Browser-based audio processing has crossed a threshold. A few years ago, applying reverb or delay online meant a janky web app with limited controls and unacceptable latency. Today, the Web Audio API gives modern browsers the signal processing horsepower to run studio-grade effects in real time — entirely client-side, with no plugins, no downloads, and no cloud processing involved.

The Radio FX processor at djmixer.online puts 14 audio effects and 12 presets in your browser. This guide covers every effect, every preset, and how to use them for real work — from processing radio streams to DJ mixing to audio experimentation.

The Effects Rack: All 14 Effects

Each effect can be enabled and disabled independently. Stack as many as you want in the processing chain. Here is what each one does:

Filter
A standard high-pass or low-pass filter that rolls off frequencies above or below an adjustable cutoff. The most direct way to thin or darken a sound.
Moog Filter
A resonant filter modeled on the iconic Moog ladder circuit. Adds a distinctive analog-style self-resonance at the cutoff frequency — more musical and characterful than a plain filter.
WahWah
An auto-wah that sweeps a bandpass filter across the frequency spectrum rhythmically. Adds a vocal, funky quality to any audio. Rooted in guitar effects but powerful on electronic music too.
Overdrive
Soft-clips the audio signal to introduce harmonic distortion. Ranges from a subtle warm saturation at low drive settings to aggressive distortion at high settings.
Bitcrusher
Reduces the bit depth and sample rate of the audio, producing lo-fi digital artifacts and grit. A key tool for industrial, glitch, and lo-fi aesthetics.
Compressor
Reduces dynamic range by attenuating loud peaks and boosting quieter passages. Makes the output more consistent in level. Essential for broadcast processing and heavy mixes.
Delay
Repeats the audio signal after a set time interval. Creates echo effects that range from subtle slapback doubling (short delay) to full rhythmic echo patterns (longer delay with feedback).
Ping-Pong Delay
A stereo delay that alternates repeats between the left and right channels. Creates a wide, bouncing echo effect. Highly effective on headphones and stereo speakers.
Chorus
Layers multiple pitch-modulated copies of the signal to create a thick, shimmering texture. Adds width and richness, mimicking the sound of multiple instruments playing together.
Phaser
Passes the signal through all-pass filters set at different frequencies, then mixes it back with the dry signal. Creates a sweeping, notched effect as the phase relationships cycle — the classic psychedelic sound.
Tremolo
Modulates the volume of the signal at a set rate. Ranges from a subtle pulsing to choppy rhythmic gating depending on depth and speed settings.
Reverb (Convolver)
Applies a convolution reverb that simulates placing the audio inside a real acoustic space. The result is richer and more natural than algorithmic reverb — the audio sounds like it was recorded in a room, hall, or cathedral.
Cabinet
A speaker cabinet impulse response that simulates the frequency coloration of a guitar or bass cabinet. Adds warmth and natural roll-off, especially effective on distorted or overdrive-processed audio.
Panner
Moves the audio between the left and right channels. Ranges from full mono to wide stereo spread. Useful for creating space in a mix or correcting center-heavy audio.

12 Built-In Presets

Rather than configuring the effects chain from scratch, you can load any of the 12 presets. Each preset activates a specific combination of effects tuned for a particular sound or context:

Deep Space
Lofi Radio
Club Compress
Dub Echo
Psychedelic
Warm Tape
Crystal Hall
Bit Grunge
Vintage Filter
Wide Stereo
Dark Tunnel
Acid Bass

Presets are a starting point, not a final destination. Load any preset, then adjust individual effect parameters to dial it to your exact taste. You can also add or remove effects from a preset chain to create something entirely custom.

Reverb Online: What the Convolver Effect Does

Reverb is the most-searched audio effect for good reason. It transforms any audio by placing it in a simulated acoustic space. A dry, close-mic'd vocal sounds isolated; the same vocal with reverb sounds like it exists in a room with you.

The convolver reverb in the Radio FX processor uses impulse response convolution — the same method used in professional studio reverb plugins. An impulse response is a recording of a real acoustic space's echo pattern. The convolver applies that pattern to the incoming audio in real time.

How reverb online differs from hardware: Traditional hardware reverb uses spring or plate reverb circuits. Browser-based convolution reverb uses actual recordings of physical spaces, which is technically a more accurate simulation. The Web Audio API handles this efficiently enough to run without any perceptible latency in modern browsers.

For DJ mixing, reverb is most effective as a transition tool. Apply it heavily to the tail end of the outgoing track — the audio dissolves into the space rather than stopping abruptly. Bring in the incoming track while the reverb tail fades. The result feels like one continuous moment rather than a cut.

Echo Effect Online: Using Delay and Ping-Pong

Echo and delay are used interchangeably by most people, and the distinction matters. A delay effect produces discrete, separated repeats — you hear the original sound, then a repeat after a set time interval, then possibly another repeat, decreasing in volume. The "echo effect" most people imagine is this: a sound that bounces back after a noticeable gap.

The Ping-Pong Delay variant adds a stereo dimension: the repeats alternate between left and right channels. On headphones, this creates a dramatic sense of space. On speakers, it adds width and movement that a mono delay cannot achieve.

Both the standard Delay and Ping-Pong Delay are available in the Radio FX effects chain. Use Delay for a classic echo effect on any audio stream. Use Ping-Pong for maximum stereo impact, especially effective on melodic loops and vocal phrases.

Technical Foundation: Web Audio API + Tuna.js

The Radio FX processor is built on the Web Audio API, the browser-native audio processing system available in all modern browsers. The Web Audio API provides low-level audio nodes — filters, gains, delays, analysers, convolutors — that can be wired together into an arbitrary signal processing graph.

On top of the native Web Audio API nodes, the effects processing uses Tuna.js, an open-source audio effects library that implements the more complex algorithms: the Moog filter model, the convolution reverb, the chorus and phaser modulation. This combination gives access to studio-quality effects without any server-side processing — everything runs entirely in your browser, on your device.

This has an important privacy implication: your audio never leaves your device. No stream is uploaded to a server. No data is collected. The 3-band EQ, all 14 effects, and all 12 presets process audio locally in real time.

Use Cases: What to Do with 14 Online Audio Effects

Process a Radio Stream

Route any audio source through the Radio FX processor and apply any combination of effects in real time. Load the "Club Compress" preset for a broadcast-style loudness treatment, or "Lofi Radio" for a vintage degraded sound. Effects apply to the live stream — not to a recording.

Apply Effects to Any Audio File

Load a local audio file through the browser and run it through the effects chain. Test how different effect combinations change the character of a track. The output plays through your speakers or headphones with the effects applied live.

DJ Mixing Transitions

The Delay effect paired with the 3-band EQ creates the professional "echo out" transition: apply delay to the outgoing track's tail, cut the low EQ on it while the echoes fade, and bring in the incoming track underneath. This is the technique used in dub and deep house DJing. See the transition techniques guide for the full sequence.

Experimentation and Sound Design

Stack unexpected combinations: Bitcrusher into Convolver creates a gritty, spatial wash. Overdrive into Cabinet gives a warm, saturated push with speaker coloration. WahWah into Ping-Pong Delay creates rhythmic, wide movement. The effects chain has no limitations on what you combine.

How to Access All 14 Audio Effects

  1. Go to djmixer.online/mixer/radio/
  2. Click any preset card to load it — effects activate immediately
  3. Toggle individual effects on or off with their enable buttons
  4. Adjust the parameter knobs on each active effect
  5. Use the 3-band EQ (Low/Mid/High with kill switches) in parallel

All effects are free. No account required. Audio stays on your device. For frequency analysis before and after processing, use the TuneLab audio tools to inspect the spectral content of your processed audio.

For a deeper understanding of the EQ section specifically, see the online equalizer guide, which covers the 3-band EQ in detail, including the bass swap technique for DJ mixing.