SpellSynth Manual
Type a word on the keypad — or tap TYPE to use your keyboard.
Tap ▶ SAY to hear it spoken aloud.
Open Settings (⚙) and pick a vintage voice.
1 · The basics
SpellSynth looks like a pocket spelling toy. The green VFD display at the top shows what you type and what it's saying. Below it is the A–Z keypad with a ⟵ delete key and (in Free Play) a SPACE key. The MODE bar switches between the five modes, and the gear (⚙) opens Settings, where you choose your voice and replay the tutorial. A RECENT row remembers what you've played this session — tap a chip to hear it again.
2 · Free Play — words, phrases & numbers
Free Play is the heart of SpellSynth: type anything and hear it spoken back. It now handles single words and whole phrases.
Typing
Use the on-screen keypad, or tap TYPE to switch to your device keyboard (handy for punctuation or longer text). Tap SPACE between words to build a phrase.
Speaking it
Tap ▶ SAY. A single word plays straight through; a phrase is read word-by-word, and the display cycles to each word as it plays.
Numbers & contractions
Numbers are spoken as words — "I have 2 cats" says "two". Contractions are kept intact, so "don't" and "we'll" sound right instead of being spelled out.
GAP, SHARE & RECENT
The GAP slider tunes the pause between words from 50 to 500 ms. SHARE renders the current word or phrase to a 16-bit / 24 kHz WAV you can save or drop into a DAW. Everything you play lands in the RECENT row for one-tap replay.
3 · SEQ — the word step sequencer new in 1.3.0
SEQ turns SpellSynth into an instrument you can play in time. Sixteen steps, each holding a word that speaks in your chosen voice.
Filling the grid
Tap a step and type what it should say, then tap DONE. Two or more letters is a word. A single letter is treated as a letter and uses the recorded alphabet voice — so you can spell a word out across several steps and then say it whole on the next one. Leave a step empty for a rest.
Playing it
Tap ▶ PLAY. The display shows each word as it fires and the grid highlights the step you're on. CLEAR empties the grid.
Tempo and feel
BPM runs from 40 to 240. Steps land on 1/4, 1/8 or 1/16 notes, and the loop can be any length up to 16 steps. FIT stretches each word to exactly fill its step — with it on, words speed up and pitch up as you push the tempo, the way a sampler does. With it off, each word plays at its natural speed and the next step cuts it off.
In your DAW
The AUv3 has the same sequencer, following your host's tempo and transport instead of the built-in clock. Two factory presets show both halves of the idea: Robot Chant puts a word on every step, Spelling Bee spells a word out and then says it. Words you have played at least once in the app become available to the plug-in; a word it cannot find shows a ⚠ badge on that step rather than failing silently.
4 · Spell · Mystery · Say It
Spell
SpellSynth says a word — you spell it on the keypad. Three mistakes and it reveals the answer, then moves to a new word.
Mystery Word
The classic hidden-word game. Pick letters until the word reveals itself; six wrong guesses ends the round.
Say It
Listen-and-repeat practice. Hear the word spelled letter by letter, then say it aloud. Great for pronunciation.
Mystery and Say It draw from the built-in dictionary plus any custom words you add, which stay on your device.
5 · The four voices
Pick a voice in Settings. Each is applied to every word you hear — bundled or live-typed — and cached separately, so switching is instant after the first play.
Default
Clean system speech with no retro processing — for when you just want clear pronunciation.
1968 Odyssey
Deep-baritone monotone with a slow, deliberate cadence. A nod to late-60s sci-fi computer voices.
1978 LPC
The original Speak & Spell character — a 10-pole LPC vocoder driven by the actual TMS5220 chirp. Buzzy and unmistakable. Cleaned up in 1.2.6 for even loudness and no glitches.
1986 DECtalk Style
Fixed-pitch impulse synthesis, modelled on the Klatt-style voice that defined Hawking's computer. Deliberate and emphatically computery.
Any word beyond the 500+ bundled words falls back to on-device speech, routed through your chosen voice and cached to disk. Nothing leaves your device.
6 · Tips for parents & classrooms
- Type this week's spelling list into Free Play and let kids hear each word.
- Add custom words for Mystery and Say It — they persist on the device.
- Fully offline after install: no account, no ads, no data collected, nothing links out to the browser.
7 · The AUv3 instrument for musicians
SpellSynth doubles as an AUv3 instrument — the same voice engine inside any Audio Unit host.
Loading it
Open a host on your iPhone or iPad (GarageBand, AUM, Loopy Pro, Cubasis, Logic Pro for iPad), add an instrument track, choose AUv3 Instrument, and pick SpellSynth. The extension is an iOS Audio Unit, so it does not appear in Mac versions of GarageBand or Logic.
Library vs Letters
A LIBRARY / LETTERS switch chooses behaviour. In Library, a text field plays any word as a single retro sample (unknown words fall back to spelling). In Letters, the A–Z keypad plays one letter per tap.
MIDI
Note On/Off with three velocity curves, pitch-bend up to ±12 semitones, sustain (CC 64), and aftertouch routable to any parameter. 14 MIDI-Learn targets save with the preset. The Letter Map plays A–Z on notes 60–85, so you can sequence spelling in your DAW, and the Stutter syncs to host tempo.
Presets & parameters
Ten factory presets — Default, Robot Voice, Tape Warp, Telephone, Tempo Stutter, Classic 1978, Hawking 1986, Odyssey 1968, Robot Chant, Spelling Bee — plus your own via the host. 23 parameters cover pitch, speed, bit-crush, sample-rate, filter, envelope, LFO, stutter, the step sequencer and voice character.
8 · Help & troubleshooting
No sound?
Check the ring/silent switch isn't on silent and the volume is up. If another audio app is active, restart SpellSynth.
Your version
Open Settings (⚙) — the build is shown at the bottom. This manual covers v1.3.0.
Still stuck, or have an idea? See the Support & FAQ page or email zhiii0x@gmail.com.