Those mysterious 4 delays on the Prophet 12. I heard Dave Smith in a video saying, in effect, that is all you needed for creating other effects. But how? You’ve come to the right place! Some of this material is discussed in the manual. I want to go a little deeper to see what else can be done.
One key observation- the delays let you do so many things that if used wisely, you can save oscillators for other things. A simple example would be to use delay for chorus instead of adding a second detuned oscillator.
A few tips
- Be sure to pay attention to which of these effects require the Prophet to be in stereo mode or not. Anything modulating the pan settings for the delay filter will require stereo mode.
- The Delay Time setting is exponential. 0 is .9556 msec. 128 is 346.1118. 255 is 1000 msec.
- It is easy to calculate the correct delay setting for a given beat for a given tempo (or just use sync). For example, if the tempo is 100 BPM, quarter notes happen every 600 msec. A delay of 300 msec would add 1/8 note pulses.
- A Feedback setting of 0 produces 1 echo. The spacing between echoes is the Delay Time.
- You hear the echoes better with a short release (30-40) on the envelopes, but with a long release you can get an interesting feedback sound, but it can also distort the output.
- The only way to “turn off” delay is setting the Amount to 0.
- Tuned Feedback (high +/- amounts) plus delay creates very odd sounds.
- Combining the arpeggiator with delay in sync mode (and using max amount) can create very complex rhythms you would have trouble creating otherwise.
Fundamental Delay Controls
Delay Time, Amount, and Feedback are common to delay circuits. The Prophet 12 is stereo capable and has filters so add panning and hi and low pass filters to the delay output.
- Delay Time is the time between echoes. The exact times in milliseconds for each value are in the manual.
- The amount is not a “wet/dry” control- it is just the amount of the delay signal (the “wet”) added to the output.
- Feedback is the number of echoes.
Reverb
You can get reverb with delay with these settings. Set the Delay time ~100. Feedback to 55. Amount to > 80. Everything is related to the tempo you are playing so pay attention to what sounds best for that tempo.
Flanger
This is tricky but a starting point is Delay Time 20, Amount 60, Feedback 60. A filter with a slow, negative envelope enhances it greatly.
Add LFO to the Delay Time with a frequency setting around 12. Since very slow, you want to change the phase to get the effect to start right away. Turn on wave resett (for the LFO) and set to 30. The amount of LFO should be around 30. If using a triangle, you do not need any slew.
You can also modulate the Delay Amount with an auxiliary envelope to really shape things. Using two delays, hard panned left and right (so you need to be in stereo mode) will spice it up. Just change the other settings a bit on each.
Chorus
Chorus is related to flanging – just with a higher delay time to hear the pitch fluctuations that create chorus.
Delay Time setting for chorus needs to be in the 57 – 63 range. That’s where it will start. Feedback of 40 is good (too much and it is not a sweet chorus) and an Amount of 110. The LFO needs to modulate the Delay Time. I like a triangle frequency of 35, amount 8, slew 0.
You can play with where the effect becomes noticeable with the Delay Amount, Time, and LFO settings. Many ways to adjust. And since we are talking about the Prophet 12, you can add detuned oscillators, slop, panning on the delays or the main sound- so many amazing things you can do.
Sample & Hold
You can also create toned pulses very much like applying Sample & Hold to pitch but that sounds very different and really good. You need a smooth LFO, so use triangle or add a lot of slew to the others and modulate the delay time. You should also modulate the LFO amount with a second LFO to get something really interesting. The amount of the effect should be controlled by the mod wheel and/or an auxiliary envelope.
Here is a starting point: Delay Time 68, Amount – variable to taste but 20-30 to hear, and Feedback in the 50’s. For LFO1, use a Triangle with a frequency of 178, amount 18, and slew of 5. Modulate LFO1 amount with LFO2 at a frequency of 115, amount 15, slew 6. The LPF and HPF filters can be used to highlight what tones are coming through.
Experiment! You can also make pulses that create a dual tone effect I call “The Dial Tone From Hell.”
Rhythmic Pulses
The delays can be synced with time and note beat divisions. You can do this with the arpeggiator on or by playing in the tempo of the arpeggiator (but with it off). This is great for creating the illusion of extra notes being played in between what you are playing and creating complex rhythms.
In this example, the tempo was 70BPM but the arpeggiator division was on 8th notes, so a note played every 428 msec. (60/70 / 2). To get a dotted 8th extra note in between these notes you have some choices. You need an odd multiple of 214 msec (half of 428) to make it sound spot on. The math is not hard and will give you many possibilities. Of course, if using the arpeggiator, just hit sync and try out different options.
Part Two
Part Two will go even deeper, once I figure it all out! Here’s a taste.
- doubling
- slapback
- polyrhythms
- phaser
And more! I have only used a single, mono delay in these examples so far. Much more is possible when you add more delays and introduce stereo effects.
Credits
I applied the information from these amazing articles to the Prophet 12.
https://www.soundonsound.com/techniques/digital-delay-tactics
https://mynewmicrophone.com/complete-guide-to-the-flanger-audio-modulation-effect/
Erich Izdepski 