LED audio meter


Looking to create the classic audio meter on old boombox that’s a series of leds from green on the left through yellow and orange to red on the right. Basic audio reaction, low level is green, high level lights up through red.

I know how to do this in AE, but trying to avoid a list of things to do in post, and working on a boombox design now, so wanted to get some opinions on easiest way to achieve this. Ideally, I’d love to just find one that’s premade that I can reshape. Not seeing it, though, so…

Seems potentially resource inefficient to create a series of little rectangles that is each fed by a separate trigger via sound effector. Easier perhaps to do it somehow as a single solid, then create a grille to go over it that separates it into separate bits? Not exactly sure how that would work.

Anyone got a short cut to get this cranked out quickly?


The quick way would be AE.

If it has to be done in C4D, I’d probably do it in AE and use the render to drive a cloner/shader effector.

Or as you’re suggesting in your own post, use an AE render, but then put it on a plane in cinema and then create a grid in cinema and place that however you think it works best in front of the plane (with your AE render on it).

Either way should be pretty quick.


Can’t quite picture what you mean about driving a cloner / shader effector by a clip of rendered video.

Just a thought… Anyone tried anything like this somehow maybe driving multishader with predefined green, yellow, orange, and yellow steps per led, and calling them by index… perhaps in conjunction with instance, array, or other procedural clone that can refer to each via an index? Vaguely familiar with these things, and trying to decide which to dive into.

I’ll do it by AE if it becomes too impractical, but trying to set up a c4d template that I can reuse, so looking to keep the future workflow simple with a plug and play template if possible vs back and forth between apps.


Apologies, I meant Cloner / Material. Create your LED animation in AE, bring it into C4D as a material, I’d suggest the luminance channel, untick color.

Create a cube, drop it in a cloner, designate your X & Y clones that match up appropriately to your AE render.

Apply the material to cloner. Switch the projection in the material tag to Flat.

If you have the sizes right, your AE LEDs should line up with the cloner’s LEDs. You may need to adjust things a bit, but shouldn’t be too much of a problem. Here’s an example I did in under 10 min.


Ahhh… ok. Interesting. I’ve seen clones colored equally or randomly, but wasn’t aware you could do the wall of tv’s as a single object thing.

That will probably be the easiest path.

Still interested in any native c4d options too as I’ve been using this project as an excuse to learn how to do as much as possible in c4d. I’m sure I’ll be doing more music videos in c4d in the future, so trying to build template assets and learn as much as I can about things like sound effector in the process.

Actually, the technique you jsut brought up may be very useful in other ways. Old band I was in did shows where we had a bunch of dancers in flowing white clothes, and a guy projecting visuals onto them. Seems like some version of flat projection onto moving clones could be very interesting.



a way to do this full 3D is to create a linear cloner with a cube in it, number of clones and spacing to whatever you think looks good, duplicate it, and put clone number down to 1. Put both cloners in another linear cloner with clone mode set to blend.(number and spread however many you want). This will create a sort of set of cloners with count from 1…whatever your upper limit was. Add a sound effector with parameters all off, but modify clone at 100%.

Load sound and make the probe(the sound sampler bit in the effector) as wide as possible. Then change sampling from peak to step.

Should now make the cloned cubes appear and disappear like an equalizer.



Got that working. thx.

Replaced off state with 0 instead of 1 clones to allow visual for total silence. Only way I could work out to show off state as persistent but grayed out was to create 2 sets (one for on state, and one for off) On State covers and hides off state when present.

Colors are unstable, though, as indexing shifts to apply to however many are present at any moment rather than total possible.

EDIT: Uploaded file cleaned up and replaced with one 3 posts down.


Stablized colors and flipped so on state is ever present, and off state covers them via inverted sound effector.

EDIT: Replaced this upload with cleaned up one 2 posts down.


You can use the sound effector sample strength to drive the count of a cloner to show level, with some dummy (slightly smaller) clones to represent led off.

leds.c4d (237.5 KB)


OK. Good to see some different ways of approaching it.

Either at this point works effectively tor the nested approach using 2 separate sets of LED’s to represent the 2 states where the presence of one hides the other.

Is there a way that deals with the color or material change directly with a single set of LED’s?


While I was originally going for 80’s authenticity with the 4 stepped colors, the gradient does look more aesthetically pleasing overall, IMO, so I worked out a compromise that generally follows the 4 step coloration contour, but smooths it out, and gives slight visual consideration to the fact that bottom (green) end of the scale is nearly always lit while top (red) is more transient. Basically several compromises to lend to a balanced if not period authentic look.

Stepped material is included, so just swapping it for the gradient should achieve the stepped look.

LED sound effector.c4d (7.8 MB)

Not sure if there’s a better way to spread gradient across clones. I just played with shader projection options until one worked.

I am still curious about a solution that just changes the color of each from off (gray) to it’s on-state gradient rather than this dual set with one covering the other if anyone has an idea how to do so.

Also interested if there is any way to enter decay values less than 1 in sound effector, or achieve similar end. Zero is so jumpy as to be distracting, but even a value of 1 is too slow to represent the classic LED indicators as I remember them.


If you’re into Python, you can do all kinds of clever LED displays. A few years back, I had a go at LED with peak detect that holds for 1 sec then drops example here.

In this file I used separate LEDs - made the math easier.

channel.c4d (324.1 KB)


I haven’t ever dug into python.

Then again, I’d never taken a crack at javascript until I was forced to while working out some After Effects issues, and there were enough online resources that it didn’t take long to get some basic scripting done.

Will take a look at file when I have more than a couple minutes to do so.