This is a tutorial aimed at showing C++ programmers how to program their own synthesizer. The example code is written to be as straightforward and minimal as possible and require no external libraries.

• DIY Synth 1: Sound Output
• DIY Synth 2: Common Wave Forms
• DIY Synth 3: Sampling, Mixing, and Band Limited Wave Forms
• DIY Synth: Basic Drum
• DIY Synth: Flange Effect
• DIY Synth: Delay (Echo)
• DIY Synth: Multitap Reverb
• DIY Synth: Convolution Reverb & 1D Discrete Convolution of Audio Samples

Other useful posts:

• Decibels (dB) and Amplitude

I did a presentation at work on audio synthesis for music. Slide deck and real time synthesizer source code can be found at the link below:
Intro To Audio Synthesis For Music Presentation