I couldn't find a simple audio level/line mixer for sale anywhere that was small enough to carry on the bike. I guess autocom solves this problem, but the price tag is hefty.
My set-up needs? I have 3 audio devices I wanted to listen to in stereo, simultaneously through my Chatterbox GRMS x1. I wanted to have a volume control for the final mixed audio line- each device has it's own volume control, so I didn't need to build in additional line-in volume controls.
Cash is tight, so I built one.
Devices:
- 1. MP3/CD player
- 2. Valentine 1 warning audio
- 3. Police scanner to keep tabs on the CHP aircraft channels
Components needed:
6 10k 1/4 watt resistors
4 1/8 stereo audio jacks in housings
1 miniature audio Potentiometer, dual gang 1/2 watt
1 knob for Pot
1 small project box 1"x2"x3"
22 gauge wire
Solder
Shrinkwrap
The mixer works well, but has one small problem. Would really appreciate any advice on how I can get more volume out of the unit. It's about a third to a half as loud as any of the individual audio devices. I need a bit more volume to really make it work at speed.
Should I have used lower wattage resistors? IE: 1/8 watt
Would a 1/2 watt 200k Audio Potentiometer be limiting my overall volume?
Here are some project images:
The simple black box- easy to carry, with volume control out and three audio inputs to work with.
The inside circuitry. Shrink wrapped/soldered. About 15 bucks worth of parts, and about two hours of time.
Here's how it works. Only two inputs are shown in this image but there's room for a third, and the audio out actually goes into the headphones in my helmet. I run the Valentine 1 radar detector's audio out into the third input so I can ride fast, listen to ambient funk, hear the CHP aircraft channel chatter, and talk over the GMRS. If I could only get a cup of espresso with that.. :nerd
Here's the simple schematic I found online. I added a third input jack and a stereo potentiometer to control the volume out.
Cheers,
Coop