How to Use C700: Sampler Features Pt. 2

C700 Sampler Right Side

Now let's look at the right side of the sampler, where we get to control several effects that shape the sound of the selected sample. We have volume control, several effect toggles, and a slightly unusual but intuitive ADSR envelope (which we'll cover on the next page).

These effects apply to the selected sample, meaning that if you assign this sample to multiple channels, the same settings will be recalled, and if they are changed, the change will occur in all cases. (Protip: You can avoid this behavior by using MIDI CCs to control the parameters instead, but in most cases this interface will be sufficient and easier to use. Use MIDI CCs if you wish to automate any of these parameters, i.e. change them mid-song.)

Sample Volume

The Volume knobs are a "master volume" setting for your selected sample. You can control the left (L) and right (R) stereo individually. Keep in mind though that only mono samples are supported, so this effect is somewhat limited. Most of the time, these values can be comfortably raised to the maximum of 127. This feature can't be automated; instead use note velocity and channel volume to control how loud your sounds are within the song.

You can set the desired stereo panning for the sample this way by using a higher value for either L or R, but panning can also be controlled on individual MIDI channels, which is a more standard way of handling that effect and also more versatile (for instance, a sample used on two different channels could be panned left in one channel and right in the other).

Effect Toggle: Echo

The Echo toggle enables the SNES's echo delay for this sample. If it is ticked, echo delay will apply to the sample. If disabled, you will hear this sample without any echo.

This effect can also be automated using MIDI CC#91 (Echo Enable), where it will apply to the MIDI channel you assign the CC instead. Using the CC method, a sample could potentially be heard both with and without echo delay at the same time on different channels.

Effect Toggle: PMOD (Pitch Modulation)

The Pitch Modulation (PMOD) toggle enables a cool but chaotic SNES feature for your selected sample! Sort of like FM synthesis, if Pitch Modulation is enabled, the sample will be used to modulate (i.e. change over time) the frequency of another sample currently playing. The result is usually a very distorted tone, but the sound is very distinct and can be used as a wonderful effect. With simple waveforms, a limited 2-operator FM sound is possible!

In C700, the note with PMOD enabled will generally affect the most recently played note before it. This is due to the interaction between C700's dynamic voice allocation (which spreads new notes out across all 8 SPC700 channels) and the actual implementation of pitch modulation on the SPC700 chip, which applies PMOD to the SPC700 channel before the note with PMOD (for example, channel 7 pitch-modulates channel 6).

This bizarre interaction makes Pitch Modulation a bit challenging to reliably trigger using C700; here are some pieces of advice for getting it to work how you want.

  • On the sample (or MIDI channel) you've enabled Pitch Modulation for, it is best to place notes slightly after the note you're trying to pitch modulate, rather than at the same time. The offsetting will more reliably trigger the effect.
  • The effect won't trigger when C700's voice allocation wraps around from channel 8 to channel 1, because SPC700 channel 1 can't modulate anything. There's no way to force C700 to put a specific note on a specific SPC700 channel, so if this is stopping PMOD from triggering where you want it, try putting another note (perhaps at 0 velocity if you don't want to hear it) before the note that should be triggering PMOD but isn't, to offset the channel count.

Pitch Modulation can be toggled on your MIDI channels instead by using MIDI CC#92 (Pitch Modulation).

Here are a few examples of this effect in action:

EXAMPLE 1: A sine wave with a long release envelope (SR2) and Pitch Modulation enabled:

EXAMPLE 2: Pitch Modulation used in a solo (along with some wide vibratos):

EXAMPLE 3: Pitch Modulation and Echo Delay combine to form a guitar amp-like sound:

Effect Toggle: Noise

The Noise toggle will enable Noise mode for the selected sample, a similar hissing effect to the dedicated noise channels of many, many soundchips (like the NES and Gameboy). The SNES's noise output is not particularly robust, but 32 total frequencies are available.

Note that enabling this effect in the C700 interface will lock you out of using the sample instead of noise. You can load a very small "placeholder" sample to avoid taking up much unnecessary space, but (surprisingly) it does not work if there is no sample at all. To avoid this behavior, MIDI CC#93 (Noise On) can be used on a MIDI channel to enable Noise mode for only that channel. The sample will be otherwise unaffected.

Effect Toggle: Mono

The Mono toggle is one of the most useful tools for keeping polyphony under control. Enabling this mode will restrict the selected sample to a polyphony of 1, meaning if an additional note triggers while a note is sounding, the pitch simply shifts to the new note's pitch, and the channel never hits a higher polyphony count. The new note does not trigger a fresh ADSR envelope, so this also offers a unique sound characteristic reminiscent of many synths. New notes will trigger fresh ADSR envelopes if the previous note has already been released, and the old envelope will cut off.

Turning this on is highly recommended for any sample that won't require more than one note at a time, such as a lead, bass, or drum. It is also helpful if you are using release envelopes (SR2), which can easily trigger extra polyphony otherwise.

Mono mode is controllable with MIDI CC#126 (Mono Mode On) or MIDI CC#127 (Poly Mode On). I am not certain why two separate CCs exist for this, since they appear to function identically (but in opposite directions). Functionally there does not seem to be a difference. The most recently-set one takes priority.

Note 1: Enabling Mono mode for every sample in your project will disable C700's dynamic voice allocating behavior (where new notes get spread across all 8 channels depending on what's available).

Note 2: Avoid using the same Mono-enabled sample on MIDI channel pairs 1+9, 2+10, … 8+16; if you do, each channel's note will cut the other off. There is some sort of "mirroring" split between MIDI channels 1-8 and 9-16 that causes this behavior under the hood.

Effect Toggle: Glide

Glide is the portamento setting, and also comes with a "Rate" box where a value of 0 (immediate) to 127 (agonizingly slow) can be input. The terms glide and portamento both refer to a pitch slide between notes – when a new note occurs, rather than the new pitch immediately sounding, it is approached with a pitch bend from the previous pitch. It's like scooping into a note when you're singing, or that big clarinet solo in the intro of Rhapsody in Blue. Instead of _ |‾ it looks more like _ /‾.

The Rate value controls the speed of the portamento. At low values, the portamento will occur quite quickly, and at high values, it takes an eternity to land on the new note.

If you want to use portamento only selectively (which is likely), use MIDI CC#65 (Portamento Enable) to enable this feature for a MIDI channel, along with MIDI CC#5 (Portamento Rate) to automate the speed. If you want to choose a specific pitch for the portamento to start from, use MIDI CC#84 (Portamento Control) to select a note – the lower the value, the lower the note.

The Glide effect can be used in conjunction with Mono mode for a very natural "synth solo lead" sound, but it also functions in regular polyphonic mode too. The previous note will keep playing while the new one begins bending upward starting from the last note.