What is a Drum Voice and how is it different from a Normal Voice?
A MOXF6/MOXF8 Drum Voice is an extra special Voice. If you are new to Yamaha Music Production Synthesizers, you may have never encountered a Voice architecture quite like this before. It is important to understand how this Drum Kit Voice works.
Just as there are "normal" musicians and then there are Drummers, the Drum Voice is also very special case. Typically, a Normal Voice will consist of just a single instrument, like a Piano, a Guitar or a Flute, although sometimes you might find a combination VOICE like "Piano & Strings" or a String Ensemble or Horn Section. The Drum Kit Voice is actually a combination of up to 73 individual instruments. Each KEY on the keyboard (C0~C6) is an independent instrument. You most likely have never run into a drummer with a 73-piece kit!
But that is just what you have here in the MO-XF. Each key has a different drum or percussion instrument with its own set of parameters that you can manipulate. A traditional "drum kit", in music history, is a 20th century invention first used in Jazz in the early twentieth century... called a "Trap Kit" (short for "contraption" – what someone called it when they saw how it was pieced together out of individual components). But prior to the jazz 'trap kit', drums were very much played individually and still are played individually in many instances. Think of a marching band. You have several people carrying single Bass drums, and even more carrying just a single snare. And some other who carry just a pair of cymbals... they are indeed individual instruments. And on Yamaha synthesizers the Drum Kit Voices is made up of 73 Elements.
_ An Element is a multi-sample recording. In drums, the multiple samples are stacked vertically only to a single key for velocity triggering – where in a so-called 'normal' Voice they could be laid out both across the keyboard (horizontally) and vertically.
The way Yamaha constructs the Drum Kit Voice is so that you can place any drum and/or percussion instrument waveform into a Voice – typically each sample is on a separate KEY, between C0 – C6. Each KEY can have its own group of vertically stacked samples (when we say 'vertical' this is describing a velocity swap.
_ A velocity swap will mean that as you increase the speed at which a key is struck you will switch between samples. For example, call up the Power Standard Kit 1 play the snare drum mapped to E1. As you increase the velocity you will hear it switch between five different snare drum samples; the closed high hat on F#1 will switch between four different samples.
Each KEY has its own Volume, pan position, filter, envelope, EQ, routing to the Effects, Pitch Control, etc., etc. A Drum Kit is like 73 VOICES combined in one. This allows you a great deal of flexibility when creating your music. Each KEY can be selected and edited individually. You can even assign your own favorite drums into your own USER KIT – there are 32 USER Drum Kit locations. This is useful when the snare you like is one kit and the kick you like is in another. Drum Key edits and assignments are accomplished in VOICE mode (or while you working in the Sequencer modes).
• Press [EDIT]
• Press the numbered button  to view individual KEY parameters.
You will see "VOICE – KEY" in the upper left corner of the screen. Now when you touch a key on the keyboard, its information will come to the screen. There are five tabs available: [F1]Oscillator, [F2] Pitch, [F3] Filter, [F4] Amplitude, and [F6] EQ. We should mention that sometimes a particular drum or percussion instrument is mapped to several keys – each might be a different articulation or gesture used in playing that instrument. For example, the hi-hat is typically mapped to F#1, G#1 and A#1 (Closed, Pedal, and Open) – three different articulations of the hihat cymbals. As we'll learn: Only one of these articulations can be sounded at a time.[F1] OSC (OSCILLATOR)
– On these screens you'll find the currently selected KEY, an Element ON/OFF Switch, the WAVE selection parameters (Bank, Category, Number), the Assign Mode (single/multi), Receive Note Off, Alternate Group, and the Effect routing.[SF1] WAVE:
Turning the "Element Switch" parameter to OFF will deactivate a drum KEY. One right side of the screen is where you select a Waveform by Category and Waveform Number for each KEY. There are 3,977 Waveforms.[SF2] OUTPUT:
This parameter determines if the Drum instrument is going to the kit's assigned Insert Effect, or to the MIXING's assigned SYSTEM Effects (Reverb and Chorus) or just THRU (neither). The Effect routing is per drum (KEY). A drum can be routed to the System Effects (Reverb and Chorus blocks) or it can be routed to one of two Insertion Effects selected for the kit. When a drum is routed via the Insertion Effect Output it is removed from the System Effects. When a drum is routed to an Insertion Effect it will arrive at the main drum kit output but it will have the Insertion Effect present. Any two Insertion Effects can be assigned to a Drum Kit Voice. They are treated in "parallel" or routed from "A-to-B" or "B-to-A". "Parallel" means each Insertion Effect is separated and a drum can go through one or the other. The "A-to-B" and "B-to-A" routings are what is called "in series" (one after the other).
• In the screen shot above we see a DRUM KIT Effect routing flow chart (from the MOXF6/MOXF8 Editor). The "KEY OUT" parameter in the upper left corner indicates we are looking a KEY "C1" (a Kick Drum) which is routed to INSERTION EFFECT B (blue) which is a "Classic Compressor".
• In the screen shot above we see another DRUM from the same KIT. The "KEY OUT" parameter in the upper left corner indicates we are looking the KEY "D1" (a Snare Drum) which is routed to INSERTION EFFECT A (purple) which is an "Early Reflection", then to the "Classic Compressor".[SF4] OTHER:
Any KEYS placed in the same Alternate Group
will replace the playback of any other. This is how the Closed High Hat (F#1), Pedal High Hat (G#1) and the Open High Hat (A#1) replace each other. And is how the Mute Triangle stops the Open Triangle. The "RcvNoteOff" (RECEIVE NOTE OFF) parameter is an important one to understand about drum sounds. You will notice that for most every drum sound this is set to OFF. This is what separates drum and percussion sounds from "normal" musical sounds. In a normal musical sound you hold the key down until you want the sound to stop and when you let go KEY-OFF is sent and the sound moves immediately to the RELEASE (time) parameter of the Envelope. Well with drum sounds you do not HOLD the key down to play the entire envelope of the sound. You want the entire drum to sound without having to keep your finger on the key.
In order to get a full understanding of this parameter, press the Crash Cymbal on note A2 (the "A" just below middle "C") and then do the following:
Set the RECEIVE NOTE OFF parameter ON.
It now will behave like a regular or 'normal' keyboard sound... meaning as soon as you release the key the sound will stop. This can be useful in creating a "choked" cymbal. You can quickly see why drum and percussion sounds require this parameter – you do not want to have to hold down keys in order for the instrument to complete its sound 'envelope'. The word envelope is used in synthesis to describe how something changes over time. In this case we are referring to the amplitude envelope (or loudness) – how the loudness changes over time.[F2] PITCH
– Coarse and Fine Tuning for each KEY; how the pitch of the drum responds to changes in velocity.[F3] FILTER
– Each Drum has it own filter. Basically a Low Pass Filter with programmable Cutoff, Resonance, Velocity sensitivity percentage and High Pass Cutoff parameter. Why a filter is important on synthesizers is to alter the fundamental tone (harmonic content) of a sound. In general, the more energy you put into playing (attacking) any acoustic instrument the richer it becomes in harmonics (see the article on EQUALIZATION for a discussion of harmonics). A Low Pass Filter, literally, allows the low frequencies to pass as long as they are below a particular "cutoff" point – this cutoff frequency is where the filter starts to attenuate (lessen) the loudness of certain harmonics. If you apply velocity sensitivity to a LPF, this means the harder you strike the key the more harmonics that will be allowed to pass... The faster a key goes down the higher the cutoff frequency moves – thus allowing a brighter, richer harmonic sound. This very much mimics what happens in the acoustic world: The harder you play, the richer the tone is in harmonics. This is again, programmable per drum in a drum kit.
The High Pass Filter Cutoff frequency parameter allows high frequencies to pass and therefore attenuates lows. This is useful when you wish to remove low tones from a drum sound. As you increase this parameter you will reduce low frequencies in the sound assigned to this key.[F4] AMP (AMPLITUDE)
– Each Drum has its on amplitude envelope. Here you can also find PAN, ALTERNATE and RANDOM PAN options. Amplitude is how loud a sound gets and more specifically in the case of an envelope – how the loudness changes over time. All percussive instruments are hammered or struck in some fashion. This causes what is referred to as a "transient peak". Simply put, a loud spike at the time of the attack, the sound then decays slightly and the body of the sound continues before it disappears completely. Think of a bass drum being struck by a mallet... now think of the whole process in extreme slow motion. There is the click of the mallet as it initially contacts the drumhead. There is a rapid spike in loudness, this is shortly followed by the booming response of the drum as the head starts to vibrate and is enhanced by the shell (shape) of the drum. CLICK > BOOM. The click is a peak, the boom is somewhat softer and somewhat later in time... and finally the sound disappears. That is what the ATTACK, DECAY1 and DECAY2 parameters are all about.[F6] EQ
– Each Drum has its own Equalizer. This device can be configured as a 2-band EQ, single band Parametric EQ or act as a straight level boost (+6dB, +12dB or +18dB). Being able to equalize (balance the tone and loudness) of each individual drum is extremely useful in getting the
exact sound you want from your drums. Use this equalizer when you want your KICK drum to boom or you want more snap from your snare. In other products you only have an overall equalizer (if you get that)... in the MOXF you have individual equalizers for each Element... repeat – you have
individual equalizer for each Element. There are 73 Elements in a Drum Kit VOICE; 8 Elements in each Normal VOICE.
You may wonder why a 2-band and a single parametric EQ (instead of a three band, four band, five band or a graphic EQ)... The reason is it is assigned to a single drum sound. In any percussion sound there is "the cause" (the CLICK as the mallet strikes the drum head) and "the response" (the BOOM as the drum's size creates the low thump)... 2 bands is more than sufficient for a single drum/percussion sound. A single band parametric (parametric means you can zero in on a specific frequency, boost or cut and control how wide an umbrella above and below is affected) is perfect for Element equalizing when you need to fix a specific tonal region.Building a custom Drum Kit
A Drum Kit is really 73 different Instrument sounds in one VOICE. Each drum instrument (referred to as an Element) can have its own Volume, EQ, Pan position, routing to the effects, filter, envelope, etc., etc., etc... Each drum instrument is typically triggered from a single KEY but can be one or more digital recordings (velocity switched).
• Press [EDIT]
• Press Track  to view KEY parameters
• Touch a Key to view each instrument
• Press [F1] OSCILLATOR
On this screen you can assign any Waveform to sound from this key. Obviously it make the most sense to trigger drum and percussion hits from this interface because you basically can assign one Waveform to each KEY. Remember a Waveform can consist of many individual samples - so that velocity switching is totally possible, it is simply done at the individual sample level. Each individual Sample can be assigned a KEY RANGE and a VELOCITY RANGE. When you create your own individual DRUM or PERCUSSION sound, you would assign its KEYBANK to full RANGE (C-2 through G8) if you plan on tuning that sample from the one KEY of a Drum Kit. Here's why: A Drum Kit Voice addresses the Waveform through that one KEY window. Normally you would handle tuning by striking an adjacent key (say in a piano) but to tune a single KEY in a Drum Kit that source Waveform must have a KEY RANGE to be referenced.
You will find among the Preset Wave ROM many drums that are 3-way, 4-way and even 5-way velocity switches - meaning the harder you hit the key you are able to access different sample/different articulations of that particular Drum sound. Many of the snares and hihats change as you strike the key harder. This is why you want to pay attention to your velocity when playing and recording. If all your snare drums are a 127 you will only hear that one articulation, a drummer could not, would not hit the snare drum at 127 every time, the softer hits have an entirely different timbre (and in the case of most snare drums), an entirely different sample.