If your computer does not recognize your reface unit right away, you may require the Yamaha USB-MIDI Driver available from http://download.yamaha.com

Refer to page 41 of the reface Owner’s Manual for details about setting your preferences. If you plan on recording MIDI data to your DAW, for example, you may wish to turn LOCAL CONTROL = OFF, turn MIDI CONTROL = ON and turn the SPEAKER OUTPUT to Off. 

LOCAL CONTROL is the setting that determines whether the key presses (note-ons) and controller movements are sent to the reface tone engine directly (ON), or sent OUT via MIDI to the DAW for routing (OFF). It is typical to set Local Control OFF when working with an external sequencer.
MIDI CONTROL is the setting that turns specific parameters to CONTROL CHANGE (cc) MIDI messages. These can be documented to your sequencer track as MIDI messages. This setting turns on both transmit and reception of MIDI control messages.
SPEAKER OUTPUT is the setting that allows you to monitor the reface through settings determined in your software. When Speaker Output is OFF you must connect the main L/R outputs to your computer’s audio interface for monitoring control.

F2 _ Local Control = Off
E2 _ MIDI Control = On
D2 _ Speakers Output = Off

The settings are made by holding down the KEY indicated and powering ON the instrument. Repeat for each setting you wish to make. For example, hold D2 (lowest D) and power On to turn Speaker Output Off. Then hold down E2 and power On to turn MIDI Control On, and so on. Your settings will remain until you either Factory Set the instrument or you manually change them. So if this is how you plan on using the reface, it will power on ready for work next time you need it.

You can power On while holding C#2 to verify the condition of your setting following the guide in the Manual. In general when you power ON holding the highest key (Factory Reset) you can return all setting to Factory default conditions.

reface DX
The reface DX is the exception to the rule… Because it has a screen and internal memory, the Local Control and MIDI Control parameters can be set from the front panel by pressing [FUNCTION] repeatedly to select Function screen #2 “MIDI”. Advance to screen #3 to set the Speaker Output as desired. Using the corresponding red ‘button’ in the touch area, you can toggle the settings.

If you are going to play the reface from an external MIDI controller, use your DAW’s ability to route MIDI signal to each external device. Most DAWs will automatically channelize incoming MIDI signal so it will not be necessary to set the MIDI Transmit Channel. You will want to configure your DAW setup so that you can record MIDI data from the reface itself, (even if you are playing an external controller) – each of the front panel controls sends CC (Control Change) messages OUT via MIDI (except the main Volume and Octave Transpose). This means “playing” the front panel is possible – every move will be available to be recorded and played back. (See the Data List booklet for details).

And if you plan on using your computer setup to record audio, you will require an Audio Interface with at least two input channels to accommodate your reface (Left/Right) main audio outputs. The audio interface is responsible for routing the audio signal to the computer, and routing the audio output of the computer to your monitor speakers. In such a setup you will want to turn the reface’s speakers OFF.

The reface instruments default to OMNI MODE ON – which means they are set to RECEIVE MIDI data on any (and all) MIDI channels. If you are in a situation where you would like the reface to play on a specific MIDI RECEIVE CHANNEL, you can turn OMNI MODE to OFF with a cc message placed on the MIDI channel set to address the reface. Enter the Control Change cc124 (also referred to as a CHANNEL MODE MESSAGE) into your MIDI data to set OMNI MODE OFF. Turning OMNI MODE OFF will automatically set the reface to MIDI RECEIVE Channel 1. If you require a different channel (other than 1) you can send a Parameter Change (System Exclusive) message (see separate article on reface Advanced MIDI Functions).

On an analog synth this was decribed by four parameters, known as the A-D-S-R (attack, decay, sustain release). On the reface DX this will be described by eight parameters and instead of being separate from the Oscillator as in analog synthesizers, the DX-style FM includes an Amplifier Envelope Generator (AEG) in each Operator. What is this Operator?

An Operator is similar to an analog Oscillator in that it is the tone source, but it differs not only in how the tone is generated but in that it includes its own AEG and it can feature inputs for receiving signal from other Operators. All Operators initially generate a Sine Wave. And you can control how the Output Level of that Sine wave behaves as time goes forward. Why this is important in sound design is because this behavior is part of what our ears and brain use to identify a sound. The identification of sound goes beyond just the harmonic content of the wave (which we have been talking about thus far) but includes how the loudness shape evolves. We expect a “pluck” on the front of a guitar string, we expect a more gradual start when a violin string is “bowed” or when a piano string is hammered, or when a marimba is struck with a mallet. A Crash cymbal is struck with a wooden stick the result is entirely different from when it is hit with a felt covered mallet. All these differences would be described by the Amplitude Envelope Generator of your synthesizer. 

Staight talk: An AEG = How the sound comes in, what it does while it is in and then how it disappears! In FM synthesis, this is built-in to each Operator.

Basic Envelope Descriptions
Think of an electronic organ key being pressed. The volume of the note rises almost immediately, in fact, we are aware of no significant time passing between pressing the key and full volume. The sound remains at full volume all the time the key is held down (unless you move the Swell pedal or touch the Drawbars), and the sound disappears almost immediately upon releasing the key. This description of an “organ envelope” is the basic starting point when you initialize a VOICE on the reface DX (in fact, this is a common starting point when sound designing – you will find a similar default envelope in the Motif-series, and MOXF-series). This type of ON-OFF envelope is unique to the organ.

In the screen shot below is a generic musical instrument envelope shape.

Let’s consider a hammered, struck or plucked instrument sound. The graphic is TIME going left-to-right, LEVEL going bottom-to-top. As the key is struck the Output rises from 0 to Level 1 at a speed described by Rate 1. The Levels are numbers between 0 and 127, the Rates are also numbers between 0-127. A Level of 0 is no output; A Level of 127 is maximum output. A Rate of 0 is extremely slow; A Rate of 127 is very fast. Easy enough.

It may be helpful to think of the Rate in terms of “traveling”… it can be thought of as the higher the number the faster you are traveling (as in miles per hour in a car). This is actually very helpful because a RATE value of 60, for example, between two Levels is not a consistent amount of time, but a measurement of how fast you are traveling. Just as to travel 100 miles at 60 miles per hour, takes longer than it does to travel 50 miles at that same speed. The longer the distance between Level positions, the longer it will take to get there traveling at the same rate. RATE = Speed.

When you strike a piano key, there is an almost immediate rise in volume, (it is not quite as fast as an organ, but is fairly fast) – this is the ATTACK. There is then an immediate drop-off in level. All percussion family instruments have this “transient peak” – a momentary peak of energy caused by the violence of the attack. This drop-off is referred to as the Initial DECAY – and is described by Rate 2 traveling to position Level 2. (The organ does not have this initial decay – it remains at full volume). At this point, if the key is continued to be held down the sound can be said to be in the “SUSTAIN” portion of the envelope. On a piano or guitar this is the time the sound continues but slowly (due to the forces of air friction and gravity) the string retreats in volume but continues to sound. When you lift your finger at KeyOff (RELEASE) Rate 4 and Level 4 will describe how (or if) the sound returns to 0 output. 

Experiment with adjusting these values on a single Carrier Operator to get a feel for the values. The separate reface DX Reference Manual (PDF) does an excellent job of explaining the screen and its graphics. Please refer to pages 5 and 6. 

Operators that are Carriers are audible (can be heard) directly.
Operators that are Modulators affect the result of the connected Operator, be it another Modulator or a Carrier
Our use of the words OUTPUT LEVEL is more correct when talking about Operators than the word Volume. Volume describes the Output Level of a Carrier (only). 

You can navigate to the AEG screens by pressing [EDIT] (the button will be backlit)
Press button [5] EG LEVEL and button [6] EG RATE to view the currently applied AEG. The same graphic appears under each button, what differs is the parameter you are changing.

Each of these screens has four radio buttons in the upper right corner and a number in the upper center to indicate which of the four Operators you are currently Editing. Use buttons [1]-[4] to select the Operator 1-4, as necessary, or you can press the button [5] or [6] repeatedly to advance to the next Operator.
An Operator (number) in a square box is a Carrier, an operator in a round circle is a Modulator. 

Hint: A Carrier is an Operator that carries the main audible signal. It is the guitar string that has been plucked – you can hear that string in motion. The Modulator is the left hand applying the vibrato to that string – you don’t really hear the vibrato itself as a separate tone, you hear its affect on the output of the string (Carrier).
FM – the pitch of one oscillator modifying the pitch of another.

If you have any comments are questions about this article, please let us know in the forum.