The Ultimate Audio Converter





Introduction: The Ultimate Audio Converter

I always find myself wanting to convert between mono and stereo and 1/8" and 1/4" jacks and never seem to have the right adapter on hand. The other day I was making two separate adapters for two separate conversion tasks when I had the sudden brainstorm to make a panel with every single mono to stereo and 1/8" to 1/4" conversion path I could reasonably think of. And with that in mind I bring you the ultimate audio converter.

It can convert from 1/8" or 1/4" stereo to either 1/8" or 1/4" mono (with the option to change jack sizes between channels). It can do simple conversion from 1/8" to 1/4" in mono and stereo. It can even split a mono signal into a stereo signal (again, with fully selectable 1/8" and 1/4" conversion options).

It is my hope that I will never need to make another converter again!

Well... until I need two of the same kind.

Step 1: Go Get Stuff

You will need:

A 14" x 12" sheet of white acrylic.
An awesome Epilog laser cutter
Red and blue acrylic paint
A paintbrush, water cup and palette
A heat gun
Heat protective work gloves
An 18" metal extrusion
Table clamps
A ruler
A drill with a 1/4" bit
(x2) 3" carriage bolts
(x2) 1/4" nuts
(x2) rubber stoppers
(x6) 1/4" mono jacks
(x3) 1/4" stereo jacks
(x6) 1/8" mono jacks
(x3) 1/8" stereo jacks
(x4) SPDT rocker switches
A DPDT slide switch
Hookup wire
A soldering setup

If you don't have a laser cutter, you can use a service like Ponoko

Step 2: Laser Cutter - the Tool of the Future

First you will need to cut up your acrylic.

Using the files below, first make a raster cut with the following settings:
Speed: 100
Power: 100
DPI: 600

Then make a vector cut with the following settings:
Speed: 10
Power: 100
Frequency: 5000

Step 3: Paint

Neatly paint in the part that was etched away with dark purple paint. For an added touch of class, also paint around the outside edge.

Place it elevated and flat so that the edges don't touch anything and you can pick it up from underneath if need be. I balanced mine on top of my water cup.

Wait for it to fully dry and then peel away the protective coating.

Step 4: Bend

Using your table clamps and the piece of metal extrusion, clamp the board to your heat resistant table such that 6" of the board is sticking off the end as shown. Make sure that measurement is even on both sides.

Put on your work gloves. Heat up across the joint (where the board is clamped) until it starts to visibly start to droop a little. Hold the part of the acrylic farthest from the heated edge (the coolest part) and gently and evenly start to bend the entire panel down. Continue bending until the panel is at around 45 to 60 degrees.

Hold it in place until it starts to cool and stiffen and then unfasten it.

Step 5: Install a Stand

Clamp the rubber stoppers in place and then drill a 1/4" hole into the top of the stopper such that it goes most of the way through.

Install your carriage bolts into the top corners of the board, fasten them tightly with 1/4" nuts and then screw the rubber stoppers onto the bottom.

Step 6: Jack It

Install all of your jacks as they are labeled on the front side of the board.

This means, removing the nut from the threading, pushing the threading through from the backside and then refastening the nut. Easy!

Step 7: Wire It Up

Place your board face down on a piece of felt or an unloved t-shirt.

Wire it up using the following schematic.

Unlike me, be careful to pay attention while you do it so that you don't wire everything wrong and realize halfway that you have to redo all your work.

One you are done soldering, you are ready to start converting.



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    Isn't it nice how some projects specify tools that the average hacker can't afford? :P Laser cutter? Come on!

    Or, you could possibly hack this with a power drill, a dremel and some screen printing.

    I don't mind using laser printing on decal material or maybe a clear label if you don't mind the edge. My way of hiding the edge of a stencil or label is to utilize a border of some color for the cut line.

    dude i thinkg the average hacker would HACK not just follow

    I like this! I've been in so many situations where I needed a converter, and I just mostly electrical taped together different adapters to solve my issues. This will come in handy.

    4.7k in line on every out screw terminals are very good for this as you can
    feed a thin copper wire across the terminal to form a bridge to tie in your resistors assuming you are staying passive

    How much is a a basic Epilog laser cutter/engraver?

    I think the cheapest model is somewhere around 8K

    plus shipping :P