 |
|
|
|
 |
|
 |
|
|
The MA-7 synthesizer is growing in scope – the PCM portion of the FM/PCM hybrid is looking more like standard music industry samplers now. In the MA-3, PCM wave-table synthesis was introduced specially to cater for drum sounds – the synthesis was based on "one-shot" sampling, with limited parametric control. In the MA-7, we find keyboard zoning, with independent envelopes and filtering, plus a set of ROM wave-sounds covering the basics like piano and strings. This is a great enhancement to the MA synth engine, and while you will mainly be using the preset libraries provided, it is worth taking a peek under the hood so you can make those occasional special voices...
|
|
|
 |
|
|
Though expanded sampling is relatively new to the MA, sampling synthesis in general is probably not new to you, and as you might expect, the MA synth is quite standard in its architecture, following the recognizable conventions of other sampling synthesizers. There are one or two special details concerning memory usage for example, or the bit and sample rates of source waveforms, that need to be understood in order to fully benefit from the enhanced PCM voices, but otherwise, it’s familiar territory. We’ll start with an overview of the main PCM voice editing window and identify the main functions...
1. Multi Elements:
Five Elements can be set-up for any PCM voice. Elements cannot overlap – they exist side-by-side and the size of the element is defined by the "border-note", which is the highest note of any zone. By default, the first Element always starts at the lowest MIDI note. If its border note is set to anything other than 127, a new element is opened immediately to the right, and so on until a maximum of 5 elements have been opened. The last element (number 5) will automatically have 127 as it’s border note. Once zones have been defined, waves can be attached and individual element parameters can be edited. To help keep track of Element size and placement, the Elements are color coded and a corresponding color bar spans each zone on the keyboard along the lower edge of the editing window.
2. Attaching Waves
Waves intended for use as PCM voice waves must first be imported into the Library. (You will have noticed by now that the library is a useful and versatile component of MA-7 housekeeping – especially as libraries can be saved separately to projects). For any single project or library, there are 66 user slots to store PCM waves; these can be found by selecting the "Voice" tab then clicking on the Voice Wave radio button. Right-click in any available cell and the "New" option appears – here is what you need to know about adding new waves for the PCM voice library:
- - Mono files only
- - Maximum size is 16 KB (check the properties of your file on the PC)
- - Sampling rate is your choice (1.5k~48kHz)
- - Bit depth depends on "Preference Settings"
It is important to remember that the library is stored on your PC, where there is no memory restrictions - you must be aware of the limitations of a Voice Bank size that can be sent to the MA-7 hardware, or the number of large PCM voices that can be used in an MA-7 SMAF file as this depends on the memory of the MA chip. There are some waves available for PCM voices that are stored in ROM on the MA chip – you can use these freely, as they don’t occupy RAM memory. There are also some waves stored from location 66~127. These are a collection of general purpose instrument waves to be used alongside your own resources, but if you use them for PCM voicing, like your own waves, they occupy RAM space.
3. Element Selection
Depending on how many Elements have been set up, a corresponding number of Element Tabs will be displayed. All parameters shown on the element tab can be set for each of up to five elements. This is where the color coding comes in handy – make sure that the element selected for parameter adjustment corresponds to the notes you are playing for monitoring! There is no quick way to turn off an element, but it is simple enough to reduce the TL (total level) value to zero.
4. Element Editing Parameters
Depending on how many keyboard zones have been set up, a corresponding number of Element Tabs will be displayed. Clicking on an element tab brings the section to the front where all parameters are editable and are specific to the selected element. Let’s take a tour of the parameters...
Most of the parameters will be familiar from previous MA voice editors, but there are some points which are worth a special mention:
- Right-clicking on the element tab allows you to copy and paste the whole parameter set between elements. Be careful when using this as the wave is also copied. Border notes and zones remain intact.
- FS shows the frequency of the wave attached. When the wave is attached, you will see that this is actually the sampling frequency of your source wave. The MA synth creates different pitches for notes by multiplying the sampling frequency. The maximum frequency that can be obtained is 48kHz. Therefore, if for example, you attach a wave with a 24kHz sampling rate, you will only be able to play UP one octave from the original pitch. If the sampling frequency of your wave is 12kHz, then you will be able to play 2 octaves up from the original pitch. So the value of Fs and the original pitch of your attached wave are both factors in determining the potential range of your keyboard zones.
- KSO is Keyboard Level Scaling offset. Normally, keyboard level scaling reduces output level from the lowest to the highest note on the keyboard. The Keyboard Offset parameter moves the start point up the keyboard so that scaling can be used to "track" zones more effectively.
- LP is the loop start point and EP is the end point.
- Checking the Key Follow box raises the filter cutoff point according to the note number. The higher the note number the higher the cutoff point – all cutoff values in the envelope are affected.
|
|
|
 |
|
|
Sampling and wave-table synthesis is widely used throughout the music industry. Not only does it provide a ready means for creating traditional instrument sounds, but playing un-tuned, unusual or complex sounds back at different pitches makes for an interesting and serendipitous approach to voicing. Pads and very rich sounds can be easily made, and because they are "bundled up", often in only one or two waves in a voice, they are inexpensive in terms of polyphony. Smooth looping is always a challenge, but sometimes it can be effective to exaggerate looping effects and use this to advantage.
The examples that I chose here, are simply the results of enjoying and having some fun with the PCM synth engine. They cover a range of uses, from traditional Multi Elements techniques to one-shot loops, and hopefully, will give you some ideas for getting some "extra stuff" out of the MA-7 PCM synth. An MA-7 voice bank is provided so you can take a look at the parameters. The mp3 files are short improvisations on each voice, played directly from the edit buffer of the ATS-MA7-SMAF .
|
|
|
 |
|
|
|
|
2. Tinkle Pad
The wave used for this sound is made by playing another instrument on which each note plays a different harmonic in the series. This gives the “tinkly” effect, and looping is easy because we are not looking for a silent loop point.
3. GrumblePad
Made by sampling a good rich sound from a synth source, playing note an octave apart with a hint of a 5th for good measure. This sound required two Elements in order to get the frequency range over the keyboard. Looping in this case was made in my sound editor. (The file was saved as aiff, as MA imports the loop points from an aiff file.)
4. PercLoop
This is a percussion loop. Of course looping is easy in this case. By putting a slow filter envelope on the sound, holding a key down gradually mellows the timbre, which can be suddenly re-vitalized by replaying the key.
5. Standard EP
I wanted to make one standard traditional voice, and chose an EP for this example. It’s one of the easiest sounds for using a single cycle loop. (See the hints section for single cycle looping)
6. HarmosExample
This sound is along the same lines as Tinckle Pad except that in this case the source waves uses an additive synth to fade various harmonics in and out at random. The resulting wave has a lot of movement to it, but again, because it is made with the harmonic series, it is a "tuned" voice and can be played over different pitches.
|
|
|
|
 |
|
|
- Memory Size Issues – this is almost worth a paragraph in itself, but memory manage is a part of life for SMAF and Ringtone developers, so I’ll stick to a few memory hints... .
- Maximum Voice Data RAM for MA-7 is 16KByte. That’s for the sum of voices used in any one piece of content or SMAF file.
- This is also true for any Voice Bank sent . Use the "send selected..." option to reduce the size of voice data during the authoring process.
- Don’t forget that the other parameter data does take up some space – not much, but some, so leave some parameter room when using big files for PCM voices.
- Looping single cycles is most easily done by starting with the LP start point adjacent to the EP end point and bringing it down step by step. This can be done by selecting the LP box then using the arrow keys. This leaves the mouse/cursor free to play test notes on the keyboard.
- Set Element 1 wave to "---" in order to initialize all the Element
- Remember, original pitches can be played lower by any amount, but there is a limit to playing higher notes. The maximum value in the FS box is 48000.
|
|
|
|
