I need a simple schematic that inverts, and/or lowers the pitch of an analog audio signal?

My latest attempts with a bunch of Op Amps has failed again to give me decent results. I would like to be able to lower the voice of someone high pitched, in order to sound more like mine or lower.

Can anyone find a pin out and data sheet for the obsolete dedicated IC that does this, namely the WIN8072?

31 answers
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Feb 3, 2009. 8:21 PMCameronSS says:
This is the datasheet for the WIN8072, to which alex linked below.

Direct link.
datasheet.pdf(595x842) 132 KB
Aug 27, 2009. 1:16 AMVIRON says:
Inversion sounds weird but it is simple, just use a pure tone oscillator of high pitch maybe around 2 octaves up from middle C and a ring modulator and an equalizer. Even weirder if you get it to lower the pitch because there will be a linear shift instead of a musical shift, and probably would require two of every circuit. To do musical note correct pitch change you need either granular synthesis or a digital convolution, although I described a possible analog equivalent in a similar question. (recording and playing a very small loop at different speeds at the same time works) New idea I haven't tried: using one phase locked loop to control another which is tuned to a different center frequency, because using binary counters as frequency dividers just turns sound into pseudorandom noise.
Mar 10, 2009. 4:02 PMjokerlz says:
I made a bat listener which divides the frequency picked up by a bat (40KHz) using a 4040 cmos chip. The chip is a binary counter so each pin divides frequency by two so depending on where you connect the output you can vary pitch. The sound is a bit crackly when it comes out of the speaker but other than that works well.

This is a link for datasheet for 4040http://www.9h1mrl.org/workshop/ChipDataEbook-1d/html/4040.html

For my circuit I had to run the signal from the microphone through two LM 386 chips to amplify it.
Mar 11, 2009. 10:39 AMjokerlz says:
No I didn't. I got the basic circuit diagram from a magazine and the circuit I ended up with was very similar so I was worried about posting an ible an the grounds that it's not really mine (not all of it anyway) and I could get in trouble regarding copyright. Maybe I'll post it in a few years time.
Mar 11, 2009. 10:41 AMjokerlz says:
After. Before the sound was inaudible. I guess that doesn't help much.
Feb 1, 2009. 2:54 PMSandisk1duo says:
did you try using capacitors and inductors? caps clip low frequency inductors clip high frequency if you use a cap and an inductor, you'll clip both high and low frequencies, leaving the mid ranges
Feb 1, 2009. 5:23 PMSandisk1duo says:
did i give you the wrong advice?
Feb 2, 2009. 6:50 AMSandisk1duo says:
i have an idea.. get a voice changer and circuit bend it
Feb 2, 2009. 3:28 PMSandisk1duo says:
just buy something like this

link
Feb 2, 2009. 5:32 PMSandisk1duo says:
you'll end up buying a chip for $7, then buy some more stuff for $10

don't attempt to build one based on the chip they use....

buy one prebuilt
http://electronickits.com/kit/complete/surv/ck211.htm

or copy the schematic
Feb 2, 2009. 5:34 PMSandisk1duo says:
omg, i noticed something....

i just found the schematic for the win8072,
http://electronickits.com/kit/complete/surv/ck211a.PDF page 4
Feb 2, 2009. 7:51 PMSandisk1duo says:
scroll up 3 comments...
Feb 2, 2009. 8:29 PMSandisk1duo says:
found a datasheet
Feb 2, 2009. 10:18 PMSandisk1duo says:
open with something OTHER then ie open with adobe acrobat reader it opens
Feb 3, 2009. 7:06 PMCameronSS says:
Here, I uploaded it through Instructables... Visible in-browser here, and attached below.
datasheet.pdf(595x842) 132 KB

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