Voice changer as a guitar pedal problem

[Jamforthelamb]

Hi everyone.

Ok, so here's the deal. I was tinkering with a voice changer, and I planned on making it into a guitar pedal. The really cool thing is that it uses a lm386 chip in it, so I was able to use some of the fuzz options with the chip. I got all the mods wired up, get it all mounted into a test housing, run a casio mt-35 keyboard that I use as a test subject through it, and all works well. Plug my guitar into it, and no sound gets through. This thing only runs on 4.5 volts, so I wasn't sure if it's an issue of lack of voltage, or if I need to change some components around to make it pick up the guitar. I would really like to get this thing working with a guitar because it sound awesome! Help!!!!

Thanks,
JFTL

[b_rogers]

do you have a schematic for the voice changer? try putting a pedal in front of the changer and see if that works...


Brent

[Jamforthelamb]

No I don't.
It's actually a kids toy that I'm modifing.

JFTL

[A.S.P.]

might need a high-impedance-input buffer in front of it,
and maybe a little amplification...

[Jamforthelamb]

Any schemo's for me ? I'm kind of a noob to all this although I have built 3 pedals now.

JFTL

[jbm222]

check out the boosters & routers section on GGG or Jack Orman's mini booster at muzique.com

There are several ways to build a simple single opamp/transistor buffer/amplifier.  For something like this were fidelity is probably not an issue, i'd aim for whatever you have on hand.

[Tim Escobedo]

Maybe the input needs to be AC coupled?

[Jamforthelamb]

Thanks JBM, I'll do that.

Hey Tim, Love your circuits!

Could ya translate that for me ? I'm kind of a noob to all this.

JFTL

[Paul Perry (Frostwave)]

Could ya translate that for me ? I'm kind of a noob to all this.
JFTL

AC coupling?
That is, put a capacitor between where the signal goes in, and the main circuit, so the signal has to go through the capacitor. A 0.1 microfarad one would be OK.

[Jamforthelamb]

Thanks!
I'll try that.

JFTL

[RLBJR65]

Sounds like a fun project! No schem. how about some pics?
LM386 will do some wierd stuff on its own at only 4.5 volts!

Richard

[Jamforthelamb]

Yeah, since this is a circuit out of a toy there's also an smd black blob chip, so there's no way for me to know what's in there. I think that any toy voice changer that runs on 9v will work for this. I'm still trying to get this 4.5v one to work  .

I may take some pics, and do a little write up on my site for it. I link it here when I do.

Merry Chirstmas!

JFTL

[Xlrator]

Yeah, let's hear some sound clips.

Is the toy cheap and still available?

[Jamforthelamb]

Here's the actual one I'm using off of ebay:
http://cgi.ebay.com/WINNIE-THE-POOH-MEGAPHONE_W0QQitemZ6021320938QQcategoryZ19251QQcmdZViewItem

Like I said, any of the toy voice changers (especially the ones that run on 9v) should work. I get most of my stuff like this at local thrift stores for 5.00 or less.

Here's a sample of another one of these I did before I knew anything about pedal building. http://www.soundclick.com/bands/songInfo.cfm?bandID=264683&songID=3087730
Had I known then what I know now I would have looked to see if it had a chip I could tinker with.

JFTL

[Xlrator]

I just listened to some of your samples of other toys you made. Some pretty demented sounds man!! That wrecking ball sample sounds like something out of a horror movie with possesed toys. Crazy!

"Bye, bye, bye, chicken, chicken......."

[Dan N]

If you want a chip, smallbear has the HT8950 for $5.00. Otherwise, yopu'll have to find a really old voice changer megaphone or crack open one of those Playskool Mr.Mike voice changer/cassette recorder thing.

The toys do put some dc on the input because they use those little condensor mics. I don't know how that would affect the ac from your guitar.