Home Made Big Blue Audio Spectrum Analyzer

[wabachi]

schematics??

[blalien66]

Nice work!

Was it hard and expensive to make?

And do you have the schematics for it?

[rhblakeman]

A larger version of this would make a good visual effect for a DJ booth, and cheap to build too.

[RaulHuertas]

did you make FFT in PIC software?

[merijnwitje]

soooo nice

[shyy1337]

wich LEDs did u use? Ultra bright or the standard ones? its hard to see.. it looks like the ultra bright but the light is weak as the standard ones

[gavincurtis]

@shyy1337

Ultra bright. But they are working at 1/16 duty which is pushing the envelope for typical full output LED operation.

Regardless, the display is still too bright for normal viewing and hurts to look at directly. The camera electronics have turned the brightness down.

[0175201752]

i didn't know Steven hawking could sing! XD

[shyy1337]

yes i would love to make it... i would rly like a circuit diagram to! ty.

[Nuros16]

very nice^^

can you make a circuit diagram pls?

it´s very cool!

[Cthrilla]

cool make a how to vid!

[kjun13]

I want to build one of these things very badly. Does anyone know ehere I can get a tutorial on how to build one of these (step by step).

I'm gonna build one 1.5' by 2' and attach it to my desk.

[Thrill98]

50hz frec. shows on you display

[gavincurtis]

@Thrill98

You are correct.

[TheOndazzz]

esta padre

[hitachi654]

Hz is the refresh rate (how many times the monitor can update its seft.)

[agentbong138]

What song is that? And what controller are you using?

[Mitsaras69Bithras]

the song is satisfaction...

[Cthrilla]

Benni Bassi - Satisfaction

[tittytwister5251]

jesus!! thats amazing, ive only just started programming a PIC16F627 and only just made the LEDs flash in different sequences, and thought that was good, but this is just simply astonishing!!!!!

[gavincurtis]

6 months before this video was published... I was ecstatic to get my single red LED blinking!

[gavincurtis]

gotta twist that PIC ;)

[waldo2020]

why did you use analog BP filters? Or are you using a low horsepower PIC that can't handle an FFT?

[gavincurtis]

Waldo,

Analog filters look better to the eye at this time. Also, using a slower PIC (like my mind that can't seem to comprehend FFT), it is the best I can do right now.

[ronaldyamid]

can you make one for my ? howmuch and how big would be ?

[BRADHblackdragon]

hi did u cut all the mounting holes yourself?

[gavincurtis]

No, the holes were cut by CNC machine. But pegboard panel from a hardware store would actually work to make a much larger display. LEDs would be spaced farther apart of course.

[jonnyfunguy]

you got a wschematic for this? I've been trying to think about making something like this for ages!

[crackflash77]

Please I need to know that integrate circuit you used to make the vumeter and that integrated circuit usastes for the filters bandpass and of that oreden are the filters 1º 2º o 3º And the size of the box of leds

sorry for my english

[gavincurtis]

LED display is nearly 12" horizontal. Filters are 4 for beauty. IC was PIC16F877

[crackflash77]

Please I need to know that integrate circuit you used to make the vumeter and that integrated circuit usastes for the filters bandpass and of that oreden are the filters 1º 2º o 3º

sorry for my english

[crack77full]

hello gavincurtis. i am student of electronica. tell me please what ic use you for make it?? sorry for my english

[astronomerroyal]

A very polished result.  Are these bandpass filters units that you bought or made? I'm curious to know whether they're made of a high and a low pass filter in series - as one would find in any beginner's electronics book. From my elementary understanding this would make a simple bandpass filter. Thanks for posting.

[gavincurtis]

Hi,

They were built but from a very popular bandpass design.

They are both high and low pass using a single op amp stage. Google "multiple feedback bandpass filter".

[Tymek990]

wow 256leds

[johneymute]

so actualy this audio analyzer could registrates the rithm, the hich,mid and low tunes,drums and voices and the volume of it etc,,?

if so? would be great, sothat i can check wich soundchannel in the famicom is really soft compared with eachother,

[tech33012]

i would like to build mine on a large square do u have a schematic

[ZeikJT]

why do the off lights seem to flicker too? It's not like it need to refresh the ones that are not on.

p.s. nice creation! :D

[gavincurtis]

Smart :)

The problem is the cameral CCD software. Specifically the camera does not know how to deal with high intensity concentrated sources of blue and UV light. If you look at the columns when all LEDs are off, there is no flicker.

The PIC only refreshes LEDs that need to be on.

[ZeikJT]

ah, that's awesome. I wish I could master the art of PIC, but I/O without a computer interface kills my brain.

[Speedsk8tr2]

what's the song????

get back to me asap

[ankoslitoflower]

google the lyrics son.

[zeldamcp34]

Satisfaction by benny benasi..last name might be wrong

[62187ynes]

wow fantastic.!our project in microcontroller is similar to yours...but i really dont have idea how to do it using PIC..well be using PIC16F628..will it work?i've seen schematics similar to this project but it uses an ordinary IC not PIC..i really need your help!f u dont mind...GODBLESS..

[gavincurtis]

The 16F628 could work but since it has a small number of I/O, it would require external latches to drive the display.

I chose the 877 because it has enough I/O lines to directly multiplex the display with no additional external logic.

[62187ynes]

its so nice...our project in microcontroller subject is similar to yours but i really dont have an idea how to do it..well be using PIC16F628..will it work?pls. help me..tnx!

[russelli1]

this display is the best i've seen.i used to have an Audiocontrol rta/eq. and i was really just interested in the display.i would really like to acquire one of these,if you start selling these, post it plz.great job.

[FelisSilvestrisCatus]

As I have just posted in your other video;

You could probably have achieved the same with at least 100 times less electronics, and a little bit more programming. :-)

One PIC (or some uC) with one ADC and a programmed FFT should be enough.

[gavincurtis]

So you implying a uC for display control. Then include another device for analog to digital conversion....

Then rely on a FFT enabled device to process input?

Wouldn't it be easier for the FFT device to directly steer data into the display uC and bypass the ADC completely?

[FelisSilvestrisCatus]

uCs w/ analog input and built A/D C are available today for only few $. Also, they are so powerful they can run FFT or DFT without any problems.

[gavincurtis]

Felis,

I have to agree that FFT is the ideal solution. But I have yet to see results.

One IC. Not a PC or full size motherboard... just a single DSP IC with FFT to do the same with same output resolution.

Many compact stereos are trying to implement you FFT methods on their VFD displays.... and they fail.

FFT is indeed very accurate, but it lags behind the signal and misses much of the information. Especially at high frequencies. Just like MP3... much of the information is lost.

[FelisSilvestrisCatus]

It depends on sampling rate.

I don't have some concrete measurements at hand to support it, but I'm sure it's possible to attain such small lag that human eye will not notice the difference on some simple spectrum analyzer..

[gavincurtis]

Another technique is to switch filter elements such as capacitor or resistors. Another youtuber built a 32 band using 4 filters.

[gavincurtis]

If you have the FFT solution using a single processor under $40.00 that looks as good as my dot mode video.... then awesome! :)

[gavincurtis]

If you get it under $40.00 CPU cost alone.. please share!

[FelisSilvestrisCatus]

ok, if i do, i'll share it with you :-D

[bg11390]

That's great. Do you have a schematic? or Kit? I know there was talk of it :)

thanks

[mdmde]

look up national Semi MF10

[gavincurtis]

Thank you mdmde. I didn't know they had such a device. It appears to be phased out from production.

[cutterschoicenotmine]

nice work my friend.

i would put $100 (thats about 25 of my money) on 3 facts.

1. You don't get out much

2. You havn't been laid for a while

3. You drink one hell of a lot of coffee!

[gavincurtis]

You want it :)

[envisionelec]

Neato. I did a big one in a set of car tail lights (yup, left and right) before PICs were big. I used MFB filters, 4066s to switch the channels in time with a basic mux circuit driving an LM3915 to an array of LEDs. Also neat is putting them into a hacked defroster grid in the back window of a vehicle.

[gavincurtis]

SO why are you marketing? Give up subwoofers and go into lights.

[gavincurtis]

I meant to say why are you NOT marketing yoru skills?

[envisionelec]

Subwoofers? I build specialized audio equipment...a few subs here and there. My passion is amplifiers and LEDs. ;)

[gavincurtis]

LOL.. my sub-conscience was speaking. ;)

Usually the subs are first thrill, then the LED bling follows. If your retrofit was indeed using rear window defogger lines as part of the multiplexing.... drive your creation around in Las Vegas for a few days showing off your ingenuity.

Your family will longer be hungry. :)

[gavincurtis]

That is meant to be understood as a compliment envisionelec! :)

[freeridermaster0987]

what is the name of that song, cool thing ;P

[ubek123]

benny benassi - satisfaction

[hubwah]

what is the name of that song

[mdmde]

Active bandpass filters? switched capacitor filters?

or FFT?

[gavincurtis]

Hi mdmde

Resistors are usually easier to switch than capacitor values unless you know something I don't. ;)

[dk01945]

Hi, would I be able to pay you to make one of those circuits for me and program it.

[joeylawn36111]

Very Nice. I do the same thing, but I purchase older spectrum analyzers and remove the (usually) dim red ones and replace them with blue LED's or I use several different colors.

[beavisul]

will you please be so kind and give to the rest of the world the schematics of that? i want one of those things

[gavincurtis]

Schematics to build one of these has been out there for some time.

[beavisul]

well i didn't find one(as big as this) anywhere...

[gavincurtis]

I built this in 2001-02. I had nothing but technical problems afterwards. A crashed hard drive and then more. I had all backup schematics and firmware on a USB flash drive and it has somehow gone into the ether too. Even hardcopy paperwork is gone. It feels like somebody cleaned my clock...

I have to start this all over again. To light a fire under me, I put my 6 year old prototype here to see what it would take to get me to make this machine over again.

[tormodk]

do you have a link for the schematic?

[gavincurtis]

Not trying to be an elusive jerk. But the schematic I used it on the internet and came from a German kit manufacturer. Then I built upon it and made it better.  :) Not cheaper... better.

[gavincurtis]

PIC code is awkward at first... then it all makes sense after some time. Keep an eye on that W register :) That is a math result aka central register where the work result is written and then transferred to other memory location.

I don't know why... they said W

[TexZK]

W = Working register.

Anyway, how do you analyze audio? Are you using FFT? Can you contact me by PM? I'm very interested because I like PICs ;)

[serjster]

Hi what configuration did you use for the bandpass filters?? I'm trying to do something similar. But it will be very hard to match up yours.. Thanks.

[asiguere]

dude, would it be too much to ask you for the code you used on the PIC...because man, I've always been afraid of the PIC set of instructions :(

and man, it's amazing you did that array yourself!

respect

[artist082483]

What would it cost if I got you to make me one!!!?

[gavincurtis]

I completed this project self educated some years ago. It's the most complex system built by my hands to date.

It's not antigravity! But I am very proud of it.

[Paulendy]

nice!!!

[artist082483]

Im in the same boat as iunias. i think it would be sweet right below my 40 lcd tv.. but the question is. is it possible to make one thats 40" long by 6" tall

[gavincurtis]

Absolutely... dot mode would be perfect. Imagine a SA wave filling that 6" horizontal space while watching a movie.

[iunias]

dude this is awesome.. is it your own design or??.. by the way could we get the schematics? coz i want this!! :D

[gavincurtis]

Patience is my middle name :) I'll show a 4th video from the backside of the LED array. The LEDs are inserted from the backside of the board... full day of assembly.

The most difficult part for me however was learning to program the microcontroller.

[brianhoskins1979]

Nice work. If you look carefully, the camera picks up on your display multiplexing.

Brian

[gavincurtis]

What the camera has seen, the human eye is patient and understanding. ;) Otherwise a 5 amp power supply is required to light those LEDs.

[brianhoskins1979]

Hi Gavin.

Yeah I'm sure the eye is far more forgiving than the camera is!

You have 256 LEDs on there so assuming approximately 20mA for each then yep you're looking at just over 5Amps when they're all on. There's no doubt that it's better to multiplex!

I'm quite impressed with the response of the analyser, it's turned out quite well hasn't it?

Brian

[gavincurtis]

Thanks Brian.

Response time is impressive so far. The analog filter stages emulate the Cochlea from what I understand about it so far.

Just has to be a less expensive way to make an analyzer like this though.

[gavincurtis]

That is; the highest frequency response of the inner ear neurons are 5 kHZ. Brain gets no data above 5 kHZ from any neuron directly. Yet we hear audio 18+ kHZ in realtime!

[gavincurtis]

Built the LED matrix using standard 5mm blue LEDs and soldered them onto the circuit board. Circuit board was painted black first.

[gavincurtis]

Thanks! If and only when I can program a DSPIC! But I think analog front end has the true real time computing ability such as this.

[Alu10000]

Wow! Amazing!