the amplitude section to the left of the display, not the pitch section.

Studiowaves

This is the pitch section. Each operator has its own envelope generator for pitch. The vertical slide raises the pitch above the center and lower the pitch below the center. This detune each operator to create a vibrato effect with an envelope. The orange button is an on or off button, The stacked switch is used to reduce CPU by sharing envelope generators but the detune is still individual. The LH button is for low are high strength pitch bends. You read about the retrigger in the info. On the top right is the mute button for the output.

Studiowaves

The OPERATOR is the heart and soul of the entire instrument. This is the block diagram of the arrangement.

Each harmonic can be crossfaded directly to the output. Typically the first operator is fed to the output along with some of the second harmonic. The second harmonic can also frequency modulate the first harmonic. As shown it goes to a drive or control first. Then it becomes amplitude modulated by the envelope generator before being filtered by the LPR and then it modulates the first harmonic. Each harmonic is a pure sinewave oscillator that has its own chosen frequency.

The first harmonic is frequency modulated by the FM drive followed by a LPF. The FM drive is really the sum of several inputs that feeds the LPF before actually modulating the first harmonic . Note* the LPF shares the same cutoff frequency as all operators. This makes it real easy to tailor the over all brightness of the higher notes.

Every operator has its own volume control that turns down the level of the envelope generator. Also the second harmonic can be a fixed frequency. That's pretty much it and the panel controls for the crossfade, harmonic frequencies, the 2n harmonic drive and envelope volume, are included in each operator. However the LPF frequency is located in the global FM Drive controls. There is more to it than just the operator but knowing how it works is of utmost importance if you wish to do your own programming.

Studiowaves

More on the operators FM drive and Low pass filter.

These global dials are low and high strength master drives that control the amount of frequency modulation to all operators used as carriers. They directly control the gain of the operators FM drive that is followed by the LPF in each operator. As shown the low pass filter is set to 6000hz. Note that these controls do not influence the operators local internal fm drive of the 2nd harmonic. FM strength has everything to do with to overall sound. In general the strong the strength, the brighter the tone of this instrument gets. Drive A is a low driver and Drive B is a high intensity drive. These controls are simply convenience controls that can increase or decrease the overall brightness of the overall instrument. The switch chooses A or B for easy comparisons. The mod wheel can be assigned to these to adjust the tone from your keyboard. It's just a nice way to blend in like that.

Studiowaves

The Algorithm,

The bottom operators 1,2,4 and 5 can be frequency modulated by operators 3 and 6. These are known as Carriers. The top ones are know as the modulators. As shown 3 has its own feedback and modulates itself and carriers one and two. Operator 6 simply modulates four and five. Note that the modulators can not be heard independently. Only the carries send a signal to the output. Note that the 2nd harmonic discussed previously within each operator is not shown for simplicity.

Studiowaves

The Fixed Frequency.

Each operators 2nd harmonic can alternately be switched to a fixed frequency. As shown op3 and op6 are turned on. The frequency is fine tuned with the -+ controls above the switch and course tuned by positioning the mouse pointer over the E or 0 and moving the mouse. In general fixed frequencies are mostly used in the modulators. These frequencies can be very slow and in some of the patches they are used to create a slow global vibrato for each note played. Note that FM12 also has six envelope generators dedicated to the pitch of each operator. This feature is way more complex than fixed frequency modulation but it still has it's uses.

Studiowaves

The Pitch Envelope Generator.

Each operator has a fine or course frequency modulation. If the Detune is above center the envelope generator raises the pitch of the operator. If it's below the center the pitch drops. This feature can induce vibrato at the start of the note and produce more vibrato if with stronger key velocities. Then as the note dies down the pitch change will also die down as the note fades away. This simulates the response of many stringed instruments and even drums tunings. It's essential when blending with a sampled instrument to help track the natural pitch shift of a string. Note that each operator has a vertical 6 position switch. This is useful for using the same envelope generator for several operators. By doing this, the cpu usage is greatly reduced. The same technique is used for the operators themselves. As shown op1 is using its own generator.

Studiowaves

The operators

This is where the crossfades, drives, and other items are found for each operator. It also includes the envelope generator and the breakpoints for the notes played. Everything in here plays an important part of the overall instruments sound. From low notes thru high notes, everything matters. Welcome to the world of FM programming. There is detailed info embedded in the ensemble. It's not too complicated because every operator operates exactly the same. How they interact is what makes the end result. The algorithms are your choice and are the most important feature of the entire instrument. Just keep in mind that the bottom operators actually output sound to the speakers and the top ones affect how they sound.

Studiowaves

The main audio output section.

As show, the green lights indicate that operators 1,2,4 and 5 are available as audio outputs. Below the green lights are the stereo panning controls for each operator.

The Out Filter is a 12 or 24 db per octave low pass filter before the final the final stereo outputs and it set to start rolling off at 5150hz on this patch at 12db since the 12/24 switch is not lit.

The Span is used to send the low notes more to the left and the high notes to the right. The two numbers below set the strength of the span and the offset of the pan. As shown the pan is set to full and the -21 determines which notes centered in the span. Please note that panning interacts with spanning.

The orange switch lights on the bottom enable spanning for each operator. As shown the patch does not pan operators 1 and 4, but since the span is on, they get panned depending on which note is played.

The L-H switch determines the slope of the low frequency centering module. As shown, tones below 140hz start shifting towards the center of the speakers of headphones at the rate 24 db per octave instead of 12db since the L-H switch is on. This is nice feature because low frequencies are close to omnidirectional with speaker but not with headphones. With this feature both ears get the low frequencies with headphones and speakers share the power of the low frequency energy.

Studiowaves

The midi volume section.

Midi-DB indicates the numeric midi volume value. The Midi Vx is used to vary the range of the midi volume. If Vx is set to 1 then the midi volume does not affect the volume at all. If set to 0 then it reduces FM12 in volume down to 0. It can help balance FM12 with a sampler to some degree but think of it as the amount of db reduction the midi volume does. If set to .5 then the FM12 only turns down half as much. There seems to be no golden rule on midi volume for every synth. Some aren't even linear and use half the midi volume for the top 20 db and exponentially drop the volume below half way. This make it tough to maintain a balance between FM12 when balancing it with another synthesizer as the midi volume changes. I find it best to mix FM12 with a sampler or something with the midi volume fixed around 128 then fade both together with the track volumes instead of midi volume.

Studiowaves

Sympathetic Resonance mode of operation.

This mode when turned on uses the sustain pedal to raise and lower the volume of FM12. When the sustain pedal is depressed the volume slews up at the speed set by Slewup. When the pedal is lifted the volume decreases at the rate set by Slewdown. The volume it slews down to is set at -12db on this patch. Sympathetic resonance is a something sampled pianos have struggled with in the past. With this function you can bring in artificially generate symp res with FM12. Both of the sample piano demo's use this feature.

Studiowaves

The combination module.

Each operator has a "Combi" level control that adjust the volume of this module. It produces a piano hammer sound and has a volume for that "ham" including a hammer off which saves CPU when not in use. The module also has a pink and white noise source and a crossfade P/W dial and a noise volume. The hammer is processed to have a softer hit on low strings and a harder hit on high strings. To hear the hammer it should be sent to an operator that is used as a carrier. It can be used to modulate a carrier if turned up on a modulator. Remember the carrier operator is on the bottom of the algorithms and have a green light in the output section indicating an audio output. The noise button is off in the pic which also saves CPU when not in use.

This is operator 2's Combi button. As shown with a setting of 1, whatever is being sent from the combination module is at full volume and comes out of OP2's master settings. Note that it's volume is affected by the operators output volume envelope.

Studiowaves

The Mono Mode.

Mono mode simply plays one note at a time. It features a Glide and the ability to use two other controllers for the volume and filter. Useful for wind controllers and a couple of sax patches are already set up. The slider adjusts the glide time. As shown it will glide up but it can also glide down or both up and down. The Sel Min has three modes. Normal mode has no purpose but Sel Min always plays the lowest note while select Max always plays the highest note.

Studiowaves

The feedback, transpose and volume section.

As shown in Algorithm the feedback comes out of 5 and into 6. The amount of feedback is set by the FBK slider. XPS is the transpose slider and Vol is the over volume of the patch itself. Note that the volume is not affected by the midi volume but midi volume still works. This is mainly used to blend the overall volume with a sampler. The four Keyboard selections are View A's copy of View B's switch where you set your velocity curves. This makes it easy to recall without entering view B.