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Indic Voice Collection Where Each Language Gets Its Own Design

TLDR If you ship voice for India, a language label is not coverage. You need speakers who match your users, sessions that match your product, and transcripts you can train on without cleanup.

At posterior.xyz we collect speech in English, Hindi, Kannada, Telugu, Tamil, Malayalam, Marathi, and Sanskrit, plus more on request. Each language gets its own plan. That is the whole point.

Why does one plan never fit all Indian languages?

Hindi code-switching in Delhi sounds nothing like Tamil spoken in Madurai. Reading fluency in Mumbai looks nothing like spontaneous speech from a first-time smartphone user in Kochi.

So we never copy a speaker grid from one language to another. You tell us who uses your product. We build a separate collection design for each language around that reality.

What goes into a speaker matrix?

Before we record anything, you review a speaker matrix per language.

Typical dimensions include

  • Region and mother tongue influence within the language
  • Age bands and gender balance tied to your user base
  • Device familiarity
  • Reading fluency versus spontaneous speaking style
  • Recording setting, with studio control or field realism or a mix of both

You sign off on the matrix. Then recruiting starts. What ships later traces back to that sheet, so your eval reflects deployment instead of convenience sampling.

This part is kinda unglamorous and it decides everything. Get the matrix right and the model has a chance. Get it wrong and no amount of tuning saves you.

Which task designs match your deployment?

A voice assistant breaks in different places than an IVR flow. We shape prompts and sessions around your failure points.

Task typeWhat we recordGood for
Scripted promptsPhonetically balanced sentences and controlled vocabularyASR coverage and pronunciation
Conversational tasksFree talk with turn taking, pauses, repairs, and interruptionsAssistants and agents that hold a conversation
Channel separated recordingsMulti speaker sessions with clean per speaker tracksDiarization and meeting transcription
Wake word and commandsVaried phrasing at different distances and noise levelsDetection with fewer false accepts
IVR style flowsMenu paths with confirmations, corrections, and retriesCall automation that survives real callers

Each session ships with structure notes on mic setup, session length, and prompt order, so you can split train and test the way you want.

How is tone kept intact in translation?

Parallel prompts across languages need more than literal word swaps. A polite request in Marathi can sound flat or abrupt when moved word for word into Hindi, and your model picks up the wrong habit.

You send source prompts with desired formality. Native reviewers adapt phrasing so politeness, urgency, and natural phrasing carry over. Where reviewers disagree, we flag the choice for you instead of smoothing it over. You receive source text and adapted text side by side, so you can audit every call.

Who sets the transcription rules?

Transcript noise looks like model error. We fix that by agreeing on rules before annotation starts.

You set conventions for

  • Code switching and borrowed words heard in daily speech
  • Fillers, repetitions, and partial words
  • Numerals, punctuation, and product terms
  • Addresses and named entities
  • Unintelligible spans and overlapping speech

We train annotators on your guide, check adherence in sampling rounds, and version the guide. When you change a rule, we reprocess affected files to the new version and note what changed.

Exhibits from our collection

Exhibit 1 — Scripted Hindi take from its own speaker matrix: region, age band, and recording setting logged per file.
Exhibit 2 — Scripted Telugu take from a separate matrix. Each language recruits its own speakers; grids are never copied across languages.

Target-side delivery for translation — task reference, language, and adapted line stay linked:

task: translation-2-mr | language: Marathi
इथे जवळचे दुकान कुठे आहे ?

Exhibit 3 — Native-reviewed Marathi adaptation with politeness intact. Source and adapted text ship side by side so you can audit every call.

Common questions

Which languages do you cover now?

English, Hindi, Kannada, Telugu, Tamil, Malayalam, Marathi, and Sanskrit. We add more on request when you bring the speaker definition.

Can you mix studio and field audio?

Yes. Many teams use studio takes for baseline coverage and field takes for noise tolerance. You set the ratio per language.

Do you support audio plus video?

Yes. The default pipeline is audio only. When your product needs face or gesture context, we add synced video with the same speaker matrix.

How does licensing work?

You get rights scoped to model training and evaluation. We confirm consent, payment, and usage terms per speaker before delivery.

Start with a paid pilot

Send us your speaker matrix and three sample tasks. We record a small set, transcribe to your conventions, and deliver files you can train on. Both sides check fit before scaling.

Request a pilot or Talk to us.

Pair with studio versus field audio and text annotation to your taxonomy.

Sources

  • OpenAI Whisper — the transcription engine behind our speech first-pass drafts, which humans then correct to your conventions.
  • First-hand: process claims above describe our own pipeline — per-language speaker matrices, task designs, and tone-preserving translation review. The exhibits are verbatim outputs — real takes and a real delivery line — not illustrations.
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