What is TTS: text-to-speech in plain words, how it differs from a recorded voice and its role in AI calls
Sado AI team · · 4 min read
In short
TTS (text-to-speech) is technology that reads written text aloud in a synthetic voice; it’s also called speech synthesis. Unlike a voice recorded in a studio, TTS says any new text on the spot, for example each customer’s own name and order total. On the phone, good TTS reads numbers, dates and prices correctly, with natural stress and pauses. In an AI voice operator, TTS is the last link of the chain: it turns the operator’s answer into the voice the caller hears.
How TTS works
- The text is prepared: numbers become words (“9,800,000” — “nine million eight hundred thousand”), abbreviations are expanded (“sq m” — “square metres”).
- Pronunciation, stress and intonation are set: the voice rises in a question and falls at the end of a sentence.
- A voice model turns that text into sound: a female or male voice, at the right pace.
- The finished audio goes into the phone line and the caller hears it.
A recorded voice vs TTS
| Studio recording | TTS | |
|---|---|---|
| Text | Recorded in advance, fixed | Any new text |
| Name and amount | Can’t be said, or pieces are stitched together | Each customer hears their own |
| Changes | The voice actor records again | Just change the text |
| Where it’s used | IVR menus, autodialers | AI operators, reminder calls |
| What to watch | Outdated prices and offers | Reading numbers and names correctly |
A recording only says a sentence known in advance, so it can’t hold a conversation (what is IVR, autodialer or AI operator). TTS voices a new answer every time.
Example: a housing complex in Yashnabad
The price list of Nur Bog‘ Residence (name invented) has a line like this: “1-room, 52 sq m, 9.8 mln so‘m/sq m, down payment 30%”. If the voice reads it badly, the caller hears “sq m” letter by letter or “nine point eight”, and trust drops. Read correctly, the call sounds like this (prices as an example):
Sado: Assalomu alaykum, Nur Bog‘ Residence, this is Shohruh.
Caller: Hello. How much are the one-room flats?
Sado: One-room flats start from fifty-two square metres, at nine million eight hundred thousand so‘m per square metre. The down payment starts at thirty per cent.
Caller: Can I come and see one on Saturday?
Sado: Yes. I’ll book you a viewing on Saturday at eleven. May I have your name?
Caller: Sardor.
On real estate calls: AI operator for real estate.
What makes a voice sound natural on the phone
- Stress and intonation: a question sounds like a question, an answer like an answer.
- Pauses: a short breath at commas and full stops, long sentences split up.
- Pace: on the phone, slightly slower speech is easier to follow.
- Numbers, dates, prices and phone numbers read correctly.
- Names of people, the company and products said correctly.
- When the caller interrupts, the voice stops and listens.
Listen to a voice over the phone, not through computer speakers, with your own prices, address and company name. That is exactly where callers hear the mistakes.
TTS’s role in an AI operator
An AI operator isn’t TTS itself but the whole chain. The caller speaks, speech becomes text (what is ASR), the operator works out the meaning, builds the answer from your company’s information, and TTS says it aloud. If the caller interrupts, the operator stops and listens.
Sado, an Uzbek-speaking AI operator, speaks Uzbek and Russian. There are two voices: Malika (female) and Shohruh (male). Listen to them on the home page or call 78 778 01 23. More: an Uzbek and Russian voice operator. Other questions: questions about Sado.
Questions
What is the difference between TTS and a voice recording?
A recording is exact text read in advance by a voice actor, and it never changes. TTS voices any new text on the spot, which is why conversations use it.
Can TTS speak Uzbek naturally?
Uzbek TTS voices exist, but quality varies, especially on numbers, prices and names. Listen to the voice over a phone line, with your own prices and names.
Which voices does Sado use?
Two: Malika (female) and Shohruh (male), in Uzbek and Russian. You choose the voice for your company, and the operator speaks in your company’s name.
Will callers know they are talking to AI?
If a caller asks “are you a robot?”, Sado never pretends to be human: it says it is the company’s voice assistant and carries on. You can also switch on a line at the start saying the call is recorded.