- One commenter thinks that the TI may be the end of the Virus line, it having evolved far from the original Virus A design. What might Access (which has made its name in VA synthesis) follow it up with? I wonder if DSP design has progressed to the point where they could build a new VA that does synthesis by running actual circuit simulations in real time (something that has been speculated on in the Synth-DIY mailing list), and bring it in at a reasonable price point.
- I tend to agree with the posters who can't figure out why the Nord Wave is so pricey. I had thought from the name that it was a follow-on design to the famous PPG Wave keyboards, but it appears that it isn't quite that.
Tuesday, August 19, 2008
V/Wave/TI Review on VSE Forum
Tuesday, August 12, 2008
Whitney's pendulum waveform generator
Since I was unable to find any further information, I made some guesses. My most significant guess is that the device was probably mechanically fairly simple. It would have had the ability to have additional pendulums added or subtracted (Whitney probably experiemented with it to come up with 20 as the optimum number for his purposes), which would seem to preclude any arrangement where all of the pendulums were linked to a single aperture -- it would be too difficult to add or remove pendulums. It probably had no power source other than the pendulums being hand started; since the experimental films in question were quite short, there was no need for the pendulums to run for hours or days on end. We know the pendulums cycled at sub-audio rates because the descriptions mentioned advancing the film very slowly during the imprinting process, so that the sound track would be shifted up into the audio range when the film was projected at normal speed. Also, that's reasonable considering that the fastest-beating pendulums found in mechanical clocks of the day cycled at about 3 Hz, and these were pendulums only a few inches long. (Most clocks had slower pendulums, because the larger mass and higher momentum kept better time and was easier to regulate; our old grandfather clock at home has a pendulum that takes about four seconds to complete one cycle.)
So my guess for the construction of the mechanism is something like this:

20 pendulums in a column file, front to back, with a light path running through them. Each pendulum has a shutter attached to its arm that blocks half of the path with the pendulum at rest; at one extreme the path is full open, and at the other the path is fully blocked. In an idealized form, one can see that the amount of light allowed through by any one pendulum is described by a sine wave (or more specifically, a cosine wave, assuming that all of the pendulums are started by being released from the full-open end of the swing). The light source is placed at one end of the file, and the camera which records the optical soundtrack at the other end. The pendulums all have different effective lengths, and will swing at different rates when released.
One big decision that I had to think about was the light source. Was it a simple light bulb, acting as a point source, or was it a focused beam? Not being able to decide, I resolved to try it both ways. With the setup I described above, it makes a considerable difference. Consider: A point source of light (this is true for sound too) can be visualized as a bunch of rays shooting out in all directions from the source. No two of the rays are parallel; there is always an angle (no matter how slight) between any two, and as you move further away from the source, the rays will spread further apart. If you place any solid obstacle with a cutout opening in front of the point souce, the rays that pass through the opening it will continue to spread out, and so at a sufficient distance, the opening will in turn look like a point source, just weaker. Another obstacle with an opening placed in front of that will, in turn, look like a still weaker point source. This is true even if the obstacles aren't all in a perfect line; some light will still get through. And the effect is enhanced if the light is contained by a reflective tube in between the obstacles.
A beam source behaves differently. In a focused beam, all of the rays (in theory) are parallel; there is no spreading. An obstacle placed in the beam, with an opening that is outside of the beam, will admit no light through. An obstacle with an opening that is in the beam will let some portion of the light through, in a shape that is described by the intersection of the shape of the beam and the shape of the obstacle. If a subsequent obstacle blocks out this part of the beam, then no light will get through at all even though the second obstacle might have an opening elsewhere. Only the light rays that have a straight path through all of the openings can pass. If no such path exists, no light gets through. (Ignoring edge diffraction effects.)
I decided to simulate the second case first. In doing so, in order to simply the math, I made one further assumption: that all of the pendulums had their shutters on the same side, and in the same shape. That is, there would be no case where one pendulum was blocking the left half of the beam and the other pendulum was blocking the right half; a "less closed" shutter would always pass all of the light admitted by any preceding "more closed" shutter. Doing so made the computation of the amount of light passed by all of the pendulums easy; it is simply the least amount of light passed by any individual pendulum, or:
min(pendulum1, pendulum2,pendulum3,...)
I simulated the motion of all of the pendulums as simple sine waves, ignoring nasty real-world unpleasantries such as friction, diffraction, unintentional coupling, etc. I ignored the bit about running all of the pendulums at subsonic rates and speeding them up; I reasoned that in the digital domain, that would have exactly the same result as running the pendulums at higher rates to begin with, so why bother? Instead, I just ran them at audio rates (or nearly) to start with. I figure that the difference in speeds between the slowest and fastest pendulums could not have been huge; probably the slowest pendulum would have cycled once per 5 seconds, and the fastest one at 3-4 Hz at most. And most likely the recording speed was no more than 1:20 of the playback speed; much slower and they would have run into problems with getting a reasonably linear exposure on the film (what the photographers call "reciprocity failure").
I wrote up the sim in Csound and ran it with six different sets of parameters for the pendulum rates. The audio result is here (it is an uncompressed AIFF file, 16-bit, 44.1, mono). There are six different sound samples in the file, each five seconds long, with a short amount of silence in between. The parameters for each sample are:
- Slowest pendulum at 10 Hz, with each additional one 10 Hz higher (20 Hz, 30 Hz, etc.).
- Slowest pendulum at 20 Hz, with each additional one 20 Hz higher.
- Slowest pendulum at 50 Hz, with each additional one 50 Hz higher.
- Slowest pendulum at 1 Hz, with each additional one 13 Hz higher.
- Slowest pendulum at 8 Hz, with each additional one 5 Hz higher.
- Slowest pendulum at 200 Hz, with each additional one 6.33 Hz higher.
Sample 1:

Sample 4 (note the long-period amplitude variation):

Sample 5 (note the mirror-image symmetry of all of the pairs of spikes):

Sample 6 (again, note the mirror-image symmetry):

(I was mildly amused to note, when I imported the files, that all of the waveforms are inverted. I don't know if Csound generated them that way, or if they got that way somehow in the process of importing them into Metro so I could look at the graphs.)
For the second run, I change the simulation from a beam-source light to a point source. In this simulation, each pendulum shutter cuts off a certain percentage of the light, the next one cuts off a percentage of the light that passed through the first one, and so on. If all of the percent-open values are expressed in the range 0-1, as they are in the sim, then the computation becomes:
pendulum1 * pendulum2 * pendulum3 * ...
It's interesting to note that the communativity of multiplication implies that the order of the pendulums does not matter. That seems counterintuitive somehow, yet the math demands that it must be the case. In any case, the results weren't nearly as interesting. I ran it with the same set of parameters as for the first run. Here is the audio file. Nearly all of them came out looking and sounding like the graph below, which is from sample 6:

I'm not sure why these seem so much "orderly" than the samples in the first run; I had halfway expected the opposite. Still interesting, but not quite as much as the first set. Either, though, would have been an absolutely startling thing to hear coming out of a movie projector in 1938! Keep in mind as you listen to these that only a handful of people in the world had been exposed to any kind of electronic music at this point in history.
I plan to do some more work on this. One thing I want to explore: adding friction to the pendulums, in some fashion, to make them "run down". Currently, the pendulums have perpetual motion; they cycle at the exact same amplitude indefinitely. Recall from your high school physics that a pendulum's period depends only on its center of mass; as it loses energy, the cycle rate remains the same, with only the amplitude -- how far it swings to the sides -- decreasing. Having them all run down together, at the same rate per unit of real time, probably wouldn't be very interesting; the overall amplitude would just decrease. However, real pendulums won't do that anway. They will run down according to the number of cycles they have made, or the (angular) distance they have traveled, which means that faster ones run down sooner than slower ones. I want to add that to the sim and see what I get.
I also want to play with some different shutter sizes and shapes. For example, the shutter could be constructed such that the light is totally blocked at the center and open at either end of the swing. Or, it could be cut such that the pattern of variation as the pendulum swings is something other than a sine wave.
Below is the source code for the Csound orchestra (the .orc file). Instrument 101 was used to produce the first run, and Instrument 102 was used to produce the second run. Watch out for line wrap.
; Simulates pendulums with individual aperatures, beam light source
; Assumes aperature is full open with pendulum at 0 deg, full close at 180 deg
instr 101
; Assign initial parameters
ifreq = p4 ; Base frequency
iinc = p5 ; Frequency increment
iscale = p6 ; Output scaling, 0-1
; Table names
itsine = 1
; Compute the phase for each of the pendulums
aph1 phasor ifreq
aph2 phasor ifreq+iinc
aph3 phasor ifreq+(iinc*2)
aph4 phasor ifreq+(iinc*3)
aph5 phasor ifreq+(iinc*4)
aph6 phasor ifreq+(iinc*5)
aph7 phasor ifreq+(iinc*6)
aph8 phasor ifreq+(iinc*7)
aph9 phasor ifreq+(iinc*8)
aph10 phasor ifreq+(iinc*9)
aph11 phasor ifreq+(iinc*10)
aph12 phasor ifreq+(iinc*11)
aph13 phasor ifreq+(iinc*12)
aph14 phasor ifreq+(iinc*13)
aph15 phasor ifreq+(iinc*14)
aph16 phasor ifreq+(iinc*15)
aph17 phasor ifreq+(iinc*16)
aph18 phasor ifreq+(iinc*17)
aph19 phasor ifreq+(iinc*18)
aph20 phasor ifreq+(iinc*19)
; Extract the waveform samples
asine1 tablei aph1, itsine, 1, 0, 1
asine2 tablei aph2, itsine, 1, 0, 1
asine3 tablei aph3, itsine, 1, 0, 1
asine4 tablei aph4, itsine, 1, 0, 1
asine5 tablei aph5, itsine, 1, 0, 1
asine6 tablei aph6, itsine, 1, 0, 1
asine7 tablei aph7, itsine, 1, 0, 1
asine8 tablei aph8, itsine, 1, 0, 1
asine9 tablei aph9, itsine, 1, 0, 1
asine10 tablei aph10, itsine, 1, 0, 1
asine11 tablei aph11, itsine, 1, 0, 1
asine12 tablei aph12, itsine, 1, 0, 1
asine13 tablei aph13, itsine, 1, 0, 1
asine14 tablei aph14, itsine, 1, 0, 1
asine15 tablei aph15, itsine, 1, 0, 1
asine16 tablei aph16, itsine, 1, 0, 1
asine17 tablei aph17, itsine, 1, 0, 1
asine18 tablei aph18, itsine, 1, 0, 1
asine19 tablei aph19, itsine, 1, 0, 1
asine20 tablei aph20, itsine, 1, 0, 1
; Do the min function on all the samples
aout min asine1, asine2, asine3, asine4, asine5, asine6, asine7, asine8, asine9, asine10, asine11, asine12, asine13, asine14, asine15, asine16, asine17, asine18, asine19, asine20
; Output
aout = aout*iscale*20000
out aout
; display aout, .01
endin
; Same as above except the light source is a point source.
; Assumes aperature is full open with pendulum at 0 deg, full close at 180 deg
instr 102
; Assign initial parameters
ifreq = p4 ; Base frequency
iinc = p5 ; Frequency increment
iscale = p6 ; Output scaling, 0-1
; Table names
itsine = 1
; Compute the phase for each of the pendulums
aph1 phasor ifreq
aph2 phasor ifreq+iinc
aph3 phasor ifreq+(iinc*2)
aph4 phasor ifreq+(iinc*3)
aph5 phasor ifreq+(iinc*4)
aph6 phasor ifreq+(iinc*5)
aph7 phasor ifreq+(iinc*6)
aph8 phasor ifreq+(iinc*7)
aph9 phasor ifreq+(iinc*8)
aph10 phasor ifreq+(iinc*9)
aph11 phasor ifreq+(iinc*10)
aph12 phasor ifreq+(iinc*11)
aph13 phasor ifreq+(iinc*12)
aph14 phasor ifreq+(iinc*13)
aph15 phasor ifreq+(iinc*14)
aph16 phasor ifreq+(iinc*15)
aph17 phasor ifreq+(iinc*16)
aph18 phasor ifreq+(iinc*17)
aph19 phasor ifreq+(iinc*18)
aph20 phasor ifreq+(iinc*19)
; Extract the waveform samples
asine1 tablei aph1, itsine, 1, 0, 1
asine2 tablei aph2, itsine, 1, 0, 1
asine3 tablei aph3, itsine, 1, 0, 1
asine4 tablei aph4, itsine, 1, 0, 1
asine5 tablei aph5, itsine, 1, 0, 1
asine6 tablei aph6, itsine, 1, 0, 1
asine7 tablei aph7, itsine, 1, 0, 1
asine8 tablei aph8, itsine, 1, 0, 1
asine9 tablei aph9, itsine, 1, 0, 1
asine10 tablei aph10, itsine, 1, 0, 1
asine11 tablei aph11, itsine, 1, 0, 1
asine12 tablei aph12, itsine, 1, 0, 1
asine13 tablei aph13, itsine, 1, 0, 1
asine14 tablei aph14, itsine, 1, 0, 1
asine15 tablei aph15, itsine, 1, 0, 1
asine16 tablei aph16, itsine, 1, 0, 1
asine17 tablei aph17, itsine, 1, 0, 1
asine18 tablei aph18, itsine, 1, 0, 1
asine19 tablei aph19, itsine, 1, 0, 1
asine20 tablei aph20, itsine, 1, 0, 1
; Do the min function on all the samples
aout = asine1*asine2*asine3*asine4*asine5*asine6*asine7*asine8*asine9*asine10*asine11*asine12*asine13*asine14*asine15*asine16*asine17*asine18*asine19*asine20
; Output
aout = aout*iscale*20000
out aout
display aout, .01
endin
Below is the score file (the .sco file). It is set up for the second run; to change it to do the first run, change all of the instrument numbers from 102 to 101.
; Function tables
; Cosine
f 1 0 16385 9 1 1 90
; base incr ampl
; inst start duration freq ment
i 102 0 5 10 10 1
i 102 5.5 5 20 20 1
i 102 11 5 50 50 0.8
i 102 16.5 5 1 13 1
i 102 22 5 8 5 1
i 102 27.5 5 200 6.33 1
Friday, August 8, 2008
The John Whitney Music Box

Each of the little dots revolves in its own orbit. The period of any given orbit is exactly half of the period of the orbit outside of it. Whenever a dot crosses the positive X-axis, it triggers a synthesized sound at a certain pitch. The revolving pattern produces a fascinating patterns of sounds, repeating about once every five minutes, as the dots orbit about. There are 20 variations, with sounds ranging from plucked strings to chimes to sine-wave harmonics of a given fundemental. The visuals are based on an idea Whitney developed in 1981 (and which was all but unrealizable using the computers of the day); the idea to tie the visuals to the specific sounds and scales is Bumgardner's.
As for Whitney's experiments in sound, I'm aware of two specific things he did. Some years ago, I wrote a very short and silly story about a musician who "recorded" an LP (this was back in the vinyl days) by taking a needle to an acetate master disk and hand-engraving a groove in it. The result was what I called a pseudo-recording: a medium which "plays back" something that was never actually recorded. Not until the first time it is played back is the pseudo-recording ever actually heard, and it is entirely possible that the pseudo-recording's creator has little or no idea what it will sound like until that first playback.
Well, it turns out that Whitney and some other film experimenters actually did something like this. Back in the day, the sound on many movies was encoded directly onto the film in the form of an optical soundtrack, occupying a narrow stripe of the film in between the picture frames and the sprocket holes There were several systems, but usually this was printed on the film negative by a mirror, which reflected a light source onto the soundtrack stripe, and was modulated by a voice coil driven by an audio amplifier, as in a loudspeaker. Whitney, however, produced some experimental animated films where he not only drew the animations, but he also drew the soundtrack. Unfortunately, I haven't yet found any examples of these early animations on the Web. Another idea Whitney had was to produce the soundtrack using an aperture mechanically linked to an array of 20 pendulums, swinging with different periods. Some Web quotes I've found describe the results as sounding highly electronic. I have some ideas about how such a device might have worked, and I'm going to do some experiments to see if I can duplicate the result with Csound.
Returning to Bumgardner for a moment, he synthesized some of the sounds used in the Music Box using a softsynth of his own creation called Syd (as in Barrett, I presume). It looks interesting; its capabilities are, according to the author, based loosely on those of the Buchla 200 modular synth. Unfortunately, it doesn't appear that he is actively maintaining it at this time. Perhaps another enterprising synthesist would be interesting in picking up that baton. (Don't look at me; I've got too many projects going as it is...)
Thursday, August 7, 2008
A studio being born








Friday, July 11, 2008
Inside the V-Synth, Part 5
| Controller | CC # | MIDI Standard Name |
| Modulation function of pitch lever | 01 | Modulation |
| Assignable Knob C1 | 02 | Breath Controller |
| Expression Pedal 1 | 07 | Volume |
| Expression Pedal 2 | 11 | Expression |
| D-Beam L -- Time Trip | 16 | General Purpose Controller 1 |
| D-Beam L -- Time | 17 | General Purpose Controller 2 |
| D-Beam L -- Pitch | 18 | General Purpose Controller 3 |
| D-Beam L -- Assignable | 19 | General Purpose Controller 4 |
| Assignable Knob C2 | 34 | Breath Controller LSB |
| D-Beam R -- Time Trip | 48 | General Purpose Controller 1 LSB |
| D-Beam R -- Time | 49 | General Purpose Controller 2 LSB |
| D-Beam R -- Pitch | 50 | General Purpose Controller 3 LSB |
| D-Beam R -- Assignable | 51 | General Purpose Controller 4 LSB |
| Sustain Pedal | 64 | Hold 1 |
| TT Pad -- Assignable X | 80 | General Purpose Controller 5 |
| TT Pad -- Assignable Y | 81 | General Purpose Controller 6 |
| TT Pad -- Time Trip X | 82 | General Purpose Controller 7 |
| TT Pad -- Time Trip Y | 83 | General Purpose Controller 8 |

- Although the pad operates in R-theta coordinate space when in Time Trip mode, it sends the MIDI data in this mode as X-Y coordinates. This is rather unfortunate because editing the data in a sequencer, and getting the behavior you want, is a non-trivial task. If anybody is really really interested, I'll sit down and work out the trig formulas for it.
- A value of 0 in one of the TT Pad CC messages means that the pad is not being touched. When the pad is touched, both CC messages (for whichever mode is active) transmit with non-zero values.
- The TT Pad Hold button does not send any MIDI itself. It causes the last touched position on the pad to be held, as if you still had your finger on the pad at that point, and this is reflected in the MIDI data. (If send sysex is enabled in the system parameters, it will send a sysex when Pad Hold is turned on and off. This will not effect playback, but it could leave Pad Hold on when you don't want it to. It might be a good idea to delete these sysexes.)
| MIDI Standard Name | CC # |
| 05 | Portamento Time |
| 06/38 | Data Entry |
| 07 | Volume |
| 65 | Portamento |
| 66 | Sostenuto |
| 91 | Effect Level 1 (controls Reverb level) |
| 93 | Effect Level 3 (controls Chorus level) |
| 100/101 | RPN Number |
Parts and Multitimbrality


To set up the USB connection in storage, you connect the cable, go to the mode screen, choose USB, and then (if you have a PC Card in the rear panel slot) choose whether you want the computer to access the V's internal flash memory, or the PC card. After a few seconds, the chosen storage appears as a new drive on your computer; its name will be "V-SYNTH" if you are mounting internal memory, or the name that the card was formatted with ("PC CARD" by default) if you are mounting the card. To terminate the connection, or change to the other storage, use the computer's method for ejecting the drive. Once the drive is ejected, you can press the EXIT button on the V to leave USB mode, or choose one of the two storage spaces to mount again. Sometimes, to re-mount, you have to disconnect and reconnect the USB cable, and sometimes you don't. I haven't figured out what causes that. Currently I have my V connected to a short USB cable which then plugs into a USB extender, and I disconnect and reconnect when needed at the extender.

Sunday, June 15, 2008
Inside the V-Synth, Part 4
Starting With The Basics
The V-Synth's keyboard and bend lever are pretty typical for most Roland models since the late '80s. The five-octave keyboard, C to C, is one of the better synth-weighted keyboards. The keys are full size, have enough travel but not too much, and the stop blocks are just well enough damped. The keyboard is pressure (channel aftertouch) sensitive, and while this tends to be on the heavy side, it doesn't appear to suffer from the pressure sensor degredation of earlier Roland models. Of course, velocity and release velocity are sensed, although I haven't found anything that the V does with release velocity. (The system mode provides sensitivity adjustments for both velocity and aftertouch.) The key edges are blunted just enough to prevent glissandos from being painful, although the black keys do stand a bit high for the purpose. The white key ends have lips of about 1/8-inch, which do not overhang the lower front edge of the case (unlike some earlier Roland models).
The V has Roland's characteristic T-handle combined pitch bend and modulation control. Rocking it left or right affects pitch bend. (The amount of bend is a patch parameter; up and down can be set to different ranges.) It returns to zero reliably without a noticable center detent. Pushing the stick towards the back of the synth adds modulation (which is a routable parameter via the control matrix, explained below). It is spring-loaded in both axes. The modulation axis has a lot of travel compared to most other Roland synths I've played.
Patch Selection and Storage
Many Rolands have a set of eight "bank" and eight "patch" buttons, allowing for eight patches to be selected with a single button press, and 64 patches accessible in a maximum of two button presses. However, the V-Synth has far more patch memory than that -- 512 patch locations. Roland came up with a clever way of addressing this. At the patch main screen, on the left side of the screen is a "List" button. Through this, you can access all patches, in numerical order or by category.
However, 64 patches can be assigned as "favorite" patches, accessible from the patch buttons in addition to the on-screen list. The patch buttons are shown below:

Holding down the assign button and pressing one of the 1-8 buttons assigns the current patch to that button in the current bank. (Note that this does not effect patch memory; the patch remains where it was in the on-screen patch list.) To change banks, hold down the bank button and press one of the 1-8 buttons. If you forget what bank you are on, hold down the bank button and the appropriate 1-8 button will flash; also, the screen will display the names of the eight patches assigned to that bank.
Note that all patches, as well as all PCM sounds and samples on board, are stored in a larger overarching structure called a "project". We'll have more to say about this in the next installment.
Keyboard Transpose
The Keyboard Transpose buttons can transpose the keyboard any desired number of half steps, or quickly transpose by octaves. The latter can be handy when you need to shift the range of the keyboard, say, for a bass or lead patch. These are shown below:

Volume Controls
The master volume controls the output levels of all outputs, including the direct outs and the digital outputs. The external input level knob controls the level of any signal coming in through the external inputs; a red LED indicates clipping. (There are also input preamp gain knobs on the rear panel.) These are shown below:

Programmable Knobs
These two knobs can be programmed in the control matrix to provide real-time control over any desired parameter. One thing to note about them is that, unlike the patch editing knobs, the programmable knobs are "live" the moment a patch is selected; if the knobs are not centered, the parameters they control will be effected immediately. Further, these knobs do not edit the patch; they are like MIDI controllers in that respect. (In fact, they are MIDI controllers. They can be set to transmit MIDI CC messages.) The programmable knobs are shown below:

The Cool Toys: Time Trip Pad
Having gone through the undercard, we now come to the main event. What's the first thing that catches the eye of everyone seeing a V-Synth for the first time? Yes, it's the Time Trip Pad! So how does it work? What does it do? And how about that weird slot in the top of the case labeled "D-Beam"?
The Time Trip pad operates in one of two modes: Time Trip mode, and assignable (or "X-Y") mode. In Time Trip mode, the pad operates in a polar, or R-theta mode. You operate it by placing your finger somewhere on the outer circle, and moving it in a clockwise or counterclockwise direction, quickly or slowly (or you can stop). When you do so, you are taking direct control of the time aspect of the Variphrase processing. Recall that Variphrase makes pitch and time independent parameters. When you touch the pad, time freezes. Moving your finger in a clockwise circle causes time to advance, at the speed you move at. A typical example used to demonstrate it is to set up a patch with a basic vocal sample. Touching the pad and moving your finger in a slow clockwise circle causes the vocal sample to proceed as if the person who was sampled was speaking
veeeeeeeeeerrrrrrrrrrrryyyyyyyyyy
sloooooooooooowwwwwwwwllllllllllyyyyyyyy.
Moving your finger in a fast circle causes the vocal sample to be renderedveryfast! The effect is quite different from rocking a tape reel or scratching on a phoograph because the tone of voice of the sample remains normal. If you go very slowly, you can hear individual sibiliants, clicks, thumps, and transient vowel sounds and vocalizations that we don't normally consciously hear in speech. The effect is quite weird. Moving your finger in a counterclockwise circle causes time to go backwards, so in the case of our vocal sample, it will sound like a reversed tape. Here is the Time Trip pad and its mode buttons:

When you take your finger off the pad, time reverts to advancing normally, unless you have engaged the "Hold" switch to the right of the pad. In this case, the pad retains the last position touched until you touch it again, meaning that time will "freeze" when you take your finger off the pad.
In the Time Trip mode, an additional parameter of your choice can be controlled by how far away your finger is from the center of the pad. This is set up in the control matrix (discussed further down).
When Assignable mode (often referred to as "X-Y" mode in the patch editing screens) is selected, the pad controls two parameters of your choice. One parameter is effected by vertical movement of your finger, the other by horizontal movement. You select which two parameters you want to control in the control matrix. The zero position of the pad is determined by how you set up the parameters in the matrix; normally, this will be the center of the pad, but you can set it up differently if you want. Whenever you take your finger off the pad, the parameters being controlled will revert to zero unless the Hold button is on; in this case, the pad will remember the last position touched until it is touched again.
In either mode, the blue light next to the pad will light whenver the pad is controlling something, either because it senses a touch, or because Hold is on.
Here is a demonstration of the Time Trip pad being used on a vocal sample. The patch has the vocal sample on OSC 1; OSC 2 is off. COSM 1 has a comb fiter selected; COSM 2 is off. The R parameter of the Time Trip pad is controlling the center frequency of COSM 1; you can hear this when I move my finger closer to the center of the pad. At about 1:40, I engage the hold switch. The squealing noise heard in places is an artifact of the low-quality sample.
D-Beam
The D-Beam is an infrared range sensor; it senses how close your hand (or any other object over the panel) is to the sensor. The distance is translated into a value for a control parameter. The sensors are buried in a slot in the panel, with big blue LEDs on either side of it. Depending on the calibration, the D-Beam will trigger whenever an object is 18-24 inches (45-60 cm) above the slot. Note that this may be a problem if you set up the V-Synth on a multi-keyboard stand with another keyboard above it; the D-Beam will sense the bottom of the keyboard above. (I'm having this problem right now; my D-Beam is picking up the bottom of the Juno-106 on the tier above. And I've got that tier as high up as it will go on the stand. I don't want to put the V-Synth on top because the touch screen will be hard to read if it's up too high.) The manual mentions that the useable range may be reduced if the sensor is exposed to direct sunlight. I haven't tried that; I do have the V right in front of a window, and light coming in has not caused a problem. The D-Beam and its mode buttons are pictured below:

Many players who have played with a V-Synth in the store may not realize, and it isn't well explained in the manual, that there are actually two sensors in that little slot. The beams are pretty close together, so just moving your hand randomly over the slot is likely to activate both of them. You have to stay over to the side to only activate one sensor. You can tell when you are doing it right because only the blue LED on that side will light. Operating both sensors independently, with one hand, is a bit of a feat. I've had some success with holding my hand with my index and pinky fingers extended, while the middle and ring fingers are curled in (the "devil's horns" hand sign) and rotating my wrist this way and that to change the relative distances of the two fingers above the sensors.
The D-Beam has four operating modes, which I'm going to address out of order for clarity. The Pitch mode make the D-Beam a pitch bend control. Being that it's a unidirectional sensor, it can only bend in one direction, either up or down depending on how you set it up in the patch. However, if your patch is using PCM oscillators with stereo samples, the two sensors will bend the left and right channels independently, which is pretty cool. The second mode is Time, which instead of pitch bending performs time bending. As you move closer to the sensor, time slows down, while pitch is maintained thanks to Variphrase. Again, if you are using stereo PCM waveforms, the two sensors will operate on the left and right channels independently.
The Assignable mode sets up the two sensors to control two parameters of your choice, per your selections in the control matrix. The Time Trip mode, like the Time Trip pad, is motion rather than position sensitive. To make time advance, you move your hand towards and then away from the sensor cyclically. This is kind of difficult; there is a "turning point" at each end of the travel that you have to reach. If you don't, then when you reverse direction, time will go backwards. I'm not sure how useful this is, considering that the Time Trip pad provides the same effect and is easier to control. Unlike the pad, the D-Beam does not have a hold function.
Arpeggiator
An old favorite that went away a long time ago returns: the arpeggiator. Analolg old-timers will recall that the old Jupiters and Junos (up to the Juno-60) offered an arpeggiator that allowed the performer to hold a chord on the keyboard and the synth would play an arpeggiation of the notes held. The effect was commonly used in the late '70s and early '80s; among other things, it provided a way to simulate the analog step sequencers found on the large modular systems of the day. Here are the arpeggiator panel controls:

Well, this isn't your Juno-60's arpeggiator. The simple front panel controls disguise just how sophisicated the V's arpeggiator is. The on/off button is obvious; it enables or disables the arpeggiator. The knob controls the rate. The hold button causes the arpeggiator to "lock on" to any note struck, even after the note is released. What this is good for will be explained momentarily.
The real capabilities of the arpeggiator are in the patch settings, accessible through the touch screen. The arpeggiation can run a number of different patterns, or "motifs": ascending, descending, alternating, random. It can also arpeggiate the notes in the order that you struck the keys. These do pretty much what you expect. However, you can also build your own patterns, and it's here where some of the power becomes evident. In a user pattern, all notes in the pattern need not have the same time value. Duration as a percentage of the note value can be controlled, and tied/slurred notes can be set up. Rests can also be inserted. Two special motifs that can be used with a user pattern are the fixed motif, in which the pattern actually specifies a fixed sequence of notes (used with drum kit patches), and a motif in which a held key specifies what key the pattern plays in. You can also limit the range of the keyboard over which the arpeggiator operates. This is where the arpeggiator hold button becomes useful: you can play an arpeggiation, hold it, and then play a lead or some other part on the part of the keyboard that is excluded from the arpeggiator, while the arpeggiation continues to run. The default rate is a patch parameter, or you can set it up to sync the arpeggiation to received MIDI Clock messages.
V-Link
The V-Link provides the ability to control an Edirol video pattern generator and display system by what is played on the synth. The intent is to provide synchronized audio and video performances, a concept that flashes back to the late '60s when concerts were frequently accompanied by visuals from slide or film projectors creating abstract patterns. I don't have one of the Edirol video generators, so I can't say much else about V-Link. I will note that, from reading the description in the manual, it appears to take over the MIDI Out port when it is on.
The Missing Button: Portamento
The V has a good portamento capability. All portamento parameters are stored with the patch. Constant-time and constant-rate modes are available; up and down times are independently settable, and a legato mode is available which activates the portamento only when playing legato. So what's missing? There is no button on the panel to turn portamento on and off. I think this is the first synth I've ever seen which had portamento but no panel control for it. To turn it on or off, you have to go into the patch parameters.
Using Your Feet
The V has a hold pedal input and not one but two expression pedal inputs. The hold jack can be set up for either a normally-closed pedal (Roland's standard) or a normally-open pedal (nearly everyone else's standard) in the system settings.
The Control Matrix
All of the V-Synth's real-time controllers -- keyboard aftertouch & velocity, the modulation axis of the bend lever, the assignable knobs, the R dimension of the Time Trip pad, the X and Y dimensions in the X-Y mode of the pad, and the assignable mode of the D-Beam -- are routed to parameters via the control matrix. The matrix has eight source slots, each of which has two destination slots. To set up a routing, you pick an empty source slot and choose a source. Then, you can choose one or two destinations and set the sensitivity of each. There are about 75 possible destinations, so I won't list them here; download the manual from Roland if you're interested. The sensitivity effects how much the controller effects the destination parameter, in either direction; it can be set positive or negative.
In order to record MIDI from the real-time controllers (other than aftertouch and velocity), each controller is assigned to a MIDI Continuous Controller number in the system mode settings. Although it is possible to select a MIDI CC number directly as a source in the control matrix, it will probably be less confusing to use the CC numbers assigned to the controllers. This will be covered in Part 5.
Until Next Time
The next installement, Part 5, will cover all aspects of the V-Synth's audio and MIDI I/O. There are aspects of how the controllers, the arpeggiator, and MIDI interact that aren't well explained in the manual. I'll be doing some research and experimenting on these. Also covered in Part 5 will be the V's USB interface, which is quite powerful but requires some care in setup and use. I'll go through how the V structures its internal storage and show you how to use the USB without fouling up the operating system.
Friday, June 13, 2008
TOSLink





