

Quick Intro
-----------

This document is a miniature user's guide (patch parameter guide)for the JP-8080. It contains most of chapter 3 which deals with patch parameters and some parts of chapter 4 of the owner's manual for the JP-8080 copyrighted by Roland. In addition, there are over 50 additional notes written by me which are mostly about the inner-workings and little-known features of the synth (although almost everything applies to the JP-8000, too). i decided to type in this guide for the benefit of the JP-8000 inspired VSTI project and for those of you without the manual. Even if you do have the manual, browsing through the extra notes might still be a good idea in case there's something new.


Conventions
-----------

============...: Indicates a main chapter heading (Level 1 heading in HTMl).
------------...: Means a sub-heading in a chapter (would be a level 2 or level 3 heading in HTML).
*** Additional Note #nn ***: Signals a note by me (every note has a unique number associated with it).
[]: A bullet character (filled square on paper).
**: Hint, there's some extra information provided by Roland.
* : A note concerning the operation of the JP.
[PARAMETER): If a word is in upper case as well as being bracketed, it is a parameter name.
<snip>: Some text is leaved out (an additional note will usually explain why).

I've also manually numbered the chapters, headings and notes so that it is easier to find what you are looking for (use the find function provided by practically every text editor). The chapter numbering differs from that of Roland's.


0 Table of Contents
===================

1. Functions that Modify the Sound
1.1. Selecting the Basic Waveform for the Sound (1) (Oscillator 1)
1.2. Setting the Basic Waveform for the Sound [2] (Oscillator 2)
1.3. Using the External Input
1.4. Modifying the Waveform and Pitch of the Sound
1.4.1. OSC COMMON (Oscillator Common) Section
1.4.2. PITCH ENVELOPE Section
1.5. Modifying the Brightness
1.5.1. FILTER Section
1.5.2. FILTER ENVELOPE Section
1.6. Modifying the Volume
1.6.1. AMP (Amplifier) Section
1.6.2. AMP ENVELOPE (Amplitude Envelope)
1.7. Modifying the Sound (LFO 1)
1.8. Making Effect Settings (Effects)
1.8.1. Adjusting the High and Low TOne (Tone Control)
1.8.2. Adding Spaciousness and Depth to the Sound (Multi Effect Level)
1.8.2.1. Changing the Type of Multi Effect (Multi Effect Type)
1.8.3. Adjusting the Echo effect (Delay)

2. Taking Advantage of the Performance  Functions
2.1. Playing Single Notes (Solo Switch)
2.2. Playing Analog Synthesizer-like Solos (Envelope Type in Solo)
2.3. Adding Cyclic Changes (Modulation (LFO 2))
2.4. Smoothly Changing the Pitch between Notes (Portamento)

3. Credits



1. Functions that Modify the Sound
==========================================


Chapter 3 explains the sound- related parameters. All of the parameters Explained in this chapter can be set independently for each Patch.
It is a good idea to first use PANEL SELECT [LOWER]/[UPPER] to make sure of the patch for which you are making settings.


1.1 Selecting the Basic Waveform for the Sound (1) (Oscillator 1)
-----------------------------------------------------------------

The OSC 1 (Oscillator 1) section selects the waveform that is the basis for the synthesizer's sound.

[WAVEFORM]/[CONTROL 1]/[CONTROL 2]

[WAVEFORM] selects the OSC 1 waveform, and [CONTROL 1]/[CONTROL 2] modify parameters unique to that waveform.

When you move [CONTROL 1]/[CONTROL 2], the display will show the name of the parameter that is being edited.
In the following explanation, [CONTROL 1] will be listed as [1]), and [CONTROL 2] as [2].

[] SUPER SAW

This sounds like seven sawtooth waveforms sounding simultaneously. Pitch-shifted sounds are added to a central sound. It is especially suitable for creating thick string-type sounds, and allows you to produce a thick sound even when the Key Mode is Single.

[1] DETUNE:

Adjust the degree of pitch detuning. As the knob is rotated to the right, the pitch will be detuned more greatly, making the sound more spacious.

[2] MIX:

Adjust the volume of the detuned sounds relative to the central sound. As the knob is rotated to the right, the detuned sounds will become louder, making the sound thicker.


*** Additional Note #01 ***

A huge number of sawtooth waveforms can be layered by enabling the unison mode on the JP. However, the sound is not as "phat" as you might expect. I think some of the saw waveforms partially cancel each other out.


[] TRIANGLE MOD (Triangle Modulation)

This is a modification of a triangle wave, with a large number of overtones. Since there is much energy in the overtones and little in the fundamental, the result is similar to applying an HPF (high pass filter, p.73) to a squarewave.

[1] OFFSET:

Specify the way in which the triangle wave will be shaped. As the knob is rotated to the right, the waveform will be modified more significantly, producing a greater proportion of overtones.

[2] LFO 1 DEPTH:

Adjusts the amount of effect which LFO 1 (p.77) will have when it is applied to Offset. As the knob is rotated to the right, Offset will change more.

*** Additional Note #02 ***

The triangle mod may be just a high-pass filtered squarewave. Tweaking the Offset sounds like it changes the cutoff frequency of the highpass filter.

[] NOISE

By applying a LPF (low pass filter, p.73) to noise many different "colors" of noise can be produced.

[1] CUTOFF FREQ:

Set the cutoff frequency of the LPF. As the knob is rotated to the right, the noise will have more high frequency components, and at the same time the volume will also increase (Rotating the knob to the left all the way may result in no sound at all.) Also, since the cutoff frequency will change depending on the key that you play, the noise will change. The cutoff frequency will rise as you play higher notes, and will fall as you play lower notes.

[2] RESONANCE:

This regulates the emphasis that is applied to region at the cutoff frequency. As the knob is rotated to the right, the sound will have a greater sense of pitch. If the knob is rotated to the right all the way, a sine wave will result.

** Characteristics for high values of RESONANCE

When RESONANCE=127, a sine wave will result, producing a pitched sound. At this time, setting CUTOFF FREQ=64 will cause the pitch to correspond to the key that is played. As the CUTOFF FREQ value is changed in steps of one, the pitch will change in semitone steps. You may find it convenient to use the Edit Scope (p.64) to view the value as you make settings.

*** Additional Note #03 ***

Based on the resonance characteristics, I would guess that the filter is a 4 pole one. The noise sounds like white noise if the filter is fully open and you play a relatively high note. You get a sine wave if you set Resonance to max because  the filter is self-oscillating.

*** Additional Note #04 ***

The cutoff of the LPF of the noise oscillator can be modulated by modulating OSC1 pitch or the global pitch with an LFO or an envelope. The cutoff will even respond to portamento but not to filter key tracking. Note also that in legato mode (not in poly mode or in mono mode) there's some "portamento" for the cutoff frequency even if portamento was turned off.  The portamento or gliding for the cutoff frequency happens only if you play legato.

[] FEEDBACK OSC (Feedback Oscillator)

This sound is similar to electric guitar feedback. It is suitable for creating hard and aggressive sounds that stand out.

* If FEEDBACK OSC is selected, SOLO SW [MONO] or [LEGATO] will be turned on, and notes will play monophonically. It will  not be possible to turn off [MONO] or [LEGATO], nor will it be possible to turn [UNISON] on.

[1] HARMONICS:

Vary the sound of the harmonics.

[2] FEEDBACK AMOUNT:

Adjusts the amount of feedback to adjust the level of the harmonics.

*** Additional Note #05 ***

If both oscillator controls are set to zero, the basic sound of the feeddback oscillator resembles a sawtoothwave.


*** Additional Note #06 ***

You cannot synchronize the feedback waveform but ringmodulation and cross modulation (frequency modulation) are both possible.


[] Square wave

This sound is similar to a woodwind instrument. It also is widely used in making typical "synthesizer" sounds.

[1] PULSE WIDTH:

Set the width (pulse width) of the square wave. As the knob is rotated to the right, the pulse width will change, producing a sound with more overtones.

[2] PWM DEPTH:

This technique of applying LFO 1 (p.77) to the Pulse Width is referd to as PUlse Width Modulation (PWM). PWm Depth determines how greatly PWM will be applied. As the knob is rotated to the right, Pulse Width will be modulated more greatly, creating a broader and more "smeared" sound.

[] Sawtooth wave

This waveform is used for nearly all instruments except for woodwinds. Many sounds unique to synthesizers can be created using this waveform.

[1] SHAPE:

Specify the degree to which the sawtooth wave will be deformed. When the knob is at either end of its range, the sound will have a strong fundamental, and will be suitable for thick bass sounds etc. When the knob is in the center position, the sound will be thin, as though an hpf was applied to it.

[2] LFO 1 DEPTh:

When LFO 1 (p.77) is applied to Shape, this parameter specifies how greatly Shape will be affected. As the knob is rotated to the right, Shape will be affected more greatly.

** Shape for sawtooth waveforms

Sawtooth wave sounds on diffrent synthesizers differ in subtle ways, and the sound of a sawtooth wave often determines the character of the synthesizer itself. On the JP-8080 you can use Shape parameter to make fine adjustments to sawtooth waves, for an even greater range of sound-creating possibilities.

*** Additional Note #07 ***

The sound of the sawtooth wave is a bit different in both ends of the shape scale.

[] Triangle wave

This is a simple sound with few overtones. it is used for creating flute sounds etc.

[1] SHAPE:

Specify the degree to which the triangle wave will be deformed. As the knob is rotated to the right, the waveform will be modified more greatly, producing a sound with more overtones. This will produce a sound similar to square wave with an LPF (low pass filter, p.73)applied to it.

[2] LFO 1 DEPTH:

When LFO 1 (p.77) is applied to Shape, this parameter specifies how greatly Shape will be affected. As the knob is rotated to the right, Shape will be affected more greatly.


<snip>


*** Additional Note #08 ***

Ttriangle waves can be modulated similarly to square waves by lengthening one side and shortening the other. However, I'm not sure if that's how the triangle modulation is done on the 8080. Also, Ring modulation will be covered later in the Osc 2 section, that's why I left some text out which was saying just that, that ring modulation will be dealt with later on.


1.2. Setting the Basic Waveform for the Sound [2] [Oscillator 2]
----------------------------------------------------------------

*** Additional Note #09 ***

As for Oscillator 2, there's no point in rewriting or pasting the same information included for osc 1. Thus I will only include passages describing the differences between the oscillators.

In the same way as for the OSc 1 section, this selects the waveform that will be the basis of the sound. By combining OSC 1 and OSc 2, a variety of sounds can be created. You can also input audio from an external source without using the OSC 2 waveform.

[WAVEFORM]/[CONTROL 1]/[CONTROL 2]

[WAVEFORM] selects the waveform of OSC 2. Only when square wave and noise are selected, [CONTROL 1]/[CONTROL 2] will modify parameters unique to these waveforms.

[] Square wave

<snip>

[] Sawtooth wave

<snip>
[] Triangle wave

<snip>

*** Additional Note #10 ***

You cannot modify the tone color of the triangle and sawtooth waves for oscillator 2 with controls 1 and 2.

[] NOISE

<snip>

Unlike NOISE for Osc 1, the cutoff frequency will not change, regardless of the key that you play.

*** Additional Note #11 ***

Modifying pitch in any other way such as by LFOs, the envelope or with portamento has no effect to the cutoff of OSC 2 NOISE either. The only way to modulate the cutoff is to physically rotate the knob.

[SYNC] (Sync Switch)

This switches sync on/off. When this is on, the indicator will light, and a complex sound with many overtones will be produced. This is effective when OSc2 pitch is higher than the OSC 1 pitch.
Sync causes the output waveform of OSc 2 to be synchronized to the output waveform of OSC 1. ("Functions using OSC 1 and OSC 2" (p.73)). I.E., each time the OSC 1 waveform returns to the beginning of its period, OSC 2 will also be forcibly reset to the beginning of its period, producing a complex waveform.

* If the effect of Sync is difficult to notice, rotate [OSC BALANCE" towards the right (towardsOSC 2).
* Sync will not occur if NOISE is selected as the OSC 2 [WAVEFORM], or if [EXT] is on.

*** Additional Note #12 ***

As a comment to the ladder note, unlike on Clavia Nord Lead 2.

*** Additional Note #13 ***

For more information on oscillator synchronization, head to the corresponding article on my Web-page:
http://www.student.oulu.fi/~vtatila/sync.html


** Tonal changes using Sync

If you turn [SYNC]] on and modify [FINE/WIDE], the tone of OSC 2 will change in various ways while the pitch remains the same.


[RANGE]

Specify the pitch of OSc 2 in relation to OSC 1 over a range of +/-24 semitones (+/-2 octaves). As the knob is rotated towards the right the pitch of OSC 2 will rise. As it is rotated toward the left  the pitch of OSC 2 will fall. With a setting of 0, OSC 2 will have the same pitch as OSC 1.
With settings of -WIDE or +WIDE, the [FINE/WIDTH] knobs can adjust the pitch of OSC 2 over a +/-4 octave range.
However in this case, you must be sure to rotate the knob fully right or left.

* To make it easy for you to make accurate settings, the -24, -12, 0, +12  and +24 settings have a greater width than other settings.

*** Additional Note #14 ***

With extremely low or high pitch settings in which LFOs and the pitch envelope further modulate the pitch, the feedback waveform makes really cool and strange sometimes aliased noises. The effect is more prominant if you use the octave buttons to shift the patch as low as possible as well as adjusting the feedback osc to have the maximum amount of feedback.

[FINE/WIDE] (Fine tune/Wide)

When the [RANGE] setting is -24 - +24, this knob provides a +/-50 cent (+/-1/2 semitone) adjustment to the pitch specified by the [RANGE] setting. As the knob is rotated to the right, the OSC 2 pitch will rise. As it is rotated to the left, the OSC 2 pitch will fall. When this knob is in the center position, the pitch will be as specified by the [RANGE] setting.
When the [RANGE] knob is in the fully left (-WIDE) or fully right (+WIDE) position, this knob can be rotated towards the left to adjust the pitch -4 - 0 octaves, or towards the right to adjust the pitch +0 - +4 octaves.

* To make it easy for you to make accurate settings, the center setting has a greater width.

** Giving the sound more spaciousness

If you select the same waveform for OSc 1 and Osc 2, set [RANGE] to 0 and use [FINe/WIDE] to create a slight difference in pitch, the sound will appear more spacious (the detune effect).

RING (Ring Modulation Switch)

This switches the Ring Modulator on/off. When this is on, the indicator will light, and the sound will become more metallic. This is suitable for creating bell sounds, etc.
The ring modulator multiplies the OSC1 waveform with the OSC2 waveform, producing a sound that contains many overtones not found in either of the original waveforms. ("Functions using OSc 1 and OSC 2", p.73). SInce large numbers of inharmonic overtones are present, the sound will have a dissonant , um-pitched feeling.

* The sound with the newly-generated overtones will be generated by OSC 2 so if the result of the ring modulator is difficult to detect, rotate the OSC COmmon (OSC BALANCE) towards right (towards OSC 2).

*** Additional Note #15 ***

There are no limitations on using the ring modulator. You can even modulate the special waveforms like supersaw, the feedback and the noise waveform. External audio can be ringmodulated as well.


1.3. Using the External Input
-----------------------------

Audio from an external source can be input via the external EXT IN jack or the MIC jack. In this case, it will not be possible to use the OSC 2 waveform.
Settings related to external input can be made in [EXT] (External Input Switch) of the OSC 2 section, and in the EXTERNAL INPUT section.

When only one jack is connected

VOCAL/UPPER: The sound wil be input only to the UPPER part.
INST/LOWER: The same sound will be input to both parts (LOWER/UPPER).

The sound which is input from the INST/LOWER jack can be used as the OSC 2 of the lower part.

The sound which is input from the VOCAL/UPPER jack or the MIC jack can be used as the OSc 2 of the Upper part.

The sound which is input from the MIC jack will be amplified by the mic amp. The sound which is input from the ET IN VOCAL/UPPER jack will be used at its original level.

In the same way as for the OSC 2 waveform, sound will be produced only while note-on messages are being received.

(EXT) (External Input Switch))

WWWHen [EXT] is turned on, the [WAVEFORM] will automatically be turned off, the sound from the EXT IN jack or MIC jack will be input.

To turn [EXT]) off, press [WAVEFORM] to select a waveform for OSC 2.

Also, when [EXT]) is on, [CONTROL 1] will control the following parameter .

[1]] GATE THRESHOLD:

THis sets the minimum input level. Only sounds that are louder than the specified level will be input.
No parameter is assigned to [CONTROL 2].

*** Additional Note #16 ***

In other words, control 1 will set the threshold level for the noise gate which processes external audio. Anything below the threshold will be cut. Unfortunately you cannot have control over the attack and release times of the gate.

** EXTERNAL INPUT section

[REAR/FRONT) (Vocal Input Select Switch)

Specify whether you will be using the VOCAL /UPPER jack or the MIC jack.

[REAR/FRONT) specifies which jack will be used. When off (REAR), the EXT IN VOCAl/UPPEr jack is used; when on([FRONT), the MIC jack is used.

This parameter can be set independently for each patch / performance.


[INST/LOWER]/[VOCAL/UPPER] (Input Level)]

Adjusts the volume of the external input. If even a small amount of sound is input, the SIC/LIMITer indicator wil light green.

The limiter will operate on sounds which exceed a specified level, automatically adjusting the volume to keep the sound from distorting. When this happens, the SIC/LIMITER indicator will light red.

IF you want the sound to have dynamic expression, adjust it so that the SIC/LIMITER indicator lights red occationally.

* The external input sound is frequently used for the VOice Modulator function (p.103) or the External Trigger function (p.121).


1.4. Modifying the Waveform and Pitch of the Sound
--------------------------------------------------

In the OSC COMMOn (Oscillator Common) section and PITCH ENVELOPE (Pitch Envelope) sections, you can make settings that affect both OSC 1 and OSC 2.

1.4.1. OSC COMMON (Oscillator Common) Section
---------------------------------------------

[OSC BALANCE] (Oscillator Balance)

This adjusts the balance betweeen OSC 1 and OSC 2. As the knob is rotated towards the left, the volume of OSC 1 will become louder. As it is rotated towards the right the volume of OSC 2 will become louder. In the center position, OSc 1 and OSC 2 will have the same volume.

*** Additional Note #17 ***

The balance control appears to be a cross-fading mixer between the two oscillators. In other words, the amplitude of the sum wave produced by the two oscillators should be nearly a constant regardless of the balance setting.

[OSC SHIFT [-OCT]/[+OCT]] (Oscillator Shift)

Shift the pitch that is produced when you play your MIDI Keyboard, in one-octave steps. This allows you to play notes which fall above or below the actual range of notes on your MIDI Keyboard. It is convenient to use this method when you whish to change just the Patch of a specific part in Dual or Split modes.
Pressin [-OCT] will lower the pitch in one-octave steps, and pressing [+OCT] will raise the pitch in one-octave steps.

*** Additional Note #18 ***

Portamento will be covered in chapter 2, because for some odd reason it's put in a difrent chapter from most other patch parameters in the original user's guide.


[X-MOD DEPTH] (Cross Modulation Depth)

Cross Modulation is when OSc 2 modify the frequency of OSC 1 ("Functions using OSC 1 and OSC 2", p.73). [X-MOD DEPTH] adjusts the depth of the Cross Modulation. As the knob is rotated towards the right, the sound of OSC 1 will become more complex, with more overtones, and will be suitable for creating metallic sounds and sound effects.

* If OSC 1 [WAVEFORM] is set to SUPER SAW or NOISE, the Cross Modulation effect can not be obtained.
* If the Cross Modulation effect is difficult to hear, rotate OSC COmmon (OSC BALANCE) towards the left (the OSC 1 position).

*** Additional Note #19 ***

Judging by the description, cross modulation seems to be identical to frequency modulation. I think the term is used in the analog world to describe the analog equivalent of FM (patching the output of a VCO to modulate the frequency of another VVVCO).

** Tonal changes using Cross Modulation

leave [X-MOD DEPTH] raised, and move OSC2 [RANGE] or [FINE/WIDE] to modify the tone in various ways without changing the pitch.

[LFO 1 & ENV DESTINATION] (LFO 1 & Envelope Destination)

Select one of the following three possibilities to specify how LFO 1 (p.77) and the envelope generator will be applied.

OSC 1+2 (Oscillators 1+2)):

LFO 1 and envelope will be applied to the pitch of OSC 1 and OSc 2.

OSC 2 (Oscillator 2):

LFO 1 and the envelope will be applied to the pitch of OSC 2.

X-MOD (Cross Modulation ):

LFO 1 ande the envelope will be applied to Cross Modulation Depth.

[LFO 1 DEPTH]

Specify the depth for when LFO 1 (p.77) is applied to the pitch. As the knob is rotated from the center position towards the right, the change will become greater. As it is rotated from the center towards the left, the LFo 1 waveform will be inverted, and the change will become greater in the opposite direction. When the knob is in the center position, LFO 1 will not affect the pitch.

*** Additional Note #20 ***

I prefer the word positive or negative modulation when it comes to LFOs to Roland's rather cryptic way of saying things.
The minimum and maximum LFO depths of -64 and +63 seem to correspond to a range of four octaves. The modulation extends to both positive and negative directions. If you have, for instance, a square LFO modulating the pitch with the depth value of +63, you get periodically notes two octaves above and below the normal pitch.


1.4.2. PITCH ENVELOPE Section
-----------------------------

[DEPTH] (Envelope Depth)

Specify the depth of the pitch envelope. Raising the slider above the center position wil produce a greater change, lowering the slider below the center position will invert the shape of the envelope, and produce an increasing amount of change in the opposite direction. When the slider is in the center position, the pitch envelope will not affect the pitch.

When applying a positive (+) envelope to Cross MMMMModulation, the effect will be more apparent if [X-MOD DEPTH] is set to a low setting. When applying a negative (-)
 envelope, the effect will be more apparent if X-MOD DEPTH is set to a high setting.


*** Additional Note #21 ***

The amount of pitch modulation is about two octaves when the depth is set at either the min or the max value (-64 or +63). With a little experimenting you should be able to find most of the other musical intervals as well.

*** Additional Note #22 ***

If you set the amount of cross modulation close to the maximum and try to change the amount with a positive envelope, you don't get that much modulation as mentioned just above these notes. This is because on the JP (unlike on the MS-2000) you cannot go above the maximum limit of a parameter by modulating it. So what happens is that the parameter is clipped to the maximum value for some time. similar effects occur also in pulse width modulation and in other kinds of modulations as well when you are trying to exceed the limits.


[A] (Attack Time ) / [D] (Decay Time]

Specify the Attack Time and Decay Time of the pitch envelope. The value will increase as raised.

A: The time from when the key is pressed until the maximum pitch change is reached.
D: The time from when maximum pitch change is reached until normal pitch is reached.

*** Additional Note #23 ***

The AD(Attack, Decay) envelope looks in a way a bit like a triangle wave.



1.5. Modifying the Brightness
-----------------------------

Sound consists of partials (overtones) at many frequencies. The filter allows a specific range of frequencies to pass (or restricts the way that they pass), thereby modifying the brightness of the sound. The FILTTER section and the FILTER ENVELOPE section allows you to select the Type of this filter, and to make the output waveform change in various ways to modify the brightness.

1.5.1. FILTER Section
------------------------

[TYPE] (Filter Type)

Select one of the following three filter types.

HPF (High Pass Filter):

This type of filter allows partials higher than the cutoff frequency to pass. This is useful when you want the sound to be bright and sharp.

BPF (Band Pass Filter):

This type of filter allows partials in the region of cutoff frequency to pass. This will emphasize the mid-range, and is suitable for creating sounds with a unique character.

LPF (Low Pass Filter):

This type of filter allows partials lower than the cutoff frequency to pass. This is the most common type of filter, and is useful when you want to make the sound more mellow.

[-12dB/-24dB] (CCCCutoff Slope)

This selects the slope of the filter. When the indicator is dark the slope will be more gradual (-12 dB/oct). When [-12dB/-24dB] is pressed to make the indicator light, the filter will have a steep slope (-24 dB/oct). making a clearer distinction between the owertones which pass through and those which do not.


*** Additional Note #24 ***

The character of the two filter slopes is pretty different. The 4 pole (-24 dB/oct) filter sounds a bit warmer to me and starts resonating audibly a lot earlier. The -12 dB/oct filter on the other hand doesn't cut that much content and is also useful at times particularly with highpass and bandpasss filters.


[CUTOFF FREQ] (Cutoff Frequency)

This sets the cutoff frequency of the filter. Cutoff frequency is the parameter which specifies the frequencies at which the filter will begin restricting (cutting off) the partials. By modifying the cutoff frequency you can control the brightness of the sound. As the slider is raised, the cutoff frequency will become higher, producing a brighter tone.


**Filter Type and Cutoff Frequency

When the filter is set to HPF, raising the cutoff frequency will decrease the lower partials, making the sound brighter. At the same time, the volume will also decrease. With high settings of this parameter, some waveforms may produce no sound at all.

When the filter is set to BPF, only the partials in the frequency range specified by the cutoff frequency will be allowed to pass. With high settings of this parameter, some waveforms may produce no sound at all.

When the filter is set to LPF, lowering the cutoff frequency will decrease the upper partials, making the sound more mellow. At the same time, the volume will also decrease.

[KEY FOLLOW]

This sets the Key Follow depth for the filter. When the filter is a LPF, a central setting of Kkey Follow will cause the cutoff frequency to remain fixed, and unaffected by the pitch of the sound (i.e., the note that you played). This means that as you play higher notes, there will be fewer partials in the sound, making it increasingly more mellow in comparison to lower notes. as the knob is rotated toward the right, higher notes will have a correspondingly higher cutoff frequency, allowing higher notes to remain brighter. Key follow to +32 (set while viewing the value in Edit Scope, p.64), the sound will be the same for all keys.  COnveniently, when the knob is rotated toward the left of center, playing higher notes will cause the cutoff frequency to become lower, meaning that high notes will be even more mellow than when the knob is in the center position.

For both HPF and BPF, setting the Key FOllow to +32 will allow you to play all notes with the same brightness.

* When [CUTOFF FREQ] is set to the center position, the key Follow effect will be clearly noticeable.

*** Additional Note #25 ***

Here's a quick intro to the editing scopes on the 8080. By pressing edit and then bank 8 you see the temporary scope which you can use for finding out the value of a control by rotating that control as well as changing the values by using inc and dec. Pressing bank 8 again while in temporary scope changes to edit scope, which is similar to temporary scope the only difference being that the values are changed when you pick a knob for viewing the value. Pressing either velocity or control assign and then picking a knob for editing and changing it's value, you can control how the JP responds to control up/down messages (set in MIDi Options) and velocity. Almost every patch parameter can respond to velocity and/or to a custom controller.


** Ways to use Key FOllow

If you are playing a brass-type sound for a solo, you might rotate KEY FOLLOW[] to the left of center so that high notes will be more mellow. If you are playing the brass sound as a backing part, you might rotate [KEY FOLLOW] to the right of center so that the tone will remain flat.

*** Additional Note #26 ***

If both key follow and portamento are turned on, portamento will affect cutoff as well by smoothly changing it between the actual notes. However, pitch modulation by the LFOs or the envelope will have no effect on cutoff frequency.


[LFO 1 DEPTh]

When LFO 1 (p.77) is applied to cutoff frequency, this parameter determines the depth of the effect. As the knob is rotated to the right of center, the effect will increase. As the knob is rotated to the left of center, the LFO 1 waveform will be inverted, and the effect will increase. With a setting in the center position, LFO 1 will not affect the cutoff frequency (brightness).

*** Additional Note #27 ***

Inverting a square LFO has no practical effect as one side of the square modulates positively and the other negatively and the waveform is symmetric.

1.5.2. FILTER ENVELOPE Section
------------------------------


[DEPTH] (Envelope Depth)

This adjusts the depth of the filter envelope. As the slider is raised above the center position, the change will increase. As the slider is lowered below the center position, the change will increase in the opposite direction. With a setting in the center position, the filter envelope will not affect the brightness.

* Please note the following caution when Individual Trigger (p.116) or External Trigger (p.121) is turned ON. If the Trigger Destination is iether FILTER or FILTEr&AMP, playing without receiving a trigger may not produce the intended sound, since the filter envelope effect will not apply.

* When aplying a positive (+) envelope the effect will be more apparent if [CUTOFF FREQ] is set to a low setting. When applying a negative (-) envelope, the effect will be more apparent if [CCCUTOFF FREQ] is set to a high setting.

*** Additional Note #28 ***

The same talk about parameter limits (Note #22) is also valid in this case.


[A] (Attack Time) / [D] (Decay Time) / [S] (Sustain Level) / [R] (Release Time )

These parameters set the Attack Time, Decay Time, Sustain Level, and Release Time of the filter envelope. Raising a slider will increase the corresponding value.

A: The time from when the note is played until the maximum brightness is reached.
D: The time until the brightness reaches a steady level
S: The level at which the brightness will remain steady.
R: The time from when the note is released until the sound disappears.

*** Additional Note #29 ***

The filter settings are set up very poorly in the initialization patch of the 8080. First the filter envelope depth is at maximum and all envelope times are at zero resulting in nasty clicking. the clicking is part of the sound and may be desirable when doing organ sounds. Generally speaking, however, you want to get rid of the clicks by increasing the envelope times. Another thing bugging me is that neither velocity response to amplitude nor filter key follow = 32 is preset.


1.6. Modifying the Volume
--------------------.....

The parameters of the AMP (Amplifier) section and the Amplifier Envelope) section modify the volume, and how the sound begins and ends.

1.6.1. AMP (Amplifier) Section
------------------------------


[LEVEL]

Specify the volume of the Patch. The volume will increase as the knob is rotated towards the right.
The [LEVEL] settting is saved in a Patch. So if you want each Patch to have a different volume, you can set each patch accordinly. In contrast, the VOLUME [LEVEl] is used to adjust the volume of the entire JP-8080.

[PAN] (Auto Pan/Manual Pan Switch)

Select one of the ways in which the volume or pan (stereo position) will change.

OFF (dark):

LFO 1 (p.77) will cyclically modulate the volume.

AUTO (Auto Pan):

LLLLFO 1 will cyclically shift the panning between left and right.

MANUAL (Manual Pan):

ADjust (LFO1 DEPTH) to pan the sound to left or right.

* the LFo 1 Fade Time setting has no effect on Auto PAn.
* In the following cases the Auto Pan and Manual Pan effects wil be unavailable.
  * When the sound is being sent from the Output jack in MONO.
  * When Output Assign (p.115) is set to PARALLEL OUT.


[LFO 1 Depth]

When [PAN] is OFF (dark) or set to AUTO, this parameter determines how greatly LFo 1 (p.77) will be applied to Level or Pan. Rotating the knob toward the right of center will pproduce greater change. Rotating the knob toward the left of center will invert the LFO 1 waveform, and produce greater change in opposite direction. With a center setting, LFO 1 will not affect level or pan.
When [PAN] is set to MANUAL, rotating the knob toward the right of center will pan the sound toward the right, and rotating it toward the left of center will pan the sound toward the left. With a central setting, the sound will be heard from the center.

1.6.2. AMP ENVELOPE (Amplitude Envelope)
---------------------------------

<snip>

*** Additional Note #30 ***

The controls for the amplitude envelope are identical to the filter envelope except that there is no depth control (the depth is always at the max value and positive you could say). so I've skipped the merely identical descriptions of the envelope phases. If you need a description, re-read the passage about the filter envelope (1.5.2.) substituting filter with amplitude and brightness with volume.

*** Additional Note #31 ***

The amplitude envelope is poorly set up in the initialization patch. The attack, decay and release are set to zero (sustain is at max) which makes the patch easily click (sometimes even desirable). To overcome this, slightly lengthen some of the envelope phases.


** Examples of different envelopes

The following two Patches of the JP-8080 contain typical amplifier envelope settings.  If you wish to create a decay-type sound like that of a piano, or a sustain-type sound like that of an organ, an easy way to do so is to select one of the following patches and adjust the sliders and knobs to your liking.

P1:B87: Decay-type envelope
P1:B88: Sustain-type envelope


1.7. Modifying the Sound (LFO 1)
--------------------------------

*** Additional Note #32 ***

For some curious reason, information on LFO 2 can be found in an entirely different chapter in the original user's guide. So for info on LFO 2, jump to ??? .


The LFO 1 (Low Frequency Oscillator) section outputs a waveform, just as the OSC 1 and OSc 2 sections. However while the OSc 1 and Osc 2 waveforms are used to produce the sound itself, the LFO 1 waveform is used to cyclically modulate the pitch, brightness, or volume of the sound.

* The depth of LFO 1 for each of these is set by the [LFO 1 DEPTh]] knobs on the OSC COMMON section , FILTER section and AMP section.

[WAVEFORM]

Selects one of the following four choices as the LLLFo 1 output waveform The sound will be modulated in the way indicated by the selected LFO 1 waveform.

[Triangle wave)]:

This sound will be modulated continuously. This waveform is suitable for vibrato effects etc.

[Sawtooth Wave]:

When the sound reaches its minimum setting, it will then return to the maximum, and then begin to fall again. If the [LFO 1 DEPTH] in the OSC COMMON, FILTER, and AMP sections is rotated to the left of center, the direction will be inverted. (When the sound reaches its maximum setting, it will return to the minimum and then begin to rise again.)

[Square wave]:

The sound will alternate between two settings.

[Sample  and hold]:

The sound will switch randomly between various settings.

*** Additional Note #33 ***

It is not possible to determine whether the LFOs are synchronized (reset by note on events). There's no sine or smoothed sample andd hold waveforms either.


[RATE]

This sets the modulation speed for LFO 1. As the knob is rotated to the right, the modulation speed will increase.

* the LFO 1 Rate can be synchronized to the MIDi Clock messages of a sequencer, etc. For details refer to "Synchronizing LFO 1 Rate to the Tempo (LFO Sync)" (p.120, and "Synchronizing Chorus, Delay LFO 1, Ensemble or Voice Modulator Delay" (p.144).

*** Additional Note #34 ***

IF you set the rate close to it's maximum value, the LFO switches to an extra rapid setting. I don't know about the frequency, it's not at the audio range but certainly faster than all the othre settings available, I'd guess 10 Hz.



[FADE] Fade Time

Specify the time from when you press a key and the LFO 1 begins to apply until the modulation reaches the amount specified by the Depth settings of each section. Rotating the knob toward the right will lengthen the time until the full amount of modulation is reached.

*** Additional Note #35 ***

The fade effect is very similar to patching an ADSR-envelope (decay and release to zero, sustain to max and attack varies) to control LFo 1 amount for each of the destinations.


1.8. Making Effect Settings (Effects)
-------------------------------------

1.8.1. Adjusting the High and Low TOne (Tone Control)
-----------------------------------------------------

The TONE CONTROL lets you emphasize or attenuate the low or high range of the sound to adjust the tone to your preference.

[BASS]

This knob emphasizes / attenuates the low frequency range. Rotating the knob toward the right of center will emphasize the low frequency range, producing a more solid sound. Rotating it toward the left of center will attenuate the low frequency range.

(TREBLE)

This knob emphasizes / attenuates the high frequency range. Rotating the knob toward the right of center will emphasize the high frequency range, producing a more crisp sound. Rotating it toward the left of center will attenuate the high frequency range.


*** Additional Note #36 ***

I've found that the tone controls are crutial for making some of those "phat" sounds unlike on some real analog and hybrid synths, which I'm not going to mention here.


1.8.2. Adding Spaciousness and Depth to the Sound (Multi Effect Level)
----------------------------------------------------------------------

Multi Effect Level is a function that adds spaciousness and depth to the sound. You can also select the type of multi effect in the [PATCH] (BANK [4]) setting in the lower line of the display.

[MULTI-FX LEVEL ] (Multi Effect LEVEL)

Specify the amount of the multi effects. As the knob is rotated toward the right, effect will be applied more heavily.


1.8.2.1. Changing the Type of Multi Effect (Multi Effect Type)
--------------------------------------------------------------

The type of multi effect can be changed as appropriate for the sound or song that you are playing. the JP-8080 provides 13 types of multi effects.

SUPER CHORUS SLW: Slow chorus with deep modulation.
Super CHORUS MID: Chorus with medium modulation.
SUPER CHORUS FST: Fast chorus with shallow modulation.
SUPER CHORUS CLR: Chorus with a transparent feeling more chorus willl be applied to the high range, producing a light sensation.
FLANGER SLOW: Flanger with delayed modulation.
FLANGER DEEP: Flanger with deep modulation.
FLANGER FAST: FLanger with fast modulation.
DEEP Phasing SLW: Slow phasing with deep modulation.
JET PHASING: an effect reminicent of a jet airplane taking off and landing.
TWISTING: an effect as though the sound were being twisted.
FREEZE PHASE 1/2: A short delay, this is effective in adding a metallic resonance.
DISTORTION: This effect distorts the sound.


*** Additional Note #37 ***

It's faking to say that there are 13 different effects. It all comes down to different presets of a modulation delay effect except maybe the distortion. The effect algorithms are presets and cannot be changed in any way excep the delay and EQ (you can set the amounts for lows and highs).


*** Additional Note #38 ***

As for the quality the delay is great (it even includes stereo panning and gradual lowpass filtering with higher feedback values) and chorus is OK. Flanging doesn't sound too good, the phaser is the worst I've ever heard and distortion has only some limited use. You can get some usable sounds out of it by applying the effect very little or alternatively keeping the patch volume low.


<snip>

*** Additional Note #39 ***

I've ripped the step by step procedure for changing effects as there's not really anything special about it. The effect type can be set per patch and it is found at the patch category (press edit, then bank for). Repetitivley press bank for to get to the effect type, then just use inc and dec to select and exit when you are done. That's it in brief.

1.8.3. Adjusting the Echo effect (Delay)
----------------------------------------

Delay is an effect that adds echoes to the sound. The setings of the DELAy section affect how the delay sound is heard. You can also select the type of delay in the [PATCH](BANK[4]) setting in the lower line of the display.

[LEVEL]

Specify the amount of delay sound relative to the original (undelayed) sound. As the knob is rotated toward the right, the delay sound will become louder.

[TIME]

Specify the time (interval between delays) from when a key is pressed to play a sound until when the delayed sound is heard. as the knob is rotated toward the right, the time will become longer.

<snipped the step-by-step procedure>

[FEEDBACK]

Specify the amount of feedback for the delayed sound; i.e., the way in which the delayed sounds will gradually diminish over time. With small amounts of feedback, the delayed sound will diminish quickly after you release the key. As the knob is rotated toward the right, the feedback will increase, and the delayed sounds will diminish over a longer interval after you release the key.

** Changing the type of delay (Delay Type)

The type of delay can be changed as appropriate for the sound or song that you are playing. The JP-8080 provides 5 types of delay.

PANNING L->R: The delayed sound is assigned to left and right in the order of left -> right.

*** Additional Note #40 ***

In other words, every other delay goes to the left channel.


*** Additional Note #41 ***

The delay algorithm is prety interesting. Firstly there's the gradual lowpass filtering of higher frequencies which seems to be dependent on the feedback setting. Secondly the separation of the two delay lines for the left and right channel is a bit fuzzy meaning that you can hear the sound rapidly moving from the left speaker to the right and vice versa. Also when you pan the signal source around, it affects the balance between the channels. It seems that the pan also works as a cross-fading control between the two channels. Panning hard right, will cause the left channel to become fully silent to give one example. Panning slightly right will cause slightly stronger output on the right channel compared to the left.

PANNING R->L: The delayed sound is assigned to left and right to the order of right -> left.
PANNING SHORTTT: The delayed sound is assigned to left and right in the order of right -> left. The delay time is 1/4 of PANNING L->R/R->L.
MONO SHORT: The delayed sound is assigned to the center. The delay time is the same as PANNING SHORT.
MONO LONG: The delayed sound is assigned to the center. The delay time is twice that of PANNING L->R/R->L.

* The delay time will differ depending on the delay type. When [TIME] is rotated fully toward the right, the delay time for each delay type will be as follows.

MONO LONG=1250 ms (1.25 SECONDS)
PANNING L->R/R->L=625 ms
PANNING SHORT, MONO SHORT=155 ms

* In the following cases, the panning delay effect cannot be obtained.
  * When the sound is being sent from the Output jacks in MONO.
  * When Output Assign (p.115) is set to PARALLEL OUT.

<snipped the "standard" step by step procedure>

** Effect connections

The effects (Tone Control, Delay, Multi Effects) of the JP-8080 are connected as follows.

TONE CONTROL -> DELAY -> MULTI EFFECTS -> PAN -> OUT L/R

*** Additional Note #42 ***

I took the liberty of converting the graphical block diagram originally present to ASCII form.



2. Taking Advantage of the Performance  Functions
===========================================================

<snip, snip, snip, ....>

*** Additional Note #43 ***

I'm only going to include some extracts of this chapter directly related to editing the sound. I only copied the once I feel are the most important and may not be self-explanatory. in fact, I think most of the info I did include would have been better at home in chapter 3.


2.1. Playing Single Notes (Solo Switch)
---------------------------------------

When using a solo instrument sound or when playing single-note solos, it is convenient to select Mono, Legato or Unison so that even if two keys are pressed simultaneously, notes will not overlap or be blurred.
MOno / Legato / Unison can be set independently for each patch,

MONO:

NOtes will be articulated individually and clearly. If you combine this setting with Portamento, your playing will be smoothed.

LEGATO:

NOtes will sound one at a time, and will be joined smoothly to the next note only when you play legato (i.e., pressing the next key before releasing the previous key).

UNISON:

All voices will sound together. The number of voices which can be sounded simultaneously when the Key Mode is Dual or Split wil be according to the Voice Assign settings. (p.116) If both [LEGATO] and [UNISON]) are pressed together, notes will be sounded in Legato Unison.  You can also skew the pitches of the voices to create thick sounds (Unison Detune)

* When all button indicators for Solo Switch are dark, the JP-8080 is in Polyphonic mode (normal playing condition).

*** Additional Note #44 ***

The actual program code on the JP-80x0 synths seems to be heavily optimized. Some times when layering two complex patches and using up all the polyphony (5 notes when layering) having lots of rapid modulation going on or when using Unison, I've sometimes noticed the LFO rates slowing down. In addition, modulating the filter cutoff is at times clearly more stepped and slower, in stead of smoothly gliding, only few "gigantic" and slow changes in cutoff are heard. The situation is particularly bad when Unison is on and you are trying to modulate a control-assigned parameter via MIDI. In that case, you'll always here the cutoff and other modulation heavily quantized and slow but if you grab the physical cutoff control for instance while unison is on, no such stepping occurs. This lead me to suspecting a bug in the first place but unfortunately there's no poit in complaining to Roland because the 80x0 synths ar discontinued. By the way, I'm running the latest Os 1.04 which is the last update for the 8080.

<snipped the step by step procedure for SOlo Switch>

* When Mono or Legato are used, the sound may appear lower in volume than when you play polyphonically. In this case increase the Patch Gain (p.121).
* If you select FEEDBACK OSC for the WAVEFORM of OSC 1, [MONO] or [LEGATO] will automatically be turned on. It is not possible to turn this off, nor will be possible to turn [UNISON] on.

*** Additional Note #45 ***

The Unison depth can be adjusted in semitone steps (0-50) in the patch menu. In that menu, as well. lies the Patch gain setting which allows you to boost quite patches either +6 or +12 dB. Be careful, though, this leads to clipping as do heavily resonant sounds when played polyphonically and patch volume is at the maximum (to remedy this lower the patch volume). Unison causes often clipping, too.

*** Additional Note #46 ***

Here's in practical synth terms what the rather cryptic descriptions above are trying to say

Mono:
-The envelopes are always re-triggered when new notes arrive.
-Portamento is always active.
-The counter for LFO 1 fade is reset whenever a new note on event arrives.

LEGATO:
Legato is detected when a new note on message arrives before the note off message for the previous note.

Supposing legato is detected:
-LFO 1 fade counter is not reset
-Envelopes are not re-trigger
-Portamento is active

But when ever there's a note that is not played in legato (breaking out of the legato state) the opposite happens:
-LFO 1 fade counter is reset
-Envelopes are re-triggered
-Portamento is not active meaning that the new note wil instantly jump to the destination pitch (no portamento)

2.2. Playing Analog Synthesizer-like Solos (Envelope Type in Solo)
------------------------------------------------------------------

Analog synthesizers have the characteristic that when key is newly pressed , the sound does not begin from zero, but continues sounding from the continuation of the envelope of the previous sound.  The JP-8080 can simulate this characteristic to add an analog synthesizer-like feel to solos that are played using mono/legato/unison.

STANDARD:

The note will begin sounding from the envelope zero.

ANALOG:

The note will begin by continuing the envelope of the previous note .

The Envelope Type in Solo setting can be set independently for each patch.

<snipped the step by step procedure>

*** Additional Note #47 ***

The setting can be found in the patch menu. The analog envelope emulation setting is very flexible. It works for all three envelopes in both mono, legato and unison modes.

<snip>

2.3. Adding Cyclic Changes (Modulation (LFO 2))
-----------------------------------------------

Chapter 3 explained how to use LFO 1 to cyclically modulate the sound, but you can also use the modulation lever of a MIDI Keyboard to apply modulation from LFO 2 at a different frequency than LFO 1. Since the sound will be affected only when you move the modulation lever, this is a useful way to add accents to your performance.

The LFO 2 waveform is triangle wave. When the modulation lever is moved, the pitch, brightness and volume will be modified simultaneously, each according to the Rate and the various Depth settings that you have made.

Lfo 2 settings are made independently for each Patch.

* Part(s) which can be controlled * When connected to REMOTE KBD IN
The part(s) which will be controlled will depend on the Key mode.

Single, Split: The effect will apply to the Patch of the Part selected by Panel Select.
Dual: Regardless of the Panel Select setting, the effect will apply to the Patches of both Parts. If you wish to apply an effect only to the Patch of one or the other Part, you can erase the control assign settings of the other Patch.

*** Additional Note #48 ***

Or simply set the LFo 2 Amp, LFo 2 Filter and LFO 2 pitch settings to zero for one of the parts.

* When conected to MIDi IN
The patch of the part which is set to the same channel as the transmit channel of the external MIDI device will be controlled. (Part MIDi Channel: p.118)

*** Additional Note #49 ***

In other words, when controlling the JP from a sequencer (as you would normally do as keyboard input is usually echoed through the sequencer), the MIDI channel of controller 01 events wil determine the destination part of the modulation wheel events. You can set the MIDI channels for the parts in the part-specific menu (on the 8080 press bank number 3 repeatedly after pressing edit to find the MIDi channel parameter). You can change the part whose settings are to be edited by changing the part selection while you are in the part menu.

[DEPTH SELECT]

Press [DEPTH SELECT] to select one of the following three objects for which you will set the depth of modulation.

PITCH: Set the depth of the LFO 2 effect to pitch. This produces vibrato.
FILTER: Set the depth of the LFO 2 effect on the filter (brightness). This produces a wah effect.
AMP (amplifier): Set the depth of the LFo 2 effect on the amplifier (volume). This produces tremolo.

[DEPTH]

Rotate [DEPTH] to set the depth of LFo 2 effect on the currently selected item [PITCH, FILTEr, or AMP).
Rotating the knob to the right of center will produce a greater effect. Rotating the knob to the left of center will invert the LFO 2 waveform and produce a greater effect. With a setting of center, LFo 2 will not effect the sound.

[RATE]

Rotate [RATE] to set the speed of modulation for LFO 2. Rotating the knob toward the right will produce faster modulation. The rate setting is common to PITCH, FILTER, and AMP. These cannot be set separately.


*** Additional Note #50 ***

As you are, in fact, controlling only one LFO but you can modulate the amplitude of the LFO for pitch, filter and amplitude separately.

*** Additional Note #51 ***

I've found the easiest way of editing the LFo 2 settings is to display them on the edit scope. You'll be able to view the parameter value in real time as well as being able to use inc and dec as well as (hold inc and then decc or hold dec and then inc for rapid changes). For more info on the edit scoe, please see Note #25.


*** Additional Note #52 ***

The frequency range of LFO 2 differs significantly from LFo 1 suggesting that it's aimed for producing conventional musical effects. The lowest rate setting of zero is a lot faster than that of LFo 1 which means that you can set the frequency of LFO 2 more precisely. Note that LFo 2 will also have an ultra fast rate setting (about 10 Hz I think) which is activated when you rotate the speed knob all the way to the right.


2.4. Smoothly Changing the Pitch between Notes (Portamento)
-----------------------------------------------------------

Portamento is a function that smoothly changes the pitch from the first-played note to the pitch of the next-played note. It is effective to use Portamento when playing in Mono mode .
Portamento settings can be made independently for each Patch.

[ON] (Portamento Switch)

Each time you press [ON], the Portamento effect will be turned on/off. When it is on the indicator will light, and the pitch of the sound will change smoothly, similarly to the way in which notes on a string instrument such as a violin can be shifted smoothly by sliding the finger which is pressing the string along the fingerboard without releasing the string. This effect is specially effective when playing sounds such as whistle or trumbone.

[TIME]

Rotate [TIME] to set the time over which the pitch will change (Portamento Time). As the knob is rotated toward the right, the Portamento Time will become longer, and the pitch change will be slower.


*** Additional Note #53 ***

You can vary the portamento time in real time and the rate of change will change even while gliding from one note to another. If the pitch is gliding from one note to another, you can turn portamento off resulting in the pitch instantly jumping to the destination note. Some times portamento is also called glide.


*** Additional Note #54 ***

On the JP-80x0 synths the portamento is a linear constant-time variation. Linear means that the frequency change is a straight line provided that frequency is on the logarithmic vertical axis and time is on the horizontal axis. Other not so common variations include exponential (the gliding rate accelerates when moving toward the destination note) and logarithmic (the gliding note decelerates towards the target note) portamentos. As you might expect, the pitch graphs resemble exponential and logarithmic functions respectively if graphed in the above-mentioned coordinate system.

Constant-time means that the time it takes to glide from one note to another is a constant. In order to keep this time constant, the gliding rate must be adjusted at the beginning of every glide. The adjustment made to the gliding rate depends on the interval between the notes, the larger the interval, the faster the glide has to be. Constant-time portamento is used on some other Roland synths, too, namely the TB-303.

The other, actually more common, type of portamento is constant-rate portamento. The gliding rate remains constant all the time, in other words, the interval between the source and destination notes doesn't affect the gliding rate at all. The result is that it takes longer to glide larger intervals. In the case of a linear constant-rate portamento gliding two octtaves takes twice the time of gliding only one.

By using Cakewalk's CAl scripts or by writing a MIDI FX plug-in it might be possible to approximate constant-rate portamento as well as logarithmic and exponential glides on the JP-8080. This would however, require some serious mapping and real-time remote tweaking of the portamento knob while a glide is going on but it should be possible at least theoretically speaking, although I'd guess that the 128 step range of portamento values somewhat limits the real-world results you can get.



3. Credits
===========

The Owner's Manual of the JP-8080 copyrighted by Roland provided all the information in chapters 1 and 2 (chapters 3 and for of the manual). So thanks to roland for writing the user's guide.
All additional notes and the typing work by
Veli-Pekka Ttil (vtatila@mail.student.oulu.fi)
http://www.student.oulu.fi/~vtatila
For more JP-8080 information, visit:
http://www.student.oulu.fi/~vtatila/jp_tips.html


Thanks for reading till the end and I hope this information helped you on the way to killer patches.


