Aphex IMPULSE The Impulse is a 12 input waveform analysis trigger to MIDI system. It is 3 to 10 times faster than other trigger to MIDI systems tested. The Impulse also includes 4 analog trigger outs for direct trigger or pad inputs, MIDI IN to trigger out, automatic analysis of drum level, re-trigger and crosstalk, MIDI merger, MIDI NOTE OFFS, automatic sensing of input and MIDI NOTE assigns, adjustable velocity curve, 20 patches plus chain mode, real-time velocity display and other bells and whistles that make it (in our opinion of course) the coolest analog to MIDI trigger you can buy. Because the Impulse does not use actual level sensing but computer enhanced waveform sensing, you will find that it is less susceptible to crosstalk and more responsive to quick dynamic changes than other devices you may have tried. We at Aphex thank you for your purchase and commend you on your choice. Aphex Systems Ltd. IMPULSE Manual p. 1 Aphex Systems Ltd. IMPULSE Manual p. 2 IMPULSE: Basic Connections Connections: connections to MIDI devices use standard MIDI cables (5-pin shielded DIN) and follow standard protocols, ie IN to OUT, OUT to IN. Connections from drum pads or pickups (bugs) use standard quarter inch “phono” jacks. Aphex Systems Ltd. IMPULSE Manual p. 3 Basic Controls & Operation: Overview/Introduction: This section will provide you with an overview of all of the Impulse’s screens and functions. It is followed by detailed exercises and explanations for each function. IMPULSE APHEX This is the OPENING SVREEN to the Impulse and appears each time you turn on power to the unit. To move on to the next screen, press the ENTER BUTTON (this is the single button to the left of the cluster of four buttons) and you will be presented with the following screen: ASSIGN SETUP STACKING UTILITY This is the MAIN MENU SCREEN, which is your “home base”. From here, you can move to any of the other screens to access different functions and this is also where you will return when you are done with other screens. The menu of the Impulse is like an elevator with floors up and down and with different departments on each floor. This menu screen is the ground floor. From here, there are four levels (floors) available to you: ASSIGN, SETUP, STACKING, and UTILITY. To move to any of the four levels from the MAIN MENU SCREEN, position the cursor to any of the underlined letters shown above and press the ENTER BUTTON. Lets discuss each level (floor) that you can access from the MAIN MENU SCREEN. INP 01 SND1 STAK CHNL01 NOTE36 C2 ASSIGN SCREEN: This is the screen that let’s you ASSIGN MIDI channels and notes to different inputs (or more correctly, the drums you plug into the inputs – up to 12.) You can also choose if this input is stacking (STAK), crossfading (XFAD), alternating (ROLL), or a fixed velocity (FIXD) output. In addition, each input can output four different MIDI signals or sounds (SND) which you can turn on or off from this screen. These sounds work in different ways depending if you’ve chosen this input to STAK, XFAD, ROLL, or be a FIXD velocity output. Aphex Systems Ltd. IMPULSE Manual p. 4 SETUP AUTO SOURCE MANUAL SETUP SCREEN: This screen is where the Impulse learns your drum kit and automatically sets the level for each drum. In addition, it figures out how much crosstalk there is, etc. You can ask the Impulse to do this automatically for you (AUTO) or you can do it manually (MANUAL). You also select what kind of drum (SOURCE) is plugged into each input, ie. Pad, small drum, or large drum. INP01 s2 s3 s4 STAK% 99 99 99 STACKING SCREEN: This is where you control how the different sounds triggered by each input will respond. You can also turn on or off the different sounds and tell the Impulse at what velocity to bring the different sounds in. You may also choose if the input is FIXD (fixed velocity), STAK (stacking), XFAD (crossfading), or ROLL (alternating) from this screen. UTIL MIDI PATCH DYNAMICS UTILITY SCREEN: This is where we’ve put all the stuff you don’t use. You can turn the MIDI merge on or off (MIDI), store your presets to a computer, make up patches or make up a chain of patches (PATCH) and tailor make the dynamics (velocity) that the Impulse sends out to the kind of sound source you’re using (DYNAMICS). You can also view in real time the MIDI velocities that the Impulse is transmitting. Aphex Systems Ltd. IMPULSE Manual p. 5 Moving Between Screens: Exercise 1 – Using the ENTER BUTTON and the LEFT/RIGHT BUTTONS: Now that we’ve given you a brief introduction to the screens on the Impulse, it’s time to get our hands on the unit and learn how to go from screen to screen. It is fairly painless. First turn on the Impulse and the first screen will be the OPENING SCREEN as shown: IMPULSE APHEX Now press the ENTER BUTTON once (this is the single button left of the cluster of four buttons), and you will be presented with the MAIN MENU SCREEN: ASSIGN SETUP STACKING UTILITY Please look carefully at the first “A” on the screen and you will notice that it is blinking. This is the CURSOR and it is represented in this manual as an underline in our diagrams. Moving between screens and setting any values is done by moving the cursor with a combination of buttons. The buttons you will be using are the following: Aphex Systems Ltd. IMPULSE Manual p. 6 The ENTER BUTTON, which you have just used to go from the OPENING SCREEN to the MAIN MENU SCREEN is used to move between screens. The next set of buttons are the two marked LEFT and RIGHT. These two buttons allow you to move the CURSOR to different positions within any screen. For example in the MAIN MENU SCREEN the cursor is now flashing at the first “A” in ASSIGN. Now, if you press the RIGHT BUTTON once, the CURSOR will move right to the next position on the screen, which in this case is the “S” in SETUP: ASSIGN SETUP STACKING UTILITY (If you were to press the ENTER BUTTON now, you would open the SETUP SCREEN.) Now, if you press the RUGHT BUTTON once again, the cursor will move one more position to the right, which means right and then down to the “S” in the function STACKING: ASSIGN SETUP STACKING UTILITY (If you were to press the ENTER BUTTON now, you would open the STACKING SCREEN. Press the ENTER BUTTON once again, and you will be returned back to this screen) Press the RUGHT BUTTON once more and you will see the cursor move right towards the last position on this screen. Now this time, try pressing the LEFT BUTTON once, and you will see the cursor move back to the left (well, what do you know.) Now that you’ve mastered moving the cursor right and left, you will need to use the ENTER BUTTON to really get moving between the screens. For example, place the cursor over the word ASSIGN (use the LEFT or RIGHT BUTTONS) and then press the ENTER BUTTON once. Presto-chango, you are now on the ASSIGN SCREEN: INP 01 SND1 STAK CHNL01 NOTE36 C2 At this point you will be able to move the cursor using the RIGHT/LEFT BUTTONS (you might want to explore a little bit, but return the cursor to the position shown above before you go on to the next step.) Once you’ve returned the cursor to the position shown above, press the ENTER BUTTON once again, and viola! You have “surfaced” back to the MAIN MENU SCREEN. Aphex Systems Ltd. IMPULSE Manual p. 7 Let’s try the SETUP SCREEN. Use the LEFT/RIGHT BUTTONS to put the blinking cursor ove the word “SETUP” and press enter: ASSIGN SETUP STACKING UTILITY SETUP AUTO SOURCE MANUAL You now have a choice of AUTO, MANUAL or SOURCE. (We must go one level deeper, Scottie! Can the bulkheads hold?!!) Place the cursor over AUTO and press enter again. This is the AUTO SCREEN: A123456789101112 nnnnnnnnn n n n Let’s try and surface all the way back to the main menu. (Slowly now lest the bends set in.) Place the cursor in the upper left corner of the AUTO SCREEN and press enter. Whammo, back up one level to the SETUP SCREEN. The cursor will be sitting in the upper left corner, so just press the ENTER BUTTON again. SHAZAAM – MAIN MENU SCREEN. So that is about as tricky as this whole thing gets. Aphex Systems Ltd. IMPULSE Manual p. 8 Exercise 2 – Using the UP/DOWN BUTTONS: Now, there are two more buttons that you will need to master before we go on; the UP and DOWN BUTTONS. These two buttons are used to select different settings or values that are available for some functions. A quick example will demonstrate the use of these two buttons: If you are doing some exploring on your own and are not currently on the MAIN MENU SCREEN, get to the MAIN MENU SCREEN and move the cursor over to ASSIGN and press the ENTER BUTTON and get into the ASSIGN SCREEN as shown: INP 01 SND1 STAK CHNL01 NOTE36 C2 Move the cursor over to the “0” as underlined and press the UP BUTTON once: INP 02 SND1 STAK CHNL01 NOTE36 C2 Notice the number now reads “02”. (This means you have set the screen for INPut number 2, more on this later.) Keep pressing the UP BUTTON and you will see the numbers change until you get to the number “12” (since there are 12 inputs on the Impulse.) Now press the DOWN BUTTON, and for each press, you will see the number decrease by one until you get back to “01”. Now move the cursor over to the “S” in the word STAK: INP 01 SND1 STAK CHNL01 NOTE36 C2 And then press once on the UP BUTTON and see what happens. You will see it change to the following: INP 01 SND1 ROLL CHNL01 NOTE36 C2 Aphex Systems Ltd. IMPULSE Manual p. 9 Keep pressing and you will see the screen change to FIXD. By pressing the DOWN BUTTON, the screen will display the 4 choices of FIXD, ROLL, STACK and XFAD. Return to STAK and get to the MAIN MENU SCREEN. (Move the cursor over to INP and press the ENTER BUTTON.) SUMMARY: These quick exercises demonstrate the functions of all the buttons on the Impulse. The ENTER BUTTON is for moving between screens. The LEFT and RIGHT BUTTONS move the cursor within a screen, and the UP and DOWN BUTTONS change the value or setting of a specific function within a screen. Now that you can explore the depths of the Impulse menus, why don’t you go and look around for a while. I’ll wait ……………. Hm hm hm….. Oh back? Pick up any trinkets while you were gone? Oh well, maybe next time. Lets look at what each screen does. The following sections will describe each screen in detail. We have also included exploded screen diagrams which show all possible settings where possible. Aphex Systems Ltd. IMPULSE Manual p. 10 ASSIGN Screen: This is the ASSIGN SCREEN. It is reached from the MAIN MENU SCREEN by placing the cursor over “ASSIGN” and then pressing the ENTER BUTTON. INP 01 (01-12) – this value indicates which INPut (up to 12) you are currently viewing. The rest of the screen will reflect what settings are for the input specified. By placing the cursor over the number and pressing the UP/DOWN BUTTONS, you can change the INPUT number displayed from 01 to 12. SND/snd – if SND it means that this SouND is on. (SND #1 is always on.) If it is in lower case it means that it is off. By putting the cursor on the word SND, you may turn the sound on by pressing the UP BUTTON or turn the sound off by pressing the DOWN BUTTON. SND 1 (1-4) – Place the cursor over the number just to the right of SND and press the UP/DOWN BUTTONS over this cursor position and you will scroll through the four sounds (1-4) that are available for each input. STAK (XFAD, ROLL, FIXD) – this displays which of the four effects the Impulse will apply to a signal coming into a specific INPUT. From this screen, you can select one of the four effects by moving the cursor over to the word “STAK” and pressing the UP/DOWN BUTTONS. You will also need to go to the STACKING SCREEN to set the velocities that control how each effect will respond. These effects control how the Impulse will trigger the multiple sounds from a single INPUT. (More about each effect when we go to the STACKING SCREEN.) Aphex Systems Ltd. IMPULSE Manual p. 11 CNL01 (01-16) – this displays which MIDI channel the INPUT will trigger when you hit a drum. You can set any INPUT to trigger any MIDI sound source on any of the 16 MIDI channels. Move the cursor over to the underlined position shown and press either the UP/DOWN BUTTONS until the desired MIDI channel number appears. NOTE36 C2 (12 C0 to 99 D7#) – this specifies which MIDI NOTE NUMBER will be sent out when you hit the drum plugged into this input. You specify which sound by setting its MIDI note number (from 12 C0 to 99 D7#.) IMPORTANT: The Impulse allows you to assign a different MIDI channel and MIDI note number for each of the four sounds that each input can make. That is, you can strike a drum and the Impulse can output four different sounds each on a different MIDI channel. So if you intend to use more than one sound (whether you assign STAK, ROLL XFAD or FIXD), you will need to turn that SND on and assign the MIDI note number and MIDI channel # (CNL#) for each of the sounds you use. Once again, you do this by placing the cursor over the word SND and turn the sound on by using the UP BUTTON and changing the word SND to upper case. Next place the cursor over the sound number (just to the right of the word SND) and use the UP/DOWN BUTTONS to choose which of the four sounds of this input you want to work on. Finally, choose the MIDI channel and MIDI note number for this sound, either manually or by using the neat hidden feature #3 (see below). If you are unfamiliar with the concept of MIDI note values or MIDI channel numbers, we’ll give a brief refresher here. Each sound on a drum machine responds to a MIDI note number that is sent on a particular MIDI channel. When a drum machine receives a MIDI note number it recognizes, it will trigger the appropriate sound. The Impulse can send out 99 note numbers (from 1 to 99) as well as all 16 MIDI channels. (You must always specify the MIDI channel number.) For example, if your drum machine triggers a snare sound on MIDI note 38 and channel #1, you can set INPUT 1 on the Impulse to trigger the snare sound by setting INPUT 1 to note 38, channel #1. If this is becoming complicated, don’t worry. We’ve added a NEAT HIDDEN FEATURE (see below) to the Impulse so that it will learn all the proper MIDI note numbers just by simply playing the sound you want on your drum machine or keyboard. Note: the Impulse, in addition to MIDI note number, also gives you a second set of digits which represents the MIDI note number as a musical note, ie. C2# which means if you use a keyboard to trigger a drum machine, hitting the key for C2# will trigger the sound assigned to it. Unfortunately, not all MIDI instrument makers follow identical standards. Consequently, if a drum sound is triggered at MIDI note #38, Roland assigns a corresponding note number of D2. At the same time, for the same MIDI note #38, Yamaha calls it D1. The Impulse follows the Roland standards. However, the following feature will allow you to operate the Impulse without worrying about MIDI note numbers. Aphex Systems Ltd. IMPULSE Manual p. 12 NEAT HIDDEN FEATURE #1: If you press the ENTER BUTTON while the cursor is over SND1 or CNL or NOTE the Impulse will immediately send out that MIDI channel & note number so you can audition what sound that MIDI channel and note number will make. For example, you see the following screen: INP 01 SND1 ROLL CHNL01 NOTE36 C2 And for the last nickel in your pocket you can’t remember what SOUND 1 is supposed to be. No sweat. Move the cursor to any of the positions indicated on the above screen, press the ENTER BUTTON, and the Impulse will send out, in this example, MIDI note number “36” on MIDI channel “1” to your sound generator and you will hear what the sound is. Change any of the above settings, and the Impulse will audition that setting just by pressing the ENTER BUTTON. NEAT HIDDEN FEATURE #2: If you strike a drum while on this screen, the Impulse will automatically change the INPUT number to match the drum you’ve just hit. For example, you have left your drum kit for a day and when you return, you’ve forgotten how you had wired up your drum kit. No sweat, again. Just set the Impulse to the ASSIGN SVREEN, hit a drum pad, and wham! The INPUT # on the screen will change to show whatever INPUT is for the drum pad you’ve just hit. Neat. Very important: when using this feature, wile the INPUT# will change automatically to whatever drum pad you strike, your drum machine will not sound. Your drum machine will only sound when you press the ENTER BUTTON as described in NEAT HIDDEN FEATURE #1. This is necessary to prevent a “MIDI loop” from occurring. NEAT HIDDEN FEATURE #3: If you plug a MIDI cable from the MIDI OUT on your drum machine (or whatever, drum sampler, etc) and plug it into the MIDI IN of the Impulse, and hit a key or pad on that drum machine, the ASSIGN SCREEN will automatically read the incoming MIDI channel and MIDI note number from the drum machine, and automatically assign it to the INPUT displayed. Here’s a quick real-life example: you’re setting up the Impulse and your drum kit for a gig. You’ve already plugged in your pads and now you need to assign what drum sound will be triggered by each pad. No problem, just go to the ASSIGN SCREEN: INP 01 SND1 ROLL CHNL01 NOTE36 C2 1) Hit the drum you want to assign a MIDI note to. Aphex Systems Ltd. IMPULSE Manual p. 13 2) Hit the pad on your drum machine that you want that drum to sound like. The Impulse will now display the correct MIDI note number and channel of the sound your drum machine just made and assign it to the drum that you’ve just hit. Be sure to hit the drum first, then the MIDI sound. Note: If you don’t see the MIDI note and channel number when you strike the drum machine, make sure that the drum machine or sampler is set to send out MIDI notes and that the MIDI cables connecting it to the Impulse themselves are not a problem. Potential bad thing: Never have “soft thru” or “MIDI echo” enabled on the drum machine or sampler that the Impulse is driving. If you do it will create a MIDI loop that will upset the balance of the earth and send it spinning off it’s axis into deep space. Why doesn’t it work?: The Impulse will not fire your drum machine or sampler while on the ASSIGN SCREEN. This is to help prevent the possibility of MIDI loops. NEAT HIDDEN FEATURE SUMMARY: the easy way to assign the correct MIDI channel and MIDI note value of a drum machine sound to the INPUT you want is to: Step 1) hit a drum pad (NEAT HIDDEN FEATURE #2) which will automatically set the screen to the proper INPUT # for the drum pad you’ve just hit. Step 2) make the sound you want the drum to sound like on the drum machine (NEAT HIDDEN FEATURE #3) which will automatically set the SOUND that you want for the INPUT that you’ve selected it Step 1. Remember, if you want to set a second, third or fourth SOUND for the same INPUT, you will need to move the cursor over the SND# and select the SOUND number you want with the UP/DOWN BUTTONS. Step 3) the easy way to audition any of the sounds you’ve just assigned while in the ASSIGN SCREEN is to move the cursor to either SND, CNL or NOTE and press the ENTER BUTTON (NEAT HIDDEN FEATURE #1). The level of the SOUND heard when the ENTER BUTTON is pressed depends upon the stacking level of the SOUND. That is if the stacking level is 30% then the sound will fire at 30% of maximum velocity. See “STACKING SCREEN” (page 16) for more on setting stacking levels. Aphex Systems Ltd. IMPULSE Manual p. 14 Shortcut: When programming the Impulse, you will find that the ASSIGN SCREEN and STACKING SCREEN are the two most often used screens and you will need to switch between the two. To make this switch easier, rather than always going through the MAIN MENU, you can use the following shortcut: Whenever you position the cursor to the position underlined (shown below) on either screen and press either of the UP/DOWN BUTTONS, you will immediately jump to the other screen. INP 01 SND1 STAK CHNL01 NOTE36 C2 INP01 s2 s3 s4 STAK% 99 99 99 If you press the ENTER BUTTON, you will switch to the MAIN MENU SCREEN, where you can then move to the remaining screens in the Impulse. Note that turning sounds on and off and changing of input effect (STAK, XFAD, ROLL and FIXD) can be done from either the ASSIGN or STACKING SCREENS. Whenever you change a parameter on one of these screens, that change is automatically reflected on the other screen. Aphex Systems Ltd. IMPULSE Manual p. 15 STACKING Screen: INP01 – identifies what INPUT you are on. You can set the screen to display the STACKING status of any of the 12 INPUTS by moving the cursor over the INPUT number and pressing the UP/DOWN BUTTONS. s2 s3 s4 – these numbers represent sounds 2, 3 & 4. The small case “s” means that the SOUND is turned OFF. The upper case “S” means that the SOUND is turned ON. You can turn ON or OFF a SOUND by moving the cursor over the “s” in front of the SOUND number and then pressing the UP/DOWN BUTTONS (cursor positions shown in underline above.) NOTE: SOUND 1 is always ON, after all, what’s the use of an INPUT if it can’t make any sound? If you don’t want a pad to make a sound, just disconnect the pad from the Impulse and throw it in the river. STAK – This controls how the Impulse will treat the SOUNDS assigned to any specific INPUT. You have 4 effects which are described in detail in the next section: STAK: (STAcKing) ROLL: (ROLLing) XFAD: (crossFADing) FIXD: (FIXeD) Aphex Systems Ltd. IMPULSE Manual p. 16 To select any of the effects above, move the cursor to the word “STAK” on the screen and click the UP/DOWN BUTTONS until the desired effect is displayed (cursor position shown underlined above.) If you had previously programmed the screen to another effect (ROLL, XFAD or FIXD), simply move the cursor over the word and click the UP/DOWN BUTTONS until the effect you want is displayed. % 99 99 99 – These numbers indicate the percentage of full velocity. Each effect uses this percent of maximum velocity a little differently. The next section describes in detail what the numbers mean. To change either of the numbers, place the cursor over the underlined positions shown above and press the UP/DOWN BUTTONS until the desired number is displayed. Aphex Systems Ltd. IMPULSE Manual p. 17 The 4 Impulse Effects: The Impulse allows up to four different sounds to be triggered “simultaneously” from any INPUT. Well, it’s actually more than “simultaneous” because you can control and alter how the four sounds are triggered. Rather than hitting a drum pad and hearing four different drum sounds coming out of the drum machine all at once, the Impulse lets you create sophisticated effects with up to four sounds. The four effects are: EFFECT #1 – STAKing: When you hit the drum pad softly, you will hear one sound (a tom, for instance.) Now as you hit the same pad a little harder, you will hear a snare (or any other second sound) added on top of the tom. Hit the pad even harder and you can add a high hat to the snare and the tom. Now kill the pad and you will hear, (get this!) a cowbell, a high hat, a snare and a tom in a pear tree. This effect is note STAKing (or STAK on the screen.) In STAKing, the percent of maximum velocity is where the next sound will start firing. EFFECT #2 – XFADing (or “crossfading”): Hit the drum pad softly and you will hear your favorite tom. Now hit it a little harder, and you will hear a snare as well, but the tom is getting softer! Hit the pad even harder, and you will hear the high hat, a softer snare and an almost quiet tom. Really pound the pad this time and you will hear a cowbell, loud and clear; the high hat softer, a quiet snare, and the tom is gone. The percent of max velocity in crossfading is where the next sound begins and the previous sound begins to fade out. The lower this percentage of maximum velocity is, the more completely the sound will be faded out. EffECT #3 – ROLLing: This effect rolls or alternates between the different sounds. Notice that there is no percent of velocity in the ROLL SCREEN. This is because each alternating sound responds to how hard you hit the pad (or drum) in the same way. Let’s try it out. Hit the drum pad and your tom sound fires. Hit the pad again and you will hear the next sound which is the snare. Hit it one more time and you will hear the high hat and just the high hat. One more hit and you will get the cowbell. And if you hit the pad a fifth time, you get your tom back. The Impulse just rolls between the four sounds you’ve chosen, each strike on the pad triggers the next sound and keeps rolling round. Of course, if you have set only two or three SOUNDS, the Impulse will just roll between those two or three SOUNDS. The ROLL effect is useful for preventing “sample cut-off”. Sometimes when you hit a drum before the sample has finished, the sample will start giving a “machine gun” effect. If this is not desirable, some drum machines and samplers allow different MIDI notes to fire different samples of the same sound. In that way you may hit the drum again before the sample is over and the sample will not be cut off, instead a new sample of the same sound will simple begin. Aphex Systems Ltd. IMPULSE Manual p. 18 Another use of the ROLL effect is to assign four slightly different conga sounds or triangle or cowbell sounds to one of your pads. You can then play just one pad and get the effect of being a “Latin whiz”. EFFECT #4 – FIXeD: This time when you hit the pad up to four sounds will sound at once, except each sound will be triggered at a single, fixed velocity (or loudness) regardless of how hard you hit the pad. All you need to do it to tell the Impulse how many SOUNDS you want for each INPUT, and how loud you want each SOUND to be. If you use fixed velocity, the Impulse will output MIDI in less than 1 millisecond. This will appear instantaneous to your ear. Fixed velocity is often used in recording. Note that the percent of max velocity of each sound is the velocity that the sound will have. Therefor you can create a layer of sounds and tailor the velocity of each component of the layer to get just the composite sound you’re looking for. Aphex Systems Ltd. IMPULSE Manual p. 19 Programming the 4 Impulse Effects: NEAT HIDDEN FEATURE #4: When you place the cursor over SND1 or s2, s3, s4 or the percentages underneath them and press the ENTER BUTTON, the Impulse will audition that sound for you. This is useful if you forget what SOUND you have assigned to any particular INPUT. This feature is extremely useful in helping you program the following effects quickly: SELECTING EFFECTS: INP01 s2 s3 s4 STAK% 99 99 99 Each of the 12 INPUTS can be assigned it’s own effect. The default settings are shown above and show that we are looking at INPUT #1. The STAK effect is assigned as default, although SOUNDS 2, 3 & 4 are turned off (see next section). If you leave an assigned INPUT at these default settings (SOUNDS #2, 3 & 4 are OFF), the Impulse will function as if no effects had been selected, ie: if you were to hit the drum pad, you would only hear the assigned SOUND at whatever velocity you had hit the pad with. To change INPUTS, position the cursor over the INPUT # as shown underlined above and then press the UP/DOWN BUTTONS until the desired INPUT # appears. To select effects other than STAK, position the cursor over the word “STAK” shown by the underline above, and press the UP/DOWN BUTTONS until the desired effect is displayed. Programming each of the four effects is described below: Aphex Systems Ltd. IMPULSE Manual p. 20 Programming STAK : INP01 s2 s3 s4 STAK% 99 99 99 Note: Assigning the MIDI notes and MIDI channel to each of the sounds in the STAK is done on the ASSIGN SCREEN. Once the sounds have been assigned, then switch back over to the STACKING SCREEN. INP01 S2 S3 S4 STAK% 33 45 80 In this example, we can see that we are currently looking at INPUT #1. (If you switch over to the STACKING SCREEN and the INPUT # is not the one you are working on, move the cursor over to the INP# and press the UP/DOWN BUTTONS until the correct INPUT # is displayed.) The above screen also shows that all four SOUNDS are turned ON since the letter “S” by each SOUND # is in upper case. SOUND 1 is not displayed because it is always on. You can turn on or off each SOUND by moving the cursor over the letter “s” beside each SND # and pressing the UP/DOWN BUTTONS, toggling between lower-case (SOUND OFF) and upper-case (SOUND ON). In the above screen, when you hit the drum pad at less than 30% of full velocity, only SOUND 1 will be heard. Once you reach 33% of full velocity, SOUND 2 will be added to SOUND 1. At 45% of full velocity, SOUND 3 will be added to SOUNDS 1 & 2. At 80% and above all four SOUNDS will be heard simultaneously. Changing any of the above STACKING PERCENTAGES will change the levels at which additional SOUNDS will be stacked onto SOUND 1. If you want all four SOUNDS to track together, then set the STAK% at 0 for all four sounds. Aphex Systems Ltd. IMPULSE Manual p. 21 Programming XFAD: The XFAD (crossFADe) screen is similar to the STAK SCREEN. However, the settings have different effect when then INPUT is triggered. The following example will demonstrate the effect. INP01 S2 S3 s4 XFAD% 20 40 60 In this example only three SOUNDS are used as indicated by the upper case “S” by SOUND #2 and 3. Remember SOUND #1 is always ON, and consequently is not displayed in this screen. SOUND #4 is turned OFF as indicated by the lower-case “s”. Of course, you can turn off or on SOUNDS #2-4 by moving the cursor to the underlined positions shown and pressing the UP/DOWN BUTTONS to change the case of the displayed “s”. The numbers below indicate the percentage threshold at which each SOUND begins to crossfade with the previous SOUND. Percentage numbers are set by placing the cursor over the underlined positions and pressing the UP/DOWN BUTTONS until the number desired is shown. In this example, when INPUT #1 is triggered below 20% of full velocity, only SOUND #1 will be heard. However, when 20% of full velocity is reached, SOUND #2 will begin to replace or crossfade with SOUND #1. At 40% of maximum velocity and above, SOUND #3 will begin to crossfade with SOUND #2 while SOUND #1 will probably be all the way off. By setting the XFAD% (crossfading points as expressed in percentage of full velocity), you will be able to set whether SOUND #1 will be all the way gone or just quiet. In addition, if SOUND #4 were turned ON, then when INPUT #1 is pushed to 60% of maximum velocity, then SOUND #4 will begin to crossfade with SOUND #3 while SOUND #2 becomes quieter and SOUND #1 will be inaudible. Aphex Systems Ltd. IMPULSE Manual p. 22 Programming ROLL : INP01 S2 S3 S4 ROLL In this example of the ROLL effect, note that there are no percentage figures shown in this screen. This is because the ROLL effect switches or “rolls” between different SOUNDS regardless of velocity. The loudness of each sound will depend on how hard you hit the pad each time. In this example, SOUNDS 2, 3 & 4 are all turned ON (upper-case “S”) and when the INPUT is triggered, SOUND #1 will be sent out at the velocity at which the INPUT was triggered. The next time the same INPUT is triggered, the Impulse will “roll” to SOUND #2. The third time it is triggered, SOUND #3 is sent out. And when triggered the fourth time, SOUND #4 is heard. Then the Impulse will “roll” back to SOUND #1 and so on. Of course, if less than 4 SOUNDS are turned on, the Impulse will only “roll” between the number of selected SOUNDS. Programming FIXD : In the FIXD (FIXeD) effect, all SOUND(S) will be sent out at a predetermined velocity regardless of the INPUT velocity. INP01 S2 S3 S4 FIXD99 70 60 50 In this example screen, SOUNDS #2, 3 & 4 are all turned ON in addition to SOUND #1 which is always ON by default. Notice, however, that there is an extra percentage number. The first percentage number represents the preset velocity of SOUND #1. As shown above, SOUND #1 is set at 99% (which means full velocity), SOUND #2 is set at 70% of maximum velocity, SOUNDS #3 and 4 are set at 60% and 50% respectively. Now, when you hit the drum pad for this INPUT, regardless of how hard you hit the pad, SOUND #1 will be sent out at full velocity, SOUND #2 will be sent out at 70%, SOUND #3 at 60%, and SOUND #4 at 50%. Be careful if you set and SOUND # to 0% of maximum velocity, which means that SOUND will not be heard at all. Aphex Systems Ltd. IMPULSE Manual p. 23 SETUP Screens: SETUP AUTO SOURCE MANUAL The SETUP SCREENS are for programming the Impulse to learn the characteristics of your drum kit (acoustic, pads, or a mixture of both). Since all drums behave differently, the Impulse must learn how to react to the analog signal generated by each type of drum so that when you hit that drum during a performance, the Impulse will react properly. There are two modes in which the Impulse can learn your drums kit: automatically and manually. The automatic mode is fast, and will get you within the ballpark of the optimum responses for your drum kit. The manual mode is slower of course, but can give near-perfect response. We recommend, especially when you first begin to use the Impulse, that you use the automatic mode first to set up your entire drum kit, then as you play with your kit, come back to the manual mode to fine-tune the Impulse for optimum performance. In any case, you must first tell the Impulse what type of drum (pad, small drum or large drum) is plugged into each input. Selecting the Setup Screens: From the MAIN MENU, place the cursor on the word “SETUP” as indicated by the underline below: ASSIGN SETUP STACKING UTILITY Then press the ENTER BUTTON and you will now be in the SETUP MENU SCREEN: SETUP AUTO SOURCE MANUAL In the SETUP MENU SCREEN, you have three choices to select from (as indicated by the underlines): Aphex Systems Ltd. IMPULSE Manual p. 24 SOURCE: In this screen you will select the type of drums (PDAS, Small DRUM, or LaRGe DRUM) that you are using for each INPUT in your kit. AUTO: This screen allows the Impulse to automatically analyze the characteristics of your specific kit – the number of drums used, the individual response of each drum, and the crosstalk levels of each drum as well as the entire kit. MANUAL: This screen allows you to manually fine-tune the response of the Impulse to your kit. Preparation for Setup: To prepare for using either AUTO or MANUAL SETUP, make sure that all the drums in your kit that you intend to use are connected to the Impulse. Connecting all the drums in a kit is necessary for the Impulse since it needs to be able to measure the entire setup for effective crosstalk suppression. Then go to the ASSIGN SCREEN and assign at least one SOUND for each INPUT used. Assigning at least one SOUND for each INPUT before running SETUP is necessary because as you test your setup, you will need to hear how it is triggering your sound generator. SOURCE SETUP: Next, go to the SOURCE SCREEN and select which type of drum is plugged into each input. The SOURCE SCREEN appears as follows: INP# 01 SM SRUM Place the cursor over the INPUT number and use the UP/DOWN BUTTONS to choose the INPUT number you are working with. Place the cursor over the drum type and again use the UP/DOWN BUTTONS to select the type. You may choose from 3 drum types: SM DRUM = small acoustic drums LRG DRUM = large acoustic drums PAD = electronic pad triggers Aphex Systems Ltd. IMPULSE Manual p. 25 AUTO SETUP: The AUTO SETUP SCREEN appears as follows: A123456789101112 nnnnnnnnn n n n Placing the cursor over the letter “A” as shown by the underline and pressing the ENTER BUTTON will return you back up one level to the SETUP MENU SCREEN. The numbers on the top row represent the 12 available INPUTS. The lower case letter “n” underneath each INPUT # indicates that the Impulse has not yet analyzed or calibrated that particular INPUT. Now, to auto-analyze each INPUT: 1) Select the first drum (in this example, this drum will be connected to INPUT #1). Note that it is not necessary to do anything but strike the drum you want the Impulse to analyze to begin the process. Hit the drum as hard as you expect to hit it when playing or at the maximum velocity you want that drum to be set to. Pause for at least 5 seconds or until the drum dies down. Then strike the same drum again for four more times for a total of 5 times, pausing between each strike long enough for the drum to completely die down. Try to be consistent in striking the drum (like an engineer trying to get a snare sound and asking you to play it 400 times exactly the same.) This is exactly what the Impulse is trying to do as you strike the drum repeatedly; it is setting its own internal gain controls and measuring crosstalk levels. When the Impulse has heard 5 hits and has successfully analyzed the drum, the lower-case “n” beneath the appropriate INPUT # will change to an upper-case “Y” (YES) as below: A123456789101112 Ynnnnnnnn n n n In addition, if you have your drum machine/sampler/keyboard connected, the sound will trigger. (The input will not trigger the drum machine until analysis is completed.) Aphex Systems Ltd. IMPULSE Manual p. 26 2) Auto-analyze the remaining drums as in Step 1 above until all the drums in your kit have been finished. 3) That’s it for AUTO SETUP. If this is your first time on the Impulse, you can go ahead and try out your setup. If you want to re-analyze any particular drum after you’ve tried it out, you can simply go to the AUTO SETUP SCREEN, place the cursor over the “Y” of the INPUT you want to re-analyze, press the DOWN BUTTON to revert it to an “n”, then re-strike the drum pad as in Step 1 above. You can re-analyze any number of individual INPUTS without disturbing the calibration on other INPUTS. It is recommended that the auto-analyze routine be done twice if you are in a condition in which crosstalk is a severe problem. AUTO SETUP Notes: For the AUTO SETUP mode to function at optimum performance, you will need to keep a few guidelines in mind: 1) Do not touch any drum other than the one you are analyzing when using the AUTO mode and do not touch the drum you are analyzing until after you have made the five hits necessary for calibration. Otherwise, the Impulse will mistakenly interpret your accidental touch as crosstalk. 2) Make sure that the Impulse receives exactly 5 hits to the drum on each INPUT before the screen displays successful analysis (when the “n” changes to a “Y”). If less than 5 hits are made, then the REJECTION LEVEL (in MANUAL SETUP – see next section) must be raised since the Impulse is interpreting a delayed ringing as a trigger. If more than 5 hits are required, then check the pickup and/or cable for damage. The Impulse is not receiving all the signals from the drum. 3) If you are using a drum pad (pads made specifically for electronic triggering), make sure that the REJECTION level is not less than 30. If you are using an acoustic drum as a trigger (a drum which has been fitted with a “bug” to act as an electronic trigger), make sure that the REJECTION level is not less than 60. To set the REJECTION level, you will need to go to the MANUAL SETUP SCREEN to set the recommended levels. For detailed information on use of the REJECTION level setting, please read the next section “Manual Setup”. Aphex Systems Ltd. IMPULSE Manual p. 27 4) If you finish AUTO SETUP and go to another screen, and later you decide to recalibrate any or all of the drums in your kit, when you return to the AUTO SETUP SCREEN, you will find that all the INPUTS will display “n” (lower-case). This does not mean that the previous auto-analysis has been forgotten, but rather that only the screen display has been reset for further analysis. If you analyze only some of the INPUTS, the other INPUTS previously set will remain at their prior settings. MANUAL SETUP: After using AUTO SETUP, you may find that you might still want to tweak the response of a specific pad or the entire kit for an even better response. The MANUAL SETUP SCREEN allows you to fine tune all the parameters for each individual pad in the kit. From the SETUP MENU SCREEN place the cursor over the word “MANUAL” and press the ENTER BUTTON. You will see: #01 LVL01 SLF000 REJ 015 OTHR 048 #: When the cursor is underneath this symbol, pressing the ENTER BUTTON will move you back up one level to the SETUP MENU SCREEN. 01: This number indicates the current INPUT# for the screen. Place the cursor over the position indicated by the underline shown above and press the UP/DOWN BUTTONS to select the other INPUT #S. LVL01: Means the gain setting for this INPUT. There are 16 different gain levels, 01 to 16. “01” being the least sensitive and “16” being the most sensitive. This setting affects individual INPUTS and affects the way the analog section alters the gain of the specific INPUT for maximum dynamics. For example, if your pickup or drum’s output signal is weak, the digital section of the Impulse will not be able to read 100% velocity for that INPUT. Consequently, setting a higher gain level will make it possible to sense maximum velocity. However, setting too high a gain will result in clipping, ie: even if you hit the pad softly, the output will still trigger maximum velocity. The gain essentially affects the “dynamic” range of the drum pad. SLF000: This is the SELF REJECTION LEVEL and the numbers can be set from “000” to “255”. This is one of the forms of crosstalk the Impulse can control and the numbers represent the MIDI velocity times 2 (x2) that a drum pad’s INPUT must reach if the same drum is to be re-triggered within 200 milliseconds. Aphex Systems Ltd. IMPULSE Manual p. 28 This type of crosstalk is primarily found in large percussion devices such as an open tom. Like a kettledrum, once hit, the reverberations can rise (ring) a moment later and cause the Impulse to re-trigger. To control this effect, for example, you could set a SLF level of 080, which means that t he Impulse will not re-trigger for the first 200 milliseconds after the drum is hit unless the second trigger exceeds a velocity of 040 (setting divided by 2). Thus, a SLF level set higher than the “ring” level effectively prevents undesired re-triggering. Of course, setting the level too high means that if you actually do want to trigger the INPUT again, you would not be able to do so within 200 milliseconds unless you hit it hard enough to go over the SLF threshold. If the drum re- triggers after the 200 millisecond (sort of a delayed echo) then increase the REJECTION until this condition stops. See REJECTION below: REJ015: This is the REJECTION level. Settings are from “000” to a maximum of “255”. The higher the REJECTION level, the less apt the Impulse is to fire off a MIDI note when a drum is excited. The lower the REJECTION level, the more apt the Impulse is to fire. The REJECTION level affects all 12 INPUTS. Regardless of which INPUT # you are currently working on, setting the REJECTION level will set it for all 12 INPUTS. The REJECTION level’s function is to eliminate any ambient or external acoustic sources, which can accidentally trigger a pad. This is especially true if you use an acoustic kit. For example, if your audience begins to clap loudly, or if your monitors are placed too close, etc. and your drums get excited enough, they will begin to trigger. The REJECTION level setting allows you to set a bottom level at which these extraneous sources of noise are rejected by the Impulse. Setting the level too high, however, will reduce the dynamic range of your kit. In addition, REJECTION is the “court of last resort” in eliminating crosstalk in general. OTHR000: This setting represents the minimum MIDI velocity level times 2 (x2) that a drum must reach for the Impulse to trigger if it is excited within 15 milliseconds of another drum. Settings range from “000” to a maximum of “255”. The purpose of OTHER (OTHR) level is to control crosstalk between the different drums within a set. For example, if you hit one drum, the vibrations might travel (through your rack, etc.) to another drum in your kit and cause it to trigger. The Impulse eliminates this type of crosstalk by the OTHER setting. It works because sound travels at approximately 1 foot per millisecond. Now, it is unlikely that your drum kit will be greater than 15 feet in size (beyond 15 feet there is very little chance of crosstalk.) Therefore, if one of the INPUTS is triggered, crosstalk will occur on any other drum within 15 milliseconds. At the same time, crosstalk is much weaker than the original signal, so if the Impulse receives a second trigger within 15 milliseconds of another drum, it measures the velocity of a second trigger and if it is less than the OTHER setting, it Aphex Systems Ltd. IMPULSE Manual p. 29 will disregard the trigger and not let it pass. Consequently, proper setting of the OTHER level will eliminate most of the crosstalk in any kit. Setting it too low will allow crosstalk to pass, but setting it too high might also prevent you from intentionally triggering a drum within 15 milliseconds of another drum. NOTE: when using the AUTO SETUP, the Impulse will automatically set all of the levels shown in the MANUAL SETUP SCREEN, except the REJECTION level. You can then use those settings as a beginning point for fine-tuning in MANUAL SETUP. A REJECTION level of at least 30 is recommended if you are using pads as triggers. A REJECTION level of at least 60 is recommended if you are using acoustic drums as triggers. Since the REJECTION setting affects the entire kit (not just a single INPUT), if you are using a mixture of pads and acoustic drums in your kit, you will need to set the REJECTION level for the overall response of the entire kit. If your kit is primarily acoustic drums, you will need to set the REJECTION level higher. If your kit is primarily pads, then the REJECTION level can be set lower. See the “APPLICATION NOTES” for more details on fine-tuning the response of the Impulse. Aphex Systems Ltd. IMPULSE Manual p. 30 UTILITY Screens The UTILITY SCREEN looks like this: UTIL MIDI PATCH DYNAMICS There are 3 screens available through the UTILITY SCREEN: 1) MIDI SCREEN – this screen allows you to set: a) MIDI merge b) MIDI NOTE-OFFS 2) PATCH SCREEN – this screen allows you to: a) Save Impulse settings as a patch for later use b) Chain different patches to quickly switch between different Impulse settings 3) DYNAMICS SCREEN – this screen allows you to: a) Modify the dynamics of your setup b) See a display of real-time velocity Aphex Systems Ltd. IMPULSE Manual p. 31 MIDI Screen Contained in the MIDI SCREEN are MIDI MERGE and MIDI NOTEOFFS. MERGE When MERGE is ON, incoming MIDI DATA, say from an OCTAPAD will be MERGEd with the outgoing data that the Impulse creates. To turn MERGE on, put the cursor over the word “OFF” and press the UP BUTTON to change OFF to ON. To turn the MERGE OFF, put the cursor over the word “ON” and pres the DOWN BUTTON to change ON to OFF. BE CAREFUL OF MIDI LOOPS! If you have a drum machine plugged into MIDI IN and MIDI OUT of the Impulse and have MERGE ON and have SOFT THRU or MIDI ECHO turned on in the drum machine a MIDI loop will be created in which the ultimate effect may be to upset the balance of the Earth and send it spinning off its axis into deep space. You wouldn’t want that on your conscience would you? Think of Disneyland! Think of ice cream Sundaes! Think of Top 40! Well, why not… The MIDI MERGE on the Impulse is designed to allow instruments like an OctaPad or drum machine percussion part to be merged with normal Impulse MIDI data. It is not designed to merge an entire sequence full of information. If you do, you may find that merged notes may be missed during heavy input processing. The Impulse is designed as a lightning fast drum trigger first and a MIDI MERGE second. NOTE-OFFS INPUTS 9 thru 12 are capable of generating MIDI NOTE-OFFS. The NOTE- OFFS are used when the Impulse is driving a sound source that’s making a non- percussion sound, say a horn sound. If the Impulse didn’t send the MIDI NOTE-OFF the horn sound wouldn’t stop. Place the cursor over the INPUT # and use the UP/DOWN BUTTONS to choose the INPUT(s) you want to send MIDI NOTE-OFFS on. Notice the number to the right of the INPUT number. It will tell you how long before the MIDI NOTE-OFF is sent. The default is 00. This means that this INPUT is not sending a MIDI NOTE-OFF. Each Aphex Systems Ltd. IMPULSE Manual p. 32 number from 01 to 50 represents 1/10th of a second before the MIDI NOTE-OFF is sent. Therefore, 35 means the MIDI NOTE-OFF will be sent 3.5 seconds after the NOTE-ON. A 23 means the MIDI NOTE-OFF will be sent 2.3 seconds after the NOTE-ON. The settings of MIDI NOTE-OFFS are available as a PATCH. This means in one PATCH, INPUT 9 may send MIDI NOTE-OFFS after 2.3 seconds, but in another PATCH, INPUT 9 may not send MIDI NOTE-OFF at all. Notes: 1) Results may vary depending upon how your sound source responds to multiple MIDI NOTE-ONS or multiple MIDI NOTE-OFFS, both of which are possible when quick drum hits are combined with slower NOTE-OFF timings. 2) Programable note-offtimings on inputs 9-12 are not operative when the INPUT has been selected as a ROLL type. PATCH Screen This screen enables the saving of the machine state into a PATCH or Preset. The PATCHes may be then strung together in any order into a CHAIN. PATCH: To save a PATCH (current machine state) put the cursor over the PATCH number you want the current machine state to be saved under. Use the UP/DOWN BUTTONS to change the PATCH number. Press the ENTER BUTTON and the display will change from SAVE to OK telling you the save has been made. To recall a PATCH, go back to the MAIN MENU SCREEN. Use the UP/DOWN BUTTONS to select the PATCH. The red 7-segment LEDs on the front panel will display the PATCH number you’ve selected. The PATCH is automatically installed when you see it’s number on the front panel red 7-segment LEDs. You can also use a latching foot switch plugged into the footswitch jack on the back of the unit to change Aphex Systems Ltd. IMPULSE Manual p. 33 PATCHes. A mono footswitch will move PATCHes up only. A stereo latching footswitch will move PATCHes both up and down. In addition you can recall a PATCH via MIDI Program Change. The Impulse listens on MIDI channel 16. Transmit a program change out MIDI channel 16 into the Impulse’s MIDI IN and the appropriate PATCH will be recalled. Note that program changes above 20 will be ignored. CHAIN: First call up every sleazy… oh, never mind. Put the cursor over the word “chain” (lower-case) and press the UP BUTTON to change it to CHAIN (upper-case). The display will now look like this: PATCH CHAIN CHAIN 01 PATCH01 The number to the right of CHAIN is the CHAIN position number. The number to the right of PATCH is the PATCH that is placed in that CHAIN position. For example, CHAIN07 PATCH03 means that PATCH 3 is the 7th in the CHAIN. To change the CHAIN position, put the cursor over the CHAIN number and use the UP/DOWN BUTTONS. To change the PATCH number to be put into that CHAIN position, put the cursor over the PATCH number and use the UP/DOWN BUTTONS. To step through the CHAIN, use the same method as stepping through patch numbers. That is, use the UP/DOWN BUTTONS or footswitch while the Impulse is on the MAIN MENU SCREEN. You may step through the CHAIN from the MAIN MENU SCREEN using the UP/DOWN BUTTONS or by using the footswitch. Just like recalling PATCHes, sending program changes will specifically recall a patch number and not a chain location. NOTE: If you try to recall a PATCH and all you see is “01”, make sure you are not in CHAIN mode by mistake. Aphex Systems Ltd. IMPULSE Manual p. 34 DYNAMICS Screen The DYNAMICS SCREEN looks like this: For each MIDI velocity that goes out of the Impulse, you can select another MIDI velocity to be sent instead. For example, if the REAL MIDI VELOCITY is 45, the CURVE (MIDI VELOCITY that is sent out) can be set to 55. This is used to tailor the output of the Impulse to fit with the various sound sources available. This is how to change the MIDI VELOCITY CURVE. Put the cursor over the REAL MIDI VELOCITY number and use the UP/DOWN BUTTONS to scroll to the REAL MIDI VELOCITY number that you are interested in. Then place the cursor over the CURVE MIDI VELOCITY number and use the UP/DOWN BUTTONS to select the CURVE MIDI VELOCITY number of your choice. NEAT HIDDEN FEATURE #5: When you play a note while on this screen, the Impulse will show you in real time what REAL MIDI VELOCITY and CURVE MIDI VELOCITY are being sent out. This is especially handy when triggering from tape and it is necessary to augment the DYNAMICS because the original signal has been compressed. You are able to see exactly what MIDI VELOCITIES to augment. NEAT HIDDEN FEATURE #6: Sometimes you want to offset an entire range of velocities. It is inconvenient to change each number in the range (though you are certainly entitled to do so) so here’s a short cut: 1) Scroll the REAL MIDI VELOCITY to the top or bottom of the desired range. 2) Adjust the CURVE MIDI VELOCITY as needed. 3) Press the ENTER BUTTON. 4) Scroll the REAL MIDI VELOCITY to the other end of the desired range. 5) Press the ENTER BUTTON again. Each MIDI VELOCITY number within the range will be offset the chosen amount. Ta da! Aphex Systems Ltd. IMPULSE Manual p. 35 HOW TO BAIL OUT: If you have decided that the curve you have set up is not working, then place the cursor over the word “ARGH” (stands for AARGH!!!) and press the ENTER BUTTON. The default curve will be re-installed. Aphex Systems Ltd. IMPULSE Manual p. 36 Analog Pulse Outs On the back of the Impulse you will notice four jacks labeled “Pulse Outs”. These are used to trigger older style drum machines and samplers that require a “trigger in”. INPUTS 1 through 4 automatically generate an analog pulse out. INPUT 1 will generate a pulse on PULSE OUT #1, INPUT #2 will generate a pulse on PULSE OUT #2, and so on. You may also cause the Impulse to fire an analog pulse out via MIDI. If a MIDI NOTE ON is sent into the MIDI IN of the Impulse, it is checked with the MIDI NOTE NUMBER and CHANNEL NUMBER of SOUND 1 of each of the first four INPUTS. If there is a match with the MIDI NOTE and CHANNEL assigned to that INPUT then that INPUT will fire the corresponding ANALOG PULSE OUT. For example, if INPUT #2, SOUND 1 is assigned to MIDI NOTE #42 and MIDI CHANNEL 3, and MIDI NOTE #42 is received on MIDI CHANNEL 3, an analog pulse will fire from PULSE OUT #2. (Note that the extra stacking sounds 2, 3 & 4 of the inputs are not checked, only SOUND 1 of each input is checked for a MIDI match.) RESETTING THE IMPULSE The Impulse can be completely reset to factory default settings by simultaneously pressing the ENTER, LEFT and RIGHT BUTTONS while turning the power off and on. WANING: this procedure will completely erase all presets that you have created and the original factory settings will be loaded instead. Aphex Systems Ltd. IMPULSE Manual p. 37 Closing: The Impulse triggering system is a product that Aphex is proud of. You will find a balance of power and simplicity – accuracy and speed. A computer product designed for musicians. Thank you for your purchase. Aphex Systems Ltd. IMPULSE Manual p. 38 APPLICATION NOTES FOR DRUM TRIGGERING OVERVIEW Triggering MIDI devices from drums is not a perfect science. It may never be because there are seemingly as many variables as there are drummers, clubs, concert halls and recording studios. Each situation is different. The same drum set may react differently in tonight’s club date than last night’s studio session when you had different heads on the toms. The permutations are endless. We feel that the Impulse is a significant step forward in the technology required to handle the majority of percussion triggering situations. However, there are limits to every electronic device. Because of this, we have prepared these application notes, which we hope will guide you through some of the more common problems that can occur as well as dispel some myths about drums and triggering systems. (ie: Drums were not invented by Buddy Rich.) Aphex Systems Ltd. IMPULSE Manual p. 39 TRIGGERING FROM PADS Pads are the easiest and most straight forward application for any triggering system. Electronic drums with piezo pickups mounted on a piece of wood covered with a rubber playing surface are designed to give excellent trigger pulses. They are also, by design, less prone to normal crosstalk because they do not create sound by themselves. However, we have discovered that the rack systems which have become popular for mounting these pads can be problematic for two reasons. First, the clamp which holds the mounting arm of the pad must not be allowed to rotate when the pad is struck. When this happens, the movement of the clamp causes vibrations to be sent out that could be interpreted by the Impulse as a second hit. Secondly, the rack itself can begin to vibrate in what can be described as a “standing wave” which may be picked up by the pad and transferred to the Impulse. We recommend that the rack system for mounting pads be as tight as is practical at all clamp points and be played on a carpeted surface, if possible. Aphex Systems Ltd. IMPULSE Manual p. 40 TRIGGERING FROM TAPE The replacement and reinforcement of drums recorded on tape with sampled sounds has become the accepted standard for many types of recording. The idea is that an engineer can use the drum sound on tape as you would a drum with a pickup to trigger sound sources using a trigger interface. Some engineers blend the sound of the recorded drums with the samples being triggered. Problems arise when drums are recorded very “hot”, causing tape saturation and compression. In essence what happens is that the transients are lost. Since the Impulse relies on these transients, dynamics and triggering accuracy may be compromised. Also, leakage from one drum mic to another may cause the Impulse to false trigger. Plug the leakage-causing drum into another input on the Impulse to activate the anti-crosstalk feature. An expander may help in rescuing lost transients. If other drum crosstalk persists, raise the rejection floor until the crosstalk goes away. See your manual under SETUP for further explanation. Aphex Systems Ltd. IMPULSE Manual p. 41 TRIGGERING FROM ACOUSTIC DRUMS There are probably more misconceptions about triggering MIDI devices from acoustic drums than any other subject in the electronic music field. It even has been suggested tat it is impossible and that MIDI cannot work as an interface for this application. We feel that the MIDI protocol is not the problem, but the understanding of the physics of drums that has been neglected. We found during our research that many factors are involved in the translation of acoustic drum wave forms to MIDI note outputs for triggering a drum machine or sampler. Many times “MIDI delay” is blamed for slow triggering. Actually, at least some of the problem is in the way people have been setting up their drums for triggering. Let’s look at this more closely: PICKUP PLACEMENT Where a pickup is placed on a drum has dramatic impact not only on the sensitivity, but also the response time of the triggering system. A pickup placed on the head of the drum is the best position for quickly picking up the transient of a drum hit. One of the reasons pickups are placed inside drum shells is that it reduces crosstalk from other drums. However, this placement can slow down the triggering by as much as 3 milliseconds – since it takes that long for the shell of the drum to start moving, and in turn vibrating the pickup. In other words, if you mount it inside the shell, it’s gonna be slower. It’s just physics. Because the Impulse is not as susceptible to crosstalk as other triggering systems, it is not necessary to mount the pickups inside the drum. The Impulse will, however, work with shell-mounted “Drastic Plastic” pickups when located near the head of the drum. Aphex Systems Ltd. IMPULSE Manual p. 42 PICKUP TYPE There are two basic piezo pickup types: 1) “Door Buzzer” piezos, which you can buy at Radio Shack for $2.95 or your local music store for $29.95, and 2) Small piezos which have been “dipped” in a vinyl or plastic. (Barcus Berry drum pickups are an example of this second type.) We recommend this second type (“dipped”). They can improve drum triggering speed by as much as three times over the “door buzzers”. This is because the “dipped” pickup has less mass to move, and therefore reacts more quickly. Simple, huh? So, if you mount your “door buzzer” inside the shell, your gonna get slower triggering. DRUM SIZE The size of the drum and the way it is tuned also has an effect on the triggering speed of any drum to MIDI interface. The sound wave form takes longer to develop as the size of the drum increases. The Impulse is less susceptible to this effect than most drum triggering systems, but if you have not followed our previous recommendations, we guarantee slower response time than if you had. On bass drums, the closer you can mount the pickup to the beater, the quicker the Impulse will respond and the less it will be bothered by after ring. Some of the same physics apply to larger toms as to bass drums, with the additional problem of the drum being out of tune. Make sure that the head your pickup is mounted on is tuned evenly. Aphex Systems Ltd. IMPULSE Manual p. 43 MOUNTING PICKUPS ON RUM HEADS Mounting a pickup on a drumhead may not be as easy as using the supplied sticky tape or putty. These supplied adhesives do not always work on coated drumheads (ie: Remo Ambassadors). You may have to scrape away the coating where you are mounting the pickup. Double sided sticky tape or “putty” does not necessarily allow good “coupling” between the head and the pickup. A thin coat of contact cement is recommended for most drumheads. When changing heads, you can carefully remove and clean the cement from your pickup with a razor knife. Aphex Systems Ltd. IMPULSE Manual p. 44 CROSSTALK The Impulse is extremely adept at handling crosstalk in most setups. However, there are situations in which the software will get swamped by excessive crosstalk. We have discovered that this occurs when two drums are hit simultaneously and repeatedly in quick succession. What will happen is that occasionally one drum will not fire consistently. If this situation occurs, first check the physical setup of the kit to reduce the amount of crosstalk being transmitted by the rack. Then raise the rejection level in small increments as you retest your kit until the crosstalk disappears. We suggest beginning at a minimum rejection level of 35; however, you should experiment to determine which level would best meet your particular requirements. Aphex Systems Ltd. IMPULSE Manual p. 45 CAUTION These applications apply to the use of the Aphex Impulse. The recommendations we have made may not work with other percussion triggering systems. The Impulse is a unique device incorporating patented analog circuitry detecting incoming signals and copyrighted digital software, which converts those signals to MIDI information. Aphex Systems Ltd. IMPULSE Manual p. 46 TRIGGERING PROBLEMS & SOLUTIONS PROBLEM SOLUTION 1. Sound is too quiet Increase level (LVL) 2. Goes to MAX VELOCITY too quickly Decrease level (LVL) 3. Same drum re-triggers Increase SLF 4. Drum re-triggers after ¼ sec. Increase rejection (REJ) 5. Other drums fire Increase other (OTHR) 6. Drum won’t fire at low level Decrease rejection (REJ), or Increase level (LVL) 7. Erratic firing Check pickup and cable 8. Velocity is inconsistent Check assigned drum type 9. Drum machine goes crazy Check for MIDI loop 10. Speakers fire drums Increase rejection (REJ) 11. Neighbors call police Turn up volume Aphex Systems Ltd. IMPULSE Manual p. 47 This document was created with Win2PDF available at http://www.daneprairie.com. The unregistered version of Win2PDF is for evaluation or non-commercial use only.