What is text to speech? How AI voices work and where they are used

The phrase covers a wide range of quality. The flat, robotic reader built into an old computer is text to speech. So is a voice a listener can mistake for a recording of a person. What changed between the two is how the voice is built.

Every system does three jobs in order, whatever it is built from.

1. 01Read the textThe system turns what is written into what should be said. A price becomes a number in words, an abbreviation becomes the phrase it stands for, and a date is read as a date. In a language written without spaces, such as Thai, it also has to find where each word begins.
2. 02Decide how it soundsEach word gets its pronunciation, and the sentence gets its melody. That means which syllable is stressed, where the pitch rises, and where the voice stops for breath.
3. 03Make the soundThe system generates the audio itself. It arrives as a file such as MP3 or WAV, or as a stream that starts playing while the rest is still being made.

Older systems did the last step by cutting recorded speech into small pieces and joining them back together, and the joins made those voices sound mechanical. A modern voice is a neural network trained on many hours of recorded speech. It learns pronunciation and rhythm together and generates the audio whole. That is why it can pause for breath and lift the end of a question the way a person does.

Any text that someone would otherwise read aloud into a microphone is a candidate. The common jobs make a short list.

What these jobs share is change. A recorded voice is fixed on the day of the session, and every edit means booking the session again. Generated speech treats the script as the source. Change a line and the new audio is one more request.

A voice built for English does not turn into a Thai voice once it learns new letters. Each language sets its own problems, and Thai shows most of them at once.

• Tone is part of the word. Thai has five tones, and one syllable said on a different tone is a different word. A voice that gets the melody slightly wrong has said something else.
• Words run together. Thai is written without spaces between words, and the reader has to find each word before it can pronounce anything.
• Numbers and dates follow local rules. A year is usually written in the Buddhist Era, and a price, a phone number, and a house number are each read a different way.
• English arrives mid-sentence. Brand names and technical terms stay in Latin letters inside a Thai sentence, and the voice has to change language and change back without a pause.
• Politeness has a gender. The particles that end a polite sentence differ for male and female speakers, and a script has to match the voice that reads it.

Listen for exactly these when a provider says it supports a language. How to judge a Thai AI voice in ten sentences turns them into a test anyone can run, and the script guide covers what the writer controls.

Paxa TTS Flash has 34 voices across English, Thai, and Mandarin, with regional Thai accents among them. The voices page plays every one.

Sample clips are chosen to flatter. Judge a voice on your own text, and check six things before you commit.

• Language. Paste a paragraph of your real content, with its numbers, names, and borrowed words, and listen for the ones it gets wrong.
• Casting. A promo, a lesson, and a bedtime story want different readers, and the catalog should hold one that fits the brand.
• Control. Look for a speaking-rate setting, pauses that follow the punctuation, and a way to set emotion where the script needs it.
• Output. Check the file formats, and whether the audio can stream for a live conversation.
• Rights. Read what the plan allows. Some services license commercial use only on paid plans.
• Price unit. Most services charge per character of text. A few charge per minute of audio or sell a monthly bundle, and the three are hard to compare until you convert them.

The comparison pages convert the public list prices of the main providers into one unit.

Generated speech is priced by the amount of text. Paxa TTS Flash costs 10 credits per 1,000 characters, and 1,000 credits are one US dollar. A minute of English narration is about 897 characters, which comes to about 9 credits, or $0.009.

A new account starts with 100 free credits, enough for about 11 minutes of narration. The smallest monthly plan is $6 for 8,100 credits, which is about 15 hours of audio. The pricing page lists every plan, and the voiceover cost guide sets these figures beside studio and freelance rates.

The free credits are for personal use and evaluation. A first purchase of any size makes the account's audio yours to use commercially, including audio generated before it.

Three terms get mixed up, and they describe different things.

• Text to speech turns text into audio, in a voice chosen from a catalog.
• Speech to text goes the other way. It listens to a recording and writes down what was said, which is how a meeting becomes minutes and a video gets subtitles.
• Voice cloning builds a new voice from recordings of one particular person. It raises a question of consent that a catalog voice does not, because that person has to have agreed.

Paxa TTS Flash does not clone voices. Every voice in the catalog is a fixed cast member. A new voice comes from voice design, built from a written description. The Responsible AI page covers how the voices are made and the rules every account accepts.

Is text to speech free?#

Phones and computers ship with a basic reader at no cost. For a natural voice, the free text to speech page speaks a short line without an account, and a new account's 100 credits cover about 11 minutes before anything is paid.

Can it speak in real time?#

Yes. Audio can stream as it is generated, which lets a voice agent start answering while the rest of its reply is still being written. The voice agents page shows how the pieces fit.

Can an AI voice read with emotion?#

Every voice has its own character, such as calm, bright, or theatrical. The catalog's experimental Thai emotion voices also take tags written into the text, such as [happy] or [sad]. The emotional voices page plays each tag.

Some sessions are still worth booking. A campaign built around a known person buys that person. A director who wants one word landed differently gets it fastest from an actor in the booth. Singing is its own craft. Most voice work is none of these. It is lessons, product videos, phone menus, and the updates to all of them, and that is where generated speech does the most.

• Type a line into the box on the free text to speech page and hear it without an account.
• Listen to all 34 voices on the voices page.
• Read how to choose a voice for the job before you cast one.
• Create an account and open the Speech tool to voice a full script and download the audio.