Building my first audio plugin with JUCE

After years of tweaking knobs on other people's plugins, I finally decided to build my own. The idea had been bouncing around in my head for a while: a simple tube saturation plugin that actually sounded warm without being muddy.

Why JUCE?

If you're getting into audio plugin development, JUCE is basically the industry standard. It handles all the cross-platform nastiness (VST, AU, AAX) so you can focus on the actual DSP. The learning curve is real, but the documentation is solid and there's a great community.

void WarmTubeProcessor::processBlock(AudioBuffer<float>& buffer, MidiBuffer&)
{
    for (int channel = 0; channel < buffer.getNumChannels(); ++channel)
    {
        auto* channelData = buffer.getWritePointer(channel);

        for (int sample = 0; sample < buffer.getNumSamples(); ++sample)
        {
            // Soft clipping with tube-style saturation
            float x = channelData[sample] * driveAmount;
            channelData[sample] = std::tanh(x) * outputGain;
        }
    }
}

The basic idea behind tube saturation is soft clipping. When you push a tube amp, it doesn't just cut off the signal harshly—it rounds it off smoothly, adding harmonics that our ears perceive as "warmth."

The DSP rabbit hole

What started as a simple tanh() waveshaper quickly became an obsession with modeling the actual behavior of vacuum tubes. Turns out there's a reason companies charge $200 for good saturation plugins—the math gets complex fast.

Key things I learned:

  1. Oversampling is essential - Without it, you get nasty aliasing artifacts
  2. Filters matter - Pre and post filtering shape the character dramatically
  3. UI is half the battle - A good-looking plugin inspires creativity

What's next

I'm currently working on adding a proper EQ section and maybe some bias controls for more tonal options. The goal is to release it as a free plugin once it's polished enough.

If you're thinking about building your own plugins, I'd say go for it. The combination of music and code is incredibly satisfying, and there's nothing quite like hearing your own DSP in a mix.