could someone gently post a chorus patch?
I'm a new PD user...
hope to receive lots of help by searching around in the forum.

thanks a lot guys

i'll explain it:

a chorus is basically just a series of vibratos, mixed in with the original signal.

to make a vibrato, you need a delayline.

so, your original signal goes to [delwrite~ somename]

then, you read that delayline back at modulated speed to make the vibrato.

we can make a simple modulator using [phasor~] and [cos~]

we also need to scale it a bit as [cos~] outputs from -1 to 1.

so,

[phasor~]
|
[cos~]
|
[+~ 1]
|
[*~ 0.5]

that gives us a nice sine wave oscillator from 0 to 1.

now we need to scale one more time to make the chorus 'depth'. you might want to research with google to find the ideal chorus depths, but i think around 20-50ms is a usual amount.

so:

[phasor~]
|
[cos~]
|
[+~ 1]
|
[*~ 0.5]
|
|
|
|
| [ r depth]
| |
| [*~ 50]
| /
[*~ ]

then, we need to add the delayline reader. vd~ is the object that does that.

[phasor~]
|
[cos~]
|
[+~ 1]
|
[*~ 0.5]
|
|
|
|
| [ r depth]
| |
| [*~ 50]
| /
[*~ ]
|
[vd~ somename]

that's one basic chorus 'voice'. however to be effective, you really want to mix a couple of voices in with the original signal.

see how our [phasor~] goes into the [cos~] object to shape it into a smooth (co)sine wave? well, all we have to do is add a value to the phasor~ output to offset its phase.

let's say we want 2 voices for our chorus, then we just add [+~ 0.5] to the phasor~'s output, and then create another whole chain of objects just as we did for the first voice.
if we want 3 voices, then we can add [+~ 0.33] and [+~ 0.66] respectively to two other voice chains...and so on

finally, sending a value to the inlet of the base phasor~ gives us our speed control.

then we can just connect all the resulting voice signals and mix with the original input signal, and that's about it for a simple chorus.

thanks a lot for you kind a quick response... in a few days I try to build up this chorusy patch and see what happen. Now I'm working on a patch made of squared and triangular wave for the Conservatory. Hope o have time to make my own patches.

Thanks a lot

here we are... I'm very impatient.
So, maybe something is wrong but I'm sure somebody could fix it in a while.

1. Don't know how to mix the 4 signals in one (the dry line and the 3 wet line).

2. Don't know how to build a dry line for the voice to get from the acd~ to the dac~ without any processing.

Let me know.

http://www.pdpatchrepo.info/hurleur/simple_chorus.pd

actually, it works fine without mixing in the dry signal.

that patch of yours would never have worked how it was for a couple of reasons:

1. your delayline [delwrite~ CHORUS] had no length specified. It needs to be [delwrite~ CHORUS 10000] or something like that, depending on how long you'd like the delayline (and how much warble you want in the chorus)

2. your [phasor~] objects have no value input to them, so they just sit there doing nothing.

3. there was no actual controller for 'depth'

see attached (working) version.

you can right click on those depth and speed sliders to see the sort of range they have been set at.

also, there is a basic phasor~ sequence being run to test, but obviously replace that with your adc~ object if you need to take external input.

http://www.pdpatchrepo.info/hurleur/simpleChorusEDIT.pd

oh, and a tiny little side note:
always better to make your pd patch filenames all one word. instead of "simple chorus.pd" you should use "simple_chorus.pd" or "SimpleChorus.pd" or something like that. It makes things a lot easier later on when you want to embed patches in other patches as abstractions, and stuff like that.

thanks a lot I'm learning a lot. I wouldn't like to bother you so I take a few days to improve the patch and eventually I'll post it with a single word name as you suggested me

Maybe I'm running too much, I have to get back to puredata example patches and figure out simple things first. I'm ready and willing.

Thanks again.

Sorry for the delayed reply, I don't check the forum very often.

I've made a few chorus abstractions, some emulating "classic" designs. I think there are a few finer points that are often missed.

First, it's more useful to have the modulation depth adjustable in cents rather than in ms, but this takes some work to implement. The amount of detuning is proportional to the derivative of the modulation waveform. So a triangle wave modulator will result in perceived square wave pitch modulation. But this isn't symmetric. A falling slope will detune more strongly than a rising slope. It doesn't make a big difference for mild detuning, but it's important to consider if you want to make trill effects. If you want symmetric modulation, you can distort the shape of the modulator waveform.

Second, there are a variety of "classic" effects in addition to the multiphase chorus. A "string chorus" effect like the ARP Solina (among others) uses a mix of slow (0.6 Hz) and fast (6 Hz) modulators. These are usually 3 phase modulators to prevent a noticeable vibrato effect, but other implementations use independent LFOs that are close to the same speed (Roland RS-202) or different speeds (ARP Omni). The standard effect is mono and wet only, but there are also a number of stereo variations that pan the modulated signals left, right and center, and/or mix in the dry signal, or even use entirely independent circuits (Roland RS-505). Of course this should be a source of inspiration rather than some sort of "limiting case"; there are many other worthwhile variations.

You may also want a random chorus. Here it's probably best to randomly vary the speed of your modulator. It's useful here to specify a minimum and maximum detune amount.

I'll try to upload some abstractions when I have time to look them over.

How would i insert a sample sound into a chorus patch like this i am having a bit of trouble how to connect it. i too am new to pd.