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Pulsar: Pulse to a different drummer


Back in the year 1996, a certain Neil Wakeling coded a unique MIDI program for the Atari platform called Pulsar. It has received many reviews from the UK's Sound on Sound magazine. Today, 2002, it is still going strong, with many new updates as the new version was completed in September of this year. We can now pulse to a different drummer as Pulsar continues to be improved and expanded upon.

[Screen-shot: Pulsar main screen]

What is Pulsar?
Pulsar is a simple riff sequencer, recreating analog-style sequencer effects. It works on three channels at once, each channel having up to 16 notes (individually configurable). All note values and velocities are fully alterable, and can be entered using the mouse or from an attached MIDI keyboard. Each of the three rows has an independent tempo control, and playback of each row can be forwards, reverse, shuttle, or random.

I have had the pleasure of being beta-tester of the new version of Pulsar. It was quite a thrill to be able to suggest a change or idea and have Neil come back with a new version implementing those ideas. We have been working quite a bit the last several months, which now has come full pulse with many new improvements.

[Screen-shot: Pulsar program information]

While in the beta testing process, we exchanged several humorous (to us, anyway!) e-mails regarding the creature Gollum from JRR Tolkien's epic, Lord of the Rings (and now a major motion picture event). Looks like some of this rubbed off into the "About" dialog in Pulsar! There is a grain of truth in the pocket statement. Every time Neil sent me a new version to try out, I would bring home the disk from work in my front pocket. So you could say that Pulsar was in my pocket!

I am now happy to present a tutorial on using the new version, which will explain many of the new functions.

Pulsar tutorial

  1. Starting the program
    Double-click on PULSAR.PRG. Pulsar loads. You are presented with 16 steps for three pitch rows and three control rows (for using continuous controller messages such as volume, panning...). There are parameters for first and last (how may steps you want in the sequence), MIDI channel, transpose, tempo and patch change (P). The control rows contain parameters for MIDI channel, control number, and depth amount.
  2. Using the mouse
    You can change these parameters using the mouse, which has two set-ups: right and left click increments/decrements by one. Holding down the [Shift] key and then right or left clicking will increment/decrement by ten (Shift-clicking). If Pulsar is stopped (not playing) there are several pop-up windows which make selection easier. Once Pulsar is playing, only right and left clicks are accepted so as to not interrupt the continuous flow of Pulsar's output.
  3. Inputting notes:
    Let's first try to input some notes in the pitch rows. There are several ways to accomplish this.
    1. Note input by MIDI keyboard
      1. First mute rows 2 and 3 so we can concentrate on row 1. To do this simply press [F2] and [F3] on the computer keyboard or deselect them using the mouse right on the Pulsar screen under [row on/off]
      2. Using the mouse, go to the Midi menu, then Enter Noterow. A dialog appears asking, "Which Row?" For this tutorial select row 1. Another dialog appears asking you to input notes from your MIDI keyboard. Select Continue, then start playing your MIDI keyboard. You should see the steps in row 1 fill with your selected notes. To hear what you have input, press the space bar or select Play on the Pulsar screen.
    2. Note input by mouse
      Another method is to start Pulsar playing (space bar or select Play) and using the mouse, simply select and change the notes for each step right on the Pulsar screen. The values can be changed right above each numbered step. Having Pulsar playing helps to hear what the sequence will sound like in real-time. One trick with this is to increment the Last parameter a few steps at a time while you are selecting the notes with the mouse. At this point you can try changing some of the velocities (volumes) of each of the steps. This will create a rhythmic feel to the sequence. Values can be changed right below each numbered step. The value can be from 0 to 127. A value of 0 (zero) will create a space in the sequence, which may be desirable for more variation.

[Screen-shot: Pulsar copy function]

  1. Copying rows
    Now that we have some notes in the first row, there is a trick we can do to create even more variation and this is the copy function.

    Go to the menu and under Edit select Copy Row. A dialog appears to ask, "Which Row?" Select row 1. The dialog disappears. The row data are now in a memory buffer. Go back to the menu under Edit and select Paste Row. Again, the question is asked, "Which Row?" Select row 2. After selecting you will see the pitch and velocity values transfer to row 2. We can now do the same for row 3. The data for row 1 are still in the memory buffer, so all we have to do is go back to Edit select Paste Row and select row 3. All three rows now have pitch and velocity data.
  2. Variations and live interaction
    Now that we have all three rows filled up with data, the fun can begin! Un-mute rows 2 and 3 using the [F2] and [F3] keys (or select the rows so they are highlighted on the Pulsar screen). All three rows are now active. Now press the space bar. All three rows should be playing. However, they are identical as we copied the same information to all the rows.
    1. Modes
      To create variation, use the [F4], [F5], and [F6] keys to toggle between the different playing modes that Pulsar offers. These include FWD (forward), shuttle (back and forth), reverse, and random (which I call algorithmic mode). You can also use the mouse for selection as all three rows have these modes displayed on the Pulsar screen.
    2. Transposition
      One of the most fun and interactive parts of Pulsar is the transposition function. This makes use of the numeric keypad:

      Keys for transposing during play: [1]-[9] for 1-9 semitones and [(], [)], [/] for 10, 11, 12 semitones. Also the [Enter] key does the octave keypad 0 for back to no offset.

      While Pulsar is playing, press any of the ten keys. Using this method you can change keys so Pulsar is not static. This idea came from Dr T products such as Tunesmith and Fingers, which make use of this method, so the tradition continues.
    3. Tempo change
      With the new version of Pulsar, you can now set the tempo to 999! This makes for some really fast sequences! There are several ways to adjust the tempo. The easiest way is to use the [+] and [-] keys on the numeric keypad. Another way is to use the mouse. On the transport bar, (under Global) is tempo, which you can click on with the mouse and adjust to a desired value.

      However, these are global adjustments. Pulsar also allows you to adjust tempo for each row, a function not found on most software analog sequencer simulators. This can create polyrhythmic music. To try this and to make it sound musical, set the tempos 100 BPM apart from each other. Example: Row 1: 120, Row 2: 220, Row 3: 320.

      Another trick is to set them in small numbers offset from each other. This creates a MIDI echo effect, which can be quite effective. Try this: Mute row 3, so only rows 1 and 2 will play. Put both rows on FWD (forward) mode as well as the same patch (try a tuned percussive sound like a marimba or vibraphone: patch 9 on a General MIDI module). Set the global tempo to 160. On Row 2, go to the tempo parameter and change it to 165. Press the space bar to start Pulsar. You will hear a MIDI echo effect called "doubling" which is very much used in Tangerine Dream's music. A very nice effect.
    4. Patch change
      Each row has a patch change dialog which is activated by clicking on the "P:" on the far right of each row. Whatever values you enter there will be sent as patch change commands. This enables each row to have a completely different sound.

[Screen-shot: MIDI channel change]

    1. MIDI channel
      While this may not be as obvious, there are many things you can do with MIDI channel change. If you have several MIDI modules, you can set them up with different sounds, so by changing the MIDI channel parameters you are also changing the sounds. Another application is to use Pulsar to generate percussion patterns by changing one or two rows to channel 10 (or whatever channel you use for percussion) while leaving one row open for a bass pattern. Good possibilities here.
  1. Control rows
    Now we come to an interesting part of Pulsar and that is the control rows, which can be used for further timbre variations in the music using "continuous controller" messages. These include volume, panning, sustain pedal, modulation wheel, after-touch... Of course, your synth needs to be able to receive these types of messages to be effective.

[Screen-shot: Control]

    Stop Pulsar if it is playing. On row one, click on the first step of the control row. A dialog will appear with selections of the most used continuous controllers (CCs). For the sake of this tutorial, select Pan. You will see the number 10 appear for step 1 on the controller row (10 for pan). Above the control row is a parameter for the controller depth, or "how much". In the case of a controller such as panning, it will indicate left, right, or in-between and center placements in the stereo field. Using the mouse (and Shift-right clicking) change this value to 127, which will place the sound hard-right.

    Now let's do a trick. Click on the control number of the first step you just created (10). The dialog comes up again. This time select Copy. You will see the panning control number copied to the entire row! Now you can input different values (amount) for each step so you will get a very stereo effect when Pulsar plays. A value of 0 (zero) will be hard-left, 127, hard-right, while anything in-between is toward the center.

    Now let's do another trick! Using the same method we used to copy rows (step 4 of this tutorial) we can apply to control rows. You will notice under edit on the menu, [Copy Control Rows], and [Paste Control Rows]. Just follow no. 4 of this tutorial but substitute copy and past control rows. We now have all the control rows and pitch rows filled in with data. Press the space bar to start Pulsar, and change all the modes for each row to random ( F4, F5, F6 keys) You will hear a stereo delight as the control messages get sent. This works well on General MIDI modules.

  1. Saving and loading
    You will notice under File on the menu the ability to save your settings as Pulsar files (.PUL) as well as saving control rows (.PLC). Once saved you can also load them from this part of the menu. In the Pulsar archive (see file section below) is a folder with many example PUL files as well as control row files. Once you have saved your creation (.PUL and/or .PLC) feel free to load up some of these example files. There is even a file called "ONTHERUN.PUL" which is the sequence used on Pink Floyd's Dark Side of the Moon album for the song, "On the run" (of course). You may need to speed up the tempo on Pulsar to get it to sound right as well as use an analog bass type of sound.

    You can also save a file in the same directory as PULSAR.PRG and name it DEFAULT.PUL, and it will load when Pulsar is started up.
  2. MIDI clock
    Going to the "Midi" part of the menu you will see an interesting dialog that says Midi Song Start. If you select this, it creates a check mark (that is, it turns this function on) so Pulsar sends MIDI clock. This is handy if you are using Pulsar to drive drum machines or to record on external sequencers with a synchronization function. A major addition to Pulsar.
  3. MIDI Spy
    Included with this archive is the program by Codehead Software (and now released as freeware) called MIDI Spy. When used as a desk accessory, you will be able to record Pulsar's output and save it as a standard MIDI file. From there you can import it to your favorite sequencer software to further edit Pulsar files and add to it. Highly recommended. Read the documentation of MIDI Spy. Basically you need to remember to go to configurations and select the MIDI Max option and it will record whatever you do in Pulsar. Very handy indeed! We thought: why re-invent the wheel when this application does a splendid job, so why not use it?
  4. Requirements
    Pulsar works best in ST high resolution. However it also works in the color VGA modes of the TT and Falcon. Perhaps a future version of Pulsar will include a 256-color version with more colors, but time will tell. Pulsar is also Steem-compatible.

Enjoy Pulsar: the Analog Sequencer Simulator.

About Neil Wakeling
[Photo: Portrait of Neil Wakeling]Born in the Highlands of Scotland, Neil Wakeling has been interested in, and playing music since his earliest memories.

As well as being a successful and talented musician he is an electronics engineer with an MSc in Music Technology. He is gifted with a wonderful power of creativity and a deep understanding of the technology and science of sound. This unique combination can be heard distinctly in his music.

The focus and aim of Neil's music is transcendence beyond ourselves. He does this through the use of the sounds of nature combined with electronic composition based on his knowledge of vibrational healing.

Neil has composed a number of albums including soundtracks for television. He organises traditional music workshops as well as healing sound workshops and works one-to-one as a vibrational sound healer.

Program files

  • Latest version of Pulsar (includes MIDI Spy)

Useful links


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MyAtari magazine - Feature #8, December 2002

Copyright 2002 MyAtari magazine