Who wants to get weird with vocoders and microphones? I DO!!! This seems like hours of stupid fun. Maybe we could build a different easier vocoder and not necessarily this specific one. I just want a vocoder. Who's with me? ===> ===>VOTE HERE===> ===> ===>
The first thing we need is a circuit design, which I am posting as a series of images. I designed it from scratch, although I did investigate as many vocoder schematics I could get my hands on. I focused on using easily obtainable components that are inexpensive, and I tried to keep the circuit as simple as possible without sacrificing functionality.
A vocoder basically has two inputs and one output. The first input is the program (usually a connected to a microphone) and the second input receives a carrier signal (usually a keyboard). The program signal is then fed to an analysis section, which extracts the spectral information from the sound and applies it to the carrier signal. This vocoder will analise the signal on 14 bands, but the design can easily be modified to include more channels, or actually fewer (if you are in a hurry).
First, we must have input amplifiers for each of the two inputs. Then, we must build each channel, and finally mix all the channels. These are the three main blocks of the circuit. All the 14 analysis channels are identical, except for the values of the capacitors (I purposely designed it this way to make it easier to build).
Each channel in the analysis section consists of two identical band pass filters. The first receives the program signal which then goes into an envelope follower. The output of the envelope follower then controlls an VCA (voltage controlled amplifier) which amplifies the carrier signal coming in through the other band pass filter.
The next step contains a parts list, however, I will tell you right away that ALL the op amps in the circuit are TL074. So all the components you will need are the TL074's, resistors, condensers (capacitors), and NPN transistors (2N2222). I am trying to keep it simple. Also, you will obviously need wires, connectors, pots, jacks, and some material to put the whole thing in (I used plywood, MDF, and acrylic for the casing.
This circuit also requires a bipolar power supply (+/- 10-15 volts). I pulled out the power supply from a damaged old computer, which is bipolar, I used the +12v, ground, and -12v from this power supply (they are standardly marked yellow, black, and blue respectively in a computer power supply). Using an existing power supply will save you a lot of time and money.
In this step you should download and study the schematics just to get acquainted with the project.
I have to come clean with you guys… the real reason I want to build a vocoder is because I have always wanted to start a Beach Boys cover band but do it reggae style and do all the vocals with a vocoder. I’m gonna call it “Right Near the Beach Boyeeeeeeeeeees!”.
I have to come clean with you guys… the real reason I want to build a vocoder is because I have always wanted to start a Beach Boys cover band but do it reggae style and do all the vocals with a vocoder. I’m gonna call it “Right Near the Beach Boyeeeeeeeeeees!”.
There is definitely vocoder on the background vocals on this song. My cover band will definitely cover this song even tho its not a beach boys song. It will fit in with the overall DNA of The Right Near The Beach Boyeees. @Feral Feline you will have a 15 minute vocoder bass solo on this song.
<img src="http://cdn.instructables.com/F4O/IPU4/FXK6BXVK/F4OIPU4FXK6BXVK.MEDIUM.gif" alt="analisis.gif"/>
<img src="http://cdn.instructables.com/FV8/VTLH/FXK6BFL5/FV8VTLHFXK6BFL5.MEDIUM.gif" alt="chart.gif"/>
