Spectrum analyser Equalizer project how to go about it?

[Maglatron]

I’d be interested too if you don’t mind emailing to me.

did you end up getting the pdf's

 

[Martaine2005]

did you end up getting the pdf's

Yes.

 

[Martaine2005]

You can get all the colours. But green, amber/yellow and red are quite the norm.

Martin

 

[AnalogKid]

I'd suggest you go 'analogue' with this.

PDF scans of the magazines. Fun fact - For the same month and year, two different international versions of the same magazine had two different audio spectrum analyzer articles. Hmmm . . .

Canada: https://worldradiohistory.com/CANADA/ETI/70s/ETI-CA-1978-06.pdf

England: https://worldradiohistory.com/UK/Electronics-Today-UK/70s/ETI-1978-06-78.pdf

ak

 

[Maglatron]

Nice one for those! , Ive immersed my self in an op amp tutorial from udemy only cost a couple of quid so going to finish that then I will have a look also do you know where to buy the red led bars?

 

[Delta Prime]

like that article any tips on how to make it into say 30 band spectrum and "dance" to the music? do you need to have a chip for every frequency? is there a 20 LED bar driver, because the LM3915 only supports 10, also what are the flat LED's in stacks of 10 or possibly 20 called to find and buy

You can use both chips in the circuit for a unique display both linear and logarithmic the 3914 is a is voltage peak detector and we need to do is get a operational amplifier and a microphone no problemo.

 

[danadak]

Dramatic reduction in parts approach :

Regards, Dana.

 

[kellys_eye]

@AnalogKid - nice find. I got my copies from those sites originally but forgot the address of the site!

 

[Maglatron]

You can use both chips in the circuit for a unique display both linear and logarithmic the 3914 is a is voltage peak detector and we need to do is get a operational amplifier and a microphone no problemo.
View attachment 60509

I don't get it
also a few questions:
what is a filter bank
how can you use a the signals from RCA (white and red)
I've decided that I want the display to be rectagular eg wider than tall
so I want red rectanglur led's and I want them 30 led's tall (76.2mm) and and I want 15 frequencys so width would be (153mm)

HDSP-4850 Broadcom Light Bar LED Display, Green 1.9 mcd | RS

uk.rs-online.com

 

[Maglatron]

practically want the same thing as that but with the led's and controlled with external power supply and the signal from RCA jacks and so I was going to use a splitter cable so that the audio can go into the spectrum analyser and to the midi box that I have

 

[Maglatron]

practically want the same thing as that but with the led's and controlled with external power supply and the signal from RCA jacks and so I was going to use a splitter cable so that the audio can go into the spectrum analyser and to the midi box that I have

Dramatic reduction in parts approach :

Regards, Dana.

also I dont want the bar that bounces off of the top of the columns

 

[AnalogKid]

You can use both chips in the circuit for a unique display both linear and logarithmic the 3914 is a is voltage peak detector and we need to do is get a operational amplifier and a microphone no problemo.

He wants 30 frequency bands, each with an LED bar graph, not a single indicator with 30 steps.

ak

 

[Maglatron]

thanks for the clarification I've settled on only 15 bands now but that circuit may come in handy because I do want the single indicators to have 30 led's high
ok so I'm pretty sure that I need this one
https://worldradiohistory.com/UK/Electronics-Today-UK/70s/ETI-1978-06-78.pdf
but I cant see the tracks on the circuit board and cant make sence of the circuit it'll probably "click" sooner or later

also

You can use both chips in the circuit for a unique display both linear and logarithmic the 3914 is a is voltage peak detector and we need to do is get a operational amplifier and a microphone no problemo.
View attachment 60509

where is the power for the led's on this picture

so the best deal I found is 45 of the 10 led bar display's for £100 the moneys not too much of a problem but wondered if you could source some cheaper ones?

how can you use a the signals from RCA (white and red)
I've decided that I want the display to be rectagular eg wider than tall
so I want red rectanglur led's and I want them 30 led's tall (76.2mm) and and I want 15 frequencys so width would be (153mm)
with the led's and controlled with external power supply and the signal from RCA jacks and so I was going to use a splitter cable so that the audio can go into the spectrum analyser and to the midi box that I have
I've settled on only 15 bands now but that circuit may come in handy because I do want the single indicators to have 30 led's high

Correct me if I'm wrong but does the spectrum analyser do the leds one bar at a time? what will be the results is it so fast that you cannot tell?

 

[AnalogKid]

also

where is the power for the led's on this picture

Upper right - "6 to 12 Volts".

ak

 

[kellys_eye]

but I cant see the tracks on the circuit board and cant make sence of the circuit it'll probably "click" sooner or later

Not much point in using their pcb since you want more channels and a larger display, none of which would be fitted on the board as it is.

As for LEDs you'd be better off bulk buying individual rectangular LEDs like these:

QUANTITY OF 200 PANASONIC 2MM X 5MM RECTANGULAR GREEN LEDs LN342GP | eBay

Find many great new & used options and get the best deals for QUANTITY OF 200 PANASONIC 2MM X 5MM RECTANGULAR GREEN LEDs LN342GP at the best online prices at eBay! Free delivery for many products.

www.ebay.co.uk

 

[Maglatron]

thanks thats realy good but I wanted red especially and I wanted them mounted in a nice neat package can you buy blank packages that fit in 10 but I could maybe make an enclosure It is well worth the money saved with what you're suggesting I might have to compromise with colour but don't really want to!

 

[kellys_eye]

I've decided that I want the display to be rectagular eg wider than tall

If you are UK-based you can have these boards free of charge (postage only) that will give you all the LEDs you need. Sadly you'll have to desolder them yourself or, possibly, use them as-is in some fashion....

288 of each colour red, green and blue. I might have a third identical board somewhere in my 'crap hole' (as Mrs calls it).

 

[Maglatron]

I find it hard to say no really but where I am, I can't use internet banking, paypal or even email, and so it's hard for me to get the postage paid to you, but thanks for the thought It's really kind of you thanks for the thought! sorry to decline!!

 

[kellys_eye]

I find it hard to say no really but where I am, I can't use internet banking, paypal or even email, and so it's hard for me to get the postage paid to you, but thanks for the thought It's really kind of you thanks for the thought! sorry to decline!!

Where are you?

 

[Maglatron]

I tell a lie, I can access internet banking. I discounted it because when you add a new recipient you have to confirm through mobile telephone to authorise the new person added, but I have just thought I can ring up the bank and authorise it that way do you want to pm me your account number and sort code and I'll give it a bash. I'm in the william wake house, billing road, northampton, mackaness nn1 5dg and my name is scott