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Text File | 1991-08-22 | 22KB | 702 lines

THE SYNTHETIC SOUND EDITOR *==========================* This is the editor, which is used to design simple pieces of waveforms and to "program" the volume and pitch altering sequences. Synthetic sounds don't take much memory (that's the main advantage of them). They can use the whole 5-octave range. Although they are quite simple, they usually sound quite "cool" (and remind me of the good old C-64). Getting started ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ First load MED, select the Instr-panel, click the Synth-gadget to initialize a new synthsound. Then click the Synth-display selection gadget to display the synthsound editor. Please turn editing off. You can play the current sound with keyboard, like ordinary samples. Waveform editing ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ There are two waveform displays, the left one is the "master waveform display" and the right one is for intermediate editing (it also serves as a copy buffer). Between the waveform displays are some gadgets, that are used for transferring waveforms between displays. First there are two copy gadgets. If you press the left copy gadget, the right waveform will be copied to the left one (and vice versa). Gadget "<- EXCHANGE ->" exchanges the waveforms on the left and right. "<- MIX" mixes the left waveform to the right waveform. It is a powerful tool that can be needed quite often. "<-ADD" is similar to the mix, but it doesn't produce any average between the wforms (= waveforms, from now on). The wforms are simply added together. It's possible, that the waveforms exceed the upper and lower limits (in that case, they are truncated). Two "<- EDIT" "EDIT->" gadgets allow you to select either of the displayed wforms as a current waveform, which is then used in some editing functions. Sometimes they're automatically set (when you draw the wform with mouse, for example). "UNDO" undoes your last editing operation. It can be quite useful. "RANGE ALL" selects the current wform, so that any editing operations affect the whole wform. Freehand drawing ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ A very simple way to create wforms is to draw them from scratch. This is easily done. Just press the left mouse button and draw... There are two drawing modes. The default is "pixel". The other is "line". This can be used for drawing straight lines. There's also a mix-mode, that works in both "line" and "pixel" -mode. It mixes the drawed pixels or lines with the already existing data. Mode-selection gadgets are located below "RANGE ALL". Waveform length ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ Each waveform in synthsound can be 2 - 128 bytes long (it must be even, though). The shorter the waveform, the higher the pitch (it also depends on the wform itself). Usually, to make the pitches compatible with other instruments, you should use length 2, 4, 8, 16, 32, 64 or 128. The length can be changed with "LEN:" gadgets below the left wform, by typing in a new value or by clicking the single-step gadgets. Multiple waveforms ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ Each synthsound can consist of more than one wform (the maximum is actually 64). On the left, below the left wform, there's a set of gadgets: curr. wform # | 0 < > / 00 |/ \| next/prev number of the last waveform The arrow gadgets select the next/previous waveform. As this is a operation that is needed often, there are keyboard shortcuts: Alt-cursor left = previous Alt-cursor right = next There are two Add gadgets that allow you to increase the number of waveforms. "Last" adds a new waveform after the last wform. "Here" inserts a new wform here, and shifts the others. Del gadgets: "Last" deletes the last wform. "Here" deletes the current wform. Preset waveforms ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ There are some simple, often needed preset waveforms available at a single click. First make sure, that the destination wform is the current wform (selected with the EDIT <-/-> gadgets). Then just click the preset waveform icon. The icons are located at the bottom of the editor. The available waveforms are: sine, saw up/down, pulse, random and triangle. The CLR-gadget clears the current wform. The ALL-gadget clears the whole synthsound (so be careful..) Range operations ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ These are some basic operations, that are applied to the selected range (highlighted white). You can select the range by dragging the mouse over the wform with the right mouse button down. You can select the whole wform by clicking "RANGE ALL". The Range start/Range end gadgets at the lower right corner of the synthsound editor can be used to make small corrections to the area. When there's no range selected, there's a single horizontal white line. This is the cursor. Some editing operations need it. The cursor position can be set by clicking the right mouse button on the wform area. There are also three narrow gadgets (on the left of the preset wform gadgets) for positioning the cursor: cursor to cursor to end start | | < + > | cursor to the middle (of the wform) On the middle of the screen, there's a word "RNG", followed by a strip of gadgets: RNG Cut Copy Paste Clr Dbl Rev < > Cut (works only on left wform). It "cuts" the selected area, which is then moved to the right wform display. Copy copies the selected range to the right wform, but doesn't cut it away. Paste copies the contents of the right wform to the position pointed by the cursor. Clr clears the range. Dbl "doubles" the range, making it play one octave higher. Rev reverses the range. < or > shift the ranged data to left or right. There are two other editing operations: stretch and volume change. Stretch allows you to stretch a point of the wform towards some other point (understand?? no?? then try this:) For example, select a sine wave. Then position the cursor on the middle of the waveform (there's a gadget for this purpose, see above). Now activate the "STRETCH:"-gadget (on the left lower corner of the synthsound ed). Type in the amount of moving, e.g. 32. This should demonstrate it... If the number you type in is negative, the point is stretched to left. Volume change allows you to increase/decrease the volume of selected range: First select a range. Then activate the "VOL.CHG:"-gadget. Now you must enter the amount of volume change (in %'s). For example, to halve the volume, you should type 50. If you want to double the volume, type 200. The volume will be changed when you press Return. Transformation ¯¯¯¯¯¯¯¯¯¯¯¯¯¯ This is quite a powerful feature. It allows you to change a waveform to another smoothly (by creating the waveforms between them). Demonstration: Allocate 9 new waveforms (click Add/Last 9 times). Now you have 10 wforms. Move to wform 00, and select a pulse waveform, for example. Then click Transform: Start to mark the beginning of transformation range. Move to wform 09 (the last one). Put here a sine wform. Click Transform: Do, and the magic is done. If you view the wforms 01 - 08, you'll notice that there's now a smooth transition from the pulse wave to the sine wave. ----------------------------------------------------------------------------- THE PROGRAMMING LANGUAGE ======================== Note: please read this section carefully before experimenting, because you can lock up your machine with the synthsound programming language (as with any other language) The programming language is used for controlling the volume/pitch/vibrato/ waveforms/arpeggio/etc... of the synthsound. It consist of simple keywords, of which some have an argument. The programming is done using two lists of commands/numbers. These lists are displayed through a small window below the right waveform display. First there are line numbers in decimal and hex (two leftmost columns). The middle column contains the volume sequence, while the rightmost is the waveform/pitch sequence. volume ctrl seq | line | waveform ctrl seq | | | 00 00 40 00 01 01 END END These lists are both max. 127 ($7F) entries long. The list is always terminated with "END" instruction (it's automatically there so you don't have to do that). You can scroll the list with cursor up/down -keys. The cursor can be moved horizontally using the cursor left/right -keys. There are six possible cursor locations (3 for both lists). When entering commands, the cursor should be on the leftmost position of that list. Values are entered by pointing the cursor over the value to be changed and entering a new value. Commands and numbers are entered with keyboard. You can insert entries to the list with the Return-key (or clicking Ins-gadget), and delete using Del (or clicking Del-gadget). JMP commands are renumbered when entries are inserted or deleted. ALL NUMBERS IN THE SEQUENCE LISTS ARE HEXADECIMAL. Just remember this, and you have no problems (fingers crossed :^) Also, the editing (Esc) must be on before the lists can be changed. First, let's examine some example sequences: This is a volume sequence: 00 40 <= set initial volume to 64 (hex $40, did you already forget?) 01 CHD <= command, that means "Set volume change down speed" 02 03 <= argument (speed = 3) 03 END Here's another: 00 00 <= initial volume = 0 01 CHU <= Command: Set volume change up 02 07 <= speed = 7 03 WAI <= Command: Wait 04 10 <= wait 10 pulses 05 CHU <= Set volume change up 06 00 <= speed = 0 -> stop changing volume 07 WAI <= Wait 08 70 <= 70 pulses 09 CHD <= Cmd: Set volume change down 0A 01 <= speed = 1 (slow) 0B END Third: 00 40 <= vol = $40 01 30 <= vol = $30 (without command, the values are volume changes) 02 20 <= vol = $20 03 END And fourth, finally: 00 40 <= vol = $40 01 CHD <+ <= change down speed.. 02 01 | <= ..= 1 03 WAI | <= Wait.. 04 20 | <= ..20 05 CHU | <= change up 06 01 | <= ..1 07 WAI | <= Wait.. 08 20 | <= ..20 again 09 JMP | <= Jump (= goto) 0A 01 -+ <= to line number 01 0B END Now some wform/pitch sequences. Wform/pitch sequence is the "mastersequence" while the volume sequence is a kind of "slave sequence". First: (the simplest case) 00 00 <= set waveform #00 01 END A bit more complex: 00 VBS <= set vibrato speed 01 40 <= speed = $40 02 VBD <= set vibrato depth 03 02 <= depth = 2 04 00 <= waveform #00 05 END And very complex: 00 ARP <= start arpeggio sequence 01 00 \ 02 03 arpeggio values 0, 3, 7 (minor chord) 03 07 / 04 ARE <= end arpeggio sequence 05 VBD <= vibrato depth 06 06 <= 6 07 VBS <= vibrato speed 08 40 <= $40 09 00 <= set waveform #0 0A 01 <= set waveforms 01 - 0A (one timing pulse/waveform) 0B 02 | | 0C 03 \ / 0D 04 \_/ 0E 05 0F 06 10 07 11 08 12 09 13 0A and back to #01... 14 08 15 07 16 06 17 05 18 04 19 03 1A 02 1B 01 1C JMP <= jump 1D 09 <= to position 09 (restart waveform changing) 1E END ----------------------------------------------------------------------------- You can learn a lot by examining the example synthsounds and by experimenting. Now, some reference... About timing ¯¯¯¯¯¯¯¯¯¯¯¯ For both sequence lists, most of the commands are fetched, executed, and the next command is immediately fetched. There are also some commands that wait for the next timing pulse, this is important because the computer would otherwise send all its time executing the sequence lists (and would hang up). You should take care that all loops contain a command, that waits for the next timing pulse. These commands are WAI (Wait), vol chg (plain number in the volume list) and set waveform (plain number in pitch/wform list). For example, the following loops will hang up your computer: 00 JMP 00 CHU <-+ command CHU doesn't wait 01 00 01 02 | ... 02 JMP | 03 00 --+ While the following would not: 00 20 00 WAI 01 JMP 01 02 02 00 02 JMP 03 00 Execution speed ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ The synthsound handling routine is called once every interrupt. This means that the handling is usually done 6 times/note (can be changed with secondary tempo, see main docs). Both lists have an execution speed, that is the speed of the operation. When the speed is 1, the next command is fetched/pitch changed etc. on every interrupt. If the speed was 2, it would happen every second interrupt (runs two times slower). The initial execution speed can be set with the two speed gadgets. During executing, the speed can be changed with command SPD. VOLUME SEQUENCE LIST COMMANDS ============================= 1. Set volume Command: --- Keyboard: --- (key needed to enter the command) This is the default command (no command identifier). It sets the absolute volume of the synthsound. It should be 00 - 40. Note that the relative track volumes are not used in synthsounds (mostly because of performance reasons). Example: 00 30 ;volume = $30 01 10 ;volume = $10 ... 2. End sequence Command: END Keyboard: --- This command terminates the volume sequence list. It's always there and automatically inserted. You can't insert commands past this one. 3. Set volume change down speed Command: CHD Keyboard: D This command sets the speed, in which volume is decreased each timing pulse. The volume starts changing automatically after this command. To stop automatic volume sliding, issue this command with speed 00. Example: 00 CHD 01 05 ;speed = 5 ... 10 CHD 11 00 ;speed = 0 -> stop sliding 4. Set volume change up speed Command: CHU Keyboard: U This command is like CHD, except it sets the volume change up. 5. Wait Command: WAI Keyboard: W This command waits for specified amount of timing pulses (pause). Example: 03 WAI 04 10 ;wait for 16 ($10) pulses to occur 6. Jump Command: JMP Keyboard: J Causes an immediate jump to another position of the volume list. Example: 05 JMP 06 0A ;jump forward to line 0A 7. Jump waveform sequence Command: JWS Keyboard: Shift-J This command causes a jump in the waveform sequence. This can be used for example, to trigger a pitch change at the end of the vol seq list. Note that this DOESN'T cause a jump TO waveform sequence. Example: 04 JWS 05 0F ;Cause jump in waveform sequence list 8. Halt Command: HLT Keyboard: H This has the same effect with command END (halt execution), but it can be inserted in the middle of the sequence list. Example: 03 HLT 04 04 ;some other code (can be accessed with JMP instruction, for ... example) 9. Set speed Command: SPD Keyboard: S Sets the execution speed. Example: 0A SPD 0B 01 ;speed = 1 (fastest) ... (The following commands require OctaMED V2.00 / MED V3.20 or later.) 10. One-shot envelope Command: EN1 Keyboard: E This command allows you to draw the shape of the envelope with the mouse. When the end of the envelope is reached, nothing occurs. 02 40 03 EN1 04 05 Waveform 05 is used as an envelope. Note that the envelope execution starts on next interrupt, so the volume is initialized to $40. The envelope waveform must always be 128 bytes long!! 11. Looping envelope Command: EN2 Keyboard: Shift-E This works like command EN1, except that when the end is reached, execution will start again from the beginning. WAVEFORM/PITCH SEQUENCE LIST COMMANDS ===================================== 1. Set waveform Command: --- Keyboard: --- This command is used to indicate the waveform number (starting from 00). After this instruction, the execution stops until next timing pulse occurs. Don't use waveform numbers that are higher than the actual number of the last wform. Example: 00 00 ;wform 00 01 01 ;wform 01 ... 2. End sequence Command: END Keyboard: --- This command terminates the wform/pitch sequence list. It's always there and automatically inserted. You can't insert commands past this one. 3. Set pitch change down speed Command: CHD Keyboard: D This command sets the sliding speed for sliding pitch down. The sliding automatically starts after this command and stops, when speed is set to zero. Example: 00 CHD 01 03 ;set speed to 3 ... 4. Set pitch change up speed Command: CHU Keyboard: U Just like previous, but slides pitch up. 5. Wait Command: WAI Keyboard: W This command waits for specified amount of timing pulses (pause). Example: 03 WAI 04 02 ;wait for 2 pulses to occur 6. Jump Command: JMP Keyboard: J Causes an immediate jump to another position of the wform/pitch list. Example: 05 JMP 06 0A ;jump forward to line 0A 7. Jump volume sequence Command: JVS Keyboard: Shift-J This command causes a jump to happen in the volume sequence. Can be used e.g. for triggering volume changes after some wform event. Example: 09 JVS 0A 00 ;start volume sequence from the beginning 8. Halt Command: HLT Keyboard: H This has the same effect with command END (halt execution), but it can be inserted in the middle of the sequence list. Example: 03 HLT 04 04 ;some other code (can be accessed with JMP instruction, for ... example) 9. Set speed Command: SPD Keyboard: S Sets the execution speed. Example: 0A SPD 0B 01 ;speed = 1 (fastest) ... 10. Begin arpeggio definition Command: ARP Keyboard: A This command starts the arpeggio sequence. The following values are the arpeggio offsets from the base note. The arpeggio sequence is terminated with ARE-command. The arpeggio starts automatically after the sequence is defined. Example: 03 ARP ;start arpeggio 04 00 ;offset values 05 04 06 07 07 0A 08 ARE ;end arpeggio definition 11. End arpeggio definition Command: ARE Keyboard: E Ends an arpeggio definition. See above. 12. Set vibrato depth Command: VBD Keyboard: V This command is used to set the vibrato depth (00 - 7F). Example: 02 VBD 03 04 ;set depth to 4 13. Set vibrato speed Command: VBS Keyboard: Shift-V This command sets the vibrato speed (00 - 7F). Both speed and depth must be nonzero for vibrato to occur. Example: 02 VBD 03 04 ;depth = 4 04 VBS 05 30 ;speed = 30 14. Reset pitch Command: RES Keyboard: R This command resets the pitch of the note to its initial pitch. (The following command requires OctaMED V2.00 / MED V3.20 or later.) 15. Set vibrato waveform Command: VWF Keyboard: Shift-W Sets the vibrato waveform. The argument is the number of wform. The waveform should always be 32 bytes long!! Note that it's actually played reversed (use the Rev gadget to reverse it). By default, sine wave is used. Example: 00 VBD 01 06 02 VBS 03 40 04 VWF 05 04 ;use wform number 04 as vibrato waveform ============================================================================= Synthsound handling commands in the songs: Command E in the songs controls the MIDI pan, if used with MIDI, but with synthsounds, it is used to trigger a jump in the wform/pitch sequence list. For example, if you wanted to decrease the pitch of the sound after a certain point, your wform/pitch sequence could look like this: 00 VBS 01 40 02 VBD 03 06 04 00 ;play wform 00 05 HLT 06 CHD ;pitch changing entry point 07 02 08 END Now you could compose a track like this: C-2 3000 ;this is the previous synthsound --- 0000 --- 0000 --- 0E06 ;cause a jump to position 06 (pitch starts to slide down) --- 0000 ... With command JVS, you could make the command affect volume sequence too. Hold/Decay: =========== Hold/Decay work well with synthsounds too. The decay value in synthsounds is, however, a jump address in the volume sequence list. When the decay should start, the execution will jump to this entry in the vol seq list. This means that you can handle the decay on any way you want. You can also make it affect the pitch/wforms using the command JWS. Example volume sequence list: 00 40 ;volume 01 HLT ;end 02 CHD ;decay handling (entry point) -> cause decay 03 03 04 END The decay value for this synthsound should be 2. When you save/load synthsounds, the decay values are saved/loaded with the instrument. ============================================================================= Saving/loading synthsounds ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ Synthsounds are saved using the filerequester panel, "save instr". They usually take very little disk space. Synthsounds can be loaded just like normal samples (filerequester, sample list, typing sample name). ============================================================================= HYBRID SOUNDS ¯¯¯¯¯¯¯¯¯¯¯¯¯ Hybrid sounds are much like synthsounds, except that there are no waveform pieces. Instead, there's a normal sample. All commands of the synthsound handling programming language can be used with hybrid sounds. There's only one thing you should know: Don't use "Set waveform". Because there's only a single waveform, there's no need for that (and it wouldn't work anyway). ============================================================================= Final note: Don't be afraid if you didn't understand everything described in this file (I hardly understand it myself ;-) All this information is not necessary for using the synthsounds (only for designing them).