Arpégiateur

Citation : Mini Arp Tutorial

"MIDI-arpish" sound using ALG #9 For something different, I thought I might educate you a little with using the Kurzweil's MIDI Clock functions. The clock sources ACLOCK and BCLOCK used together can yield some awesome and very useful arpeggiator sounds.

In this example, we will be trying to create an analog sounding arp that has resonance.

From experience, I've found using traditional analog sounds to yield the best results. With the additional aid of some of VAST's DSP functions, we can make a thick sound without having to use too many layers.

The first decision to make is the waveform (KEYMAP) we will use. For something along the analog tradition, we will use the K2's SAWTOOTH.

With that in mind, I'll also need to find an ALGORITHM that has a resonance block in it and something that will make the "Sawtooth" KEYMAP a little thicker. So by looking through the manual, I can see that ALG#9 has the SAW+ DSP function along with the LP2RES function.

Lets start on the sound now that we have these key components.

Go to PROGRAM 199 "Default Program" and press EDIT.

Change the KEYMAP to "151 Sawtooth".

Press ALG.
Change the algorithm to no.9.
Make the DSP path as follows:

PITCH -> SAW+ -> SAW+ -> LP2RES -> AMP

The first thing we need to do is get the sound into tune. The two SAW+ blocks we are using are causing the K2 to play a uniform note across the keyboard.

Press F1 PCH.
Change "KeyTrk:" to 100ct/key
Press F2 PCH
Change "KeyTrk:" to 100ct/key

Before we go any further, I'll pass on this little tip for people that don't know. A sound can be filtered to the extreme where no sound can be heard at all. The LOWPASS filters can do this. Its usually called "opening"/"closing" the filter.

By us manipulating the LOWPASS filter, we can achieve the effect of movement within a sound. Our movement we want is in sync with MIDI, so we will be using some of the Kurzweil's MIDI software sources (clocks).


Press F3 RES.
For more control over the filter, we will use the "Src2:" part of LP2RES.

Change "Src2:" to "B Clk2". (This is twice as fast as BCLOCK)
For movement in the "Depth", we will use GPHASE1.
Change "Depth:" to "GPhas1".
(GPHASE 1 is a rising sawtooth waveform in sync with MIDI.)

At this stage, we need to start thinking about how much we want to open/close the LP2RES filter.

As it stands at the moment, the sound is a little dull. So I'll open it up just a little more.

Change "Coarse:" to C5 523Hz.

To close this filter, we will think in octaves.
Setting the "MaxDpt:" to -1200ct will bring the filter down to C4.
Setting the "MaxDpt:" to -2400ct will bring the filter down to C3.
Setting the "MaxDpt:" to -3600ct will bring the filter down to C2.
Setting the "MaxDpt:" to -4800ct will bring the filter down to C1.
Setting the "MaxDpt:" to -6000ct will bring the filter down to C0.

Listen to the sound. (Ignore the distortion for a moment).
Enough fiddling now.
Change the "MaxDpt:" to -5800ct. (Its my preference).

Now we are going to correct the distortion problem we have. This is due to heavy resonance, which might be something you would like in the sound.

Press AMP.
Change "Adjust:" to 0dB
This is a major cut in volume.

Change "VelTrk:" to 10dB.
This is to remove the velocity sensitivity that the sound will have in relation to volume.

Change "KeyTrk:" to -10dB/key.
This is to boost the volume at the bottom end of the keyboard.

At the moment, it's just the filter in sync with MIDI. There is plenty we can still do like manipulating the pitches of the SAW+ blocks and the KEYMAP itself. (via the PITCH page.)

But lets first make the sound a little thicker.
To do this, we must make the SAW+ blocks slightly out of phase with each other.

Press F1 PCH.
Hold down a key and change "FineHz:" to -2.40Hz.

Press F2 PCH.
Change "FineHz:" to -1.10Hz.

Lets get a little more wild now with the pitch of the SAW+ block.

Press F1 PCH.
Change "Src1:" to "AClock".
Using different clocks usually leads to some wild and funky "arp" sounds.

Change "Depth:" to 1200ct.

So this block isn't to overbearing on the sound. We will cut the volume of just this block.

Change "Pad:" to 12dB.

When I'm auditioning a sound like this, I usually play it in octaves. The sound becomes really "meaty".

Also, you will notice that we haven't had to use any EFFECTs at all. If I had something like KDFX, I would be looking at maybe putting it through a CHORUS block.

I'll leave the EFFECT up to you at this stage. But for those who are wondering, I used the "101 Big Kick Room" on my K2000. With a "Wet/Dry Mix:" of 45%.

This sound could be played and utilized at this stage. So press EXIT and SAVE it. But for those wanting more, I'll move onto making it a bit more powerful.

Press DUPLYR.
This has just duplicated what we have done and created 2 LAYERs.
This is indicated at the top right corner. <>Layer: 2/2
So remembering we are in the newly created layer we can move on.

Press OUTPUT.
Move the panning 3 positions to the right.
This is is to spread the sound more.

What we are going to do is make it so the 2nd LAYER is actually brought into affect by the ModWheel.

Change "CrossFade :" from OFF to MWHEEL.
Change "XfadeSense :" from NORM to RVRS (Reverse).

If we left it at NORM (Normal) when the ModWheel moved above the half way position, the sound would go off.

Now to give the sound a different "arp" we will play around with the filter in this LAYER.

Press F3 FREQ.
Change "Src2 :" to "A Clk2".

Move the ModWheel up and play the sound.
Give it a NAME and SAVE it !!!!!!

It gets easier the more you dive into it. I promise ;-)

Hope you enjoyed this one.

Brian Cowell
Copyright 2000