Talk Box by Hacking Canada DIY

[St0rm]

Hey All,

Visited an electronics store today looking for replacement components to my Tube Screamer clone and found a kit for a 7W speaker amplifier for pretty cheap. Figured that I've always wanted to build a talk box and all you really need is a small amp, a cone to pick up the audio, and the tubing so what the heck. The schematic it came with is simple enough, input (in this case I'm substituting a 1/4 stereo Jack), a 1/8" input for Walkman amplification, the PCB, a volume knob, power supply, and output to the speakers. Thing is, I'm not an electrician but I really want to hack it and add a few things:

-I'd like to add an output jack with foot switch to bypass the audio away from the speaker and on to the next component.
-LED indicator for the power (easy enough)

And I'm not sure how best to go about it. True Bypass with a 3PDT is dependent on the output from the PCB going direct to the Jack and I'm wanting either to bypass the board completely or split the output from the board (probably a bad idea...)

Seems like the simple solution would be to use some sort of stomp switch and run the signal from the input Jack as well as the 12V power source through it. When engaged it passes the signal and power through to the PCB. When disengaged it cuts the power and directs the signal to the output Jack. Again, not an electrician so this might work, but a part of my little physics knowledge is concerned with signal degradation and the possibility that the output would be just far too small. With that said, for safe measure I've been using 16 gauge wire in the enclosure.

I puts a link to the diagram here:

http://www.canakit.com/Media/Manuals/UK153.pdf


Any ideas or input would be greatly appreciated!!!

[GibsonGM]

I did the same thing, altho my little practice amp sends audio to a speaker DRIVER, which is really the heart of a talkbox...you can probably get by with an actual speaker if you had to, altho it is not authentic.   You could replace the speaker later when you find a driver...   What I actually have going on is an A/B box that sends ALL my signal to the little talkbox amp, or back to my signal chain.  This seemed much simpler to me...you probably won't use many effects if you are talkboxing, so my dirty practice amp is way more than I need!

I used a SWITCHING JACK (1/4") to disconnect the internal speaker when a speaker cable is inserted, which ran to my talkbox.

If you DO want to run this in your signal chain....Read up on 'bypass switching' for how to insert and remove this from your signal chain.  You will need to also come up with a way to direct this little amp away from your BIG amp (beware...) 4pdt switch, perhaps?    Here is a document showing many ways, including LED, and just replace YOUR circuit for 'effect' circuit....http://www.tonepad.com/project.asp?id=35

You'll need to get an enclosure from Smallbear electric or somewhere, and a 3PDT stomp switch.   Plus LEDs. 

Think about just 'switching in' to this talkbox amp, and switching back to your regular chain; very simple and effective.

[St0rm]

Doggon it... I forgot about using a compression driver. Better look into that. I think I got it mostly working. I have a 4pdt switch with a true bypass wiring and output Jack that seems to work, though I still get some hiss... Of course as I type this reply I come up with a way to both cut the power AND fix the LED issue I've had without buying new parts... Dunno why I didn't think of it earlier.

Thanks for the link to tone pad, that's a marvelous resource and a very clear diagram. I'll definitely be keeping that on record.

Having trouble finding a place to purchase a tiny compression driver. Any hints anybody?

[GibsonGM]

Good deal Storm, by the way, welcome to the forum
Let us know how it comes out!    Little sound clip/video is always appreciated!

Here, this guy lists where to find a driver:   https://www.youtube.com/watch?v=cGsoi-SA2qk

If no luck, try Ebay, too.  They are around, not very expensive if you look....good luck!

[DougH]

When I was in junior high in the early 70s, my bud and I made a talkbox by hooking one of these up to one of our amp speaker outputs and putting it in our mouth.

Worked pretty good, although eventually I'm sure we would have burned it out.