FLAG x Omri Cohen Prism of Perception (Advanced Delay + Looper)

Squinky · August 27, 2024, 4:06am

a “fix”? I don’t think there is an acknowledged bug here, is there? I also don’t think there is a promised enhancement?

jnorberg · August 27, 2024, 7:21pm

Yeah, there is/was a bug with reloading the buffer. It only worked properly if you were running at 48k. (the bug was that the buffer was cleared when the sample rate changed and the loading happened before I knew the sample rate so that the buffer was thrown away once I saw the sample rate for the first time)

I have fixed it and gave it to Andrew. I think he’s busy so I can not guarantee when the library will be updated

jnorberg · August 29, 2024, 4:38pm

The fix should be available now!

Prince 2.2.6 → VCV Library - FLAG Prince Of Perception

Prism 2.0.3 → VCV Library - FLAG Prism of Perception

kirkwoodwest · September 1, 2024, 12:26am

Is there any way to clear the buffer without using the right click menu? that would be super useful.

Also if anybody has any good chains to use in the feedback loop that would be great. Looking for some effects like the DL4 tape looper. currently experimenting with the chow modules but its difficult to get the volume dialed in for 100% feedback.

kirkwoodwest · September 1, 2024, 5:58pm

I wanted to share my experience using u-he Satin with Host-FX, which turned out to be a fantastic combo for me. It seems to get the job done without much effort, which is always a win. One thing to note: I had to disable the “Use worker thread” option to fix some buffer glitches. I set the block size to 1024, and so far, it’s working pretty well.

I’m basically using this as a long in sync tape loop and keeping feedback around 90% and having it record to tape every loop so the degradation compounds. and then I add layers on top.

However, I’m not entirely sure if it will stay in sync, given the buffer situation. There’s always a bit of uncertainty there—kind of like time travel with these loops, right? Does anyone know a good way to test for drift? I’m not hearing any audible chorusing or clicking… Any tips would be appreciated!

Also, I’ve noticed something odd with the reverse function. When I record a loop and hit reverse, that loop plays backward, which is expected. But any new parts I record afterward don’t seem to follow the same reverse pattern. It feels a bit disjointed because I would love to be able to record new parts in the same direction as the playback. so like the new forward parts would get written together with the reverse parts. and then if i press reverse again the original parts would be forward and the new parts would be reverse.

By the way, I hope this feedback is helpful and comes across nicely. I’ve been diving deep into different loopers lately—Augustus Loop, Enso, and recently stumbled upon Prism of Perception. I have to say, Prism of Perception checks off most of the boxes for me. The ability to insert custom effects between each loop is a game-changer, allowing for some really unique and creative setups.

Squinky · September 1, 2024, 6:41pm

I believe all instances of host will introduce at least one BUFFER of delay. Much more about that here:

github.com

squinkylabs/Demo/blob/main/docs/host-delay.md

# Host delay

The VCV Host plug-in works super-well to integrate VST into VCV. It's a paid plugin, but most people find it well worth the cost, especially if they already have a bunch of VSTs.

Sometimes a VCV user has a choice between a "native" VCV module and a VST that does something similar. We believe there are reasons to prefer a native VCV module, when possible:

1. The native VCV solution is probably free.
2. Host + VST will often take up more screen space.
3. Host, by its nature, will introduce a delay.

The first two are pretty obvious, but the third one, delay, is less obvious, and perhaps not understood as well. So we will write about that.

Note: all testing was done with the Host-FX plugin.

## Measuring delay

This is a basic setup for measuring delay. Here we are running a low frequency square wave through Host and the session is set to a 44.1 kHz sample rate. Host has loaded a VST EQ that is set to bypass. We are using the Submarine Envelope Scope, since it is really good for measuring the time between different traces.

![Delay setup](./host-delay-setup.png)

This file has been truncated. show original

kirkwoodwest · September 1, 2024, 7:23pm

Very enlightening thanks for putting that together.

I guess that means using host inside the feedback line will cause the delay to be out of sync. touche’… i’ll continue to try to put together a convincing tape effect using vcv material.

kirkwoodwest · September 1, 2024, 8:19pm

Another cool combo using airwindows… Not as fancy as the u-he Satin, seems a little easier/predictable than using the chowdsp

Thanks to @Squinky pointing out the block size is a real threat to this. Air windows offers an adjustable blocksize and at much lower amounts. I have set here to 4 and the prism of perception to 5 samples. I’m able to sync a drum machine running into vcv rack with this virtual tape loop and its seamless.

Squinky · September 1, 2024, 9:00pm

fwiw, most VCV modules have a block size of one sample. There are very, very, few that do block based processing like this.

kirkwoodwest · September 2, 2024, 6:10pm

its great. and super good to know how to test as well. it would be great to somehow run a test within the Prism of perception to capture the delay time of the feedback loop and it would automatically set it… not sure if that is really even possible but it would be great. or at least be able to set the sample correction beyond 8 samples. Of course I have no idea of the effects that would have on the plugin but for me it would certainly open up a lot of possibilities here.

jnorberg · September 2, 2024, 9:49pm

The sample correction is mainly for the volt per octave mode, where the number often would correspond to the numbers of modules in the chain from send to return.

For long latency, send return, just lower the delay time by the same amount