Does a Customize-able Led Visual Music Display Exist?

I might have used the wrong name in the title, but here's an example of what I am talking about with way more bars than I could be anywhere near:

Basically I want that effect, but with this grid:

I've seen a few sound projects before, and I know that most of them usually involve having an audio file set-up before hand. What I'm wanting though, is to take the signal directly from the blue tooth receiver and convert it into the pattern as it's also playing through speakers. It would be cool even if I had to have set-up files, but this speaker is going to be on the go often and it would just be needless then.

This is going to be a part of a larger project, and all 4 LEDs in each blue square can be connected to one output pin. Again, since I have no experience on this topic, I wanted to plan for the worst. I have no idea how many pins the programming would need to meet these needs. Sacrificing 18 pins will be hard (one for each 2x2), so if this is possible to do this with any less I'll take that opportunity. Also, at the moment this grid is very bulky with a 2x2 set of LEDs being each level indicator so I would also shrink that if I can as well.

What I had in mind was a program that had already been created that could be easily adjustable to fit other sized grids like this one. If that kind of program doesn't already exist, this is going to be a bit more difficult.

If I am not making any sense ask me a question and I'll answer it as fast as I can!

Thank you for your time!

What you need is FFT,. Search the forum for it.

When it comes to the wiring it all depends on what you want.
There are a million ways to build it.

What you are looking for is called a spectrum analyzer. A spectrum analyzer is actually a scientific/engineering instrument, but I think you want a spectrum analyzer effect. (You are not trying to make accurate measurements.)

With an LED spectrum analyzer, each column of LEDs represents a frequency band with low frequencies (bass) on the left and high frequencies (treble) on the right.

DISCLAIMER - I've never made a spectrum analyzer.

This is going to be a part of a larger project, and all 4 LEDs in each blue square can be connected to one output pin.

So, that's 6 frequency-bands. There is a nifty 7-band chip called the [u]MSGEQ7[/u] (available from SparkFun). It takes a line-level signal, filters and "measures" the levels in 7 different bands, and multiplexes 7 varying DC voltages into one Arduino input. It requires some special programming to "read" the 7 voltages at the right time and keep them straight, but you can download it and it's a LOT simpler than FFT. and, one chip takes care of all the circuitry on the input-side (two chips if you want stereo).

If you don't want to use all 7 bands, you'll still get good "LED action" out of whatever bands you use.

Sacrificing 18 pins will be hard (one for each 2x2), so if this is possible to do this with any less I'll take that opportunity.

If you don't need dimming and you don't need to control RGB LEDs, The most common solution is a shift register. A shift register takes-in serial data (a sequence of ones & zeros) into one pin (plus a couple of control pins). The output comes-out in parallel with as many bits (or LEDs) as you wish. [u]Here[/u] is some information to get you started. I recommend that you experiment (and learn) about shift registers before you jump-in and try to build the whole project.

I know that most of them usually involve having an audio file set-up before hand.

Usually not... Especially an effect like a spectrum analyzer that's supposed to look like it's controlled by the music. You might find something like that pre-programmed when the show is repeated over-and-over, such as a stage play, a big concert tour, or a show at Disneyland, etc. But most "dance" lighting effects are sound-activated. Most "dance" lighting effects that you buy (such as American DJ or Chauvet) can be either sound activated or DMX controlled. DMX can be programmed, but DMX lights (and stage lighting) are usually operated by a human at the "lighting board", sometimes along with with some programming.

I built an 8-foot tall "Giant VU meter" effect with 24 LEDs in each channel (left & right). (It only works off the volume, nothing is frequency activated.) I used 3 [u]MAX6978[/u] chips cascaded together in each channel. I only needed 4 Arduino outputs and I can individually control/address 48 LEDs. Each channel has it's own data pin, but the clock and latch pins are shared. Since I have a microcontroller and I can address the LEDs individually.... This effect randomly runs in the normal "bar" mode, "dot" mode (one LED on at a time), it runs in reverse (top to bottom), and inverted (LEDs turned-off with sound instead of on), and it does 7 other sequencing effects with many different patterns & options.

There is a great tutorial using Teeny, the FFT, and neopixels to make a spectrum analyzer display, which I can't find, but I did find this :

Not the best or most detailed explanation of the FFT, but probably enough to get you started.