Enchanting Instruments 91 - U-he Filterscape VA Review 10 - Chorus/Delay

Filterscape VA has a standard analog synth configuration, which is unusual for u-he company. This article deals mainly with the common parts of analog synthesizers, so this article can be applied to other synthesizers as well. In this article, I will focus on the chorus, which is often found on synthesizers, and the delay, which is often used on synthesizers.

Order of Connection of Filterscape VA Effects

Filterscape VA has CHORUS and DELAY built in. The effects are processed after exiting the AMP; they are treated as mono until the stage before the AMP, where they are converted into stereo and the stereo signal enters into the CHORUS. The stereo signal then goes into the Delay, through the final output limiter and level, and out to the DAW.

The order in which the effects are connected is CHORUS to DELAY, and this order cannot be changed. Normally, this order doesn’t feel out of place. However, there is a free synth called Podolski, which is cut from u-he's Filterscape VA, and the connection order is from DELAY to CHORUS. This is an uncomfortable order. It sounds crazy when set to extreme settings. I think this is interesting, but it is a strange order. I don't think many guitar players who make full use of effects would connect a chorus after a delay, but what do you think?

CHORUS

Chorus was one of the most popular effects for analog synthesizers. The chorus effect on the 1982 Roland Juno-60 is particularly well known. As the name implies, the chorus effect can be used to create multiple performances and at the same time add a sense of spatial expansion. Above all, the chorus can make even a dull sound sound gorgeous. I often hear comments that it is pleasant to play. Because of this, the chorus has been very popular since that time. In the 80s, BBD devices became available at low cost, and choruses made with analog circuitry were common.

How a Typical Chorus Effect Works

Chorus is an effect that uses delays. For example, if there are three delay circuits, the delay time is set to about 5 to 30 msec, and the extraction position is varied by modulation. The start position is then shifted by 2pi/3 radians and synthesized. There is no feedback in the chorus. If there is feedback, it is a flanger, which is a different effect.

Modulation may not sound very familiar to you, so I have drawn up an image of it as shown below. Although you don't see it very often these days, I think a cassette tape is easy to understand. First, there are two playback heads. The DrySound playback head plays a normal sound. The other playback head, DelayTime, plays a little later than DrySound. This head smoothly moves back and forth between -1 and 1. Its movement speed is back and forth in the range of 0.1 to 10 Hz. The movement uses a sine wave, and the amplitude value is the point of movement.

How does the sound change with this movement of the playback head? When the DelayTime playback head moves in the direction the tape is moving, the speed is slower than the tape's original speed, so the pitch is lower. When the playback head moves in the opposite direction, the speed is faster, so the pitch rises. The pitch that is the same as the Dry sound is at +1 and -1, when the sine wave is derived to the 0 position. In other words, when the playback head is temporarily stopped. With this kind of trick, the pitch goes up or down slightly. The graph below shows three of these DelayTime playback heads, each starting at 0, 2pi/3, and 4pi/3 radians, with the DelayTime position as 0. X is time and Y is the amount of movement of the playback head.

The CHORUS in Filterscape VA has a FEEDBACK parameter that can be used to create a flanger-like effect in addition to the original chorus effect. The CHORUS in Filterscape VA also has a FEEDBACK parameter that can be used to create a flanger-like effect in addition to the original chorus.

Here is a sample of Filterscape VA's CHORUS. For comparison, the first sample is without chorus, and the next sample is with chorus turned on. You can see that the left and right sides of the sound are clearly expanded.

DELAY

Another effect built into Filterscape VA is delay. This effect is so fundamental that it can be said that the foundation of spatial effects lies in delay. The principle delays the incoming sound. If it is mixed with the original sound, an echo effect can be obtained. That's all there is to this effect, but it can be used as a delay to create a variety of effects, and there are countless applications for this effect.

The Filterscape VA delay is a simple one and is just an added bonus. It does not do what the often-used ping-pong delay does. There is no built-in filter, so the sound is clear and repetitive. If you want to make full use of delay, I recommend using an external delay.

The delay time is not absolute time, but is synchronized with the tempo of the DAW. The time can be adjusted from 1/64 to 1/1. It is easy to handle musically, as it is possible to use a dotted point, triplets, etc. Left and right can be handled independently, so it is easy to create a stereo feel. FEEDBACK is the amount of output signal returned to the input. It can be returned to the same channel or to the opposite channel. The only other function is the mix balance between the original sound and the effect sound. The following figure shows the waveform of a single note delayed by 1/4, which is repeated every beat, but the amplitude is reduced.

Here’s a simple sample. The first delay has no delay and it’s turned on immediately after the delay. No chorus is used, so the stereo feel is from the delay.

This concludes the introduction to Filterscape VA. In the next article, I would like to give an overview of Filterscape Q6.

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