Voice Data for AI Model Training — Professional Collection & Datasets

Voice data is the raw material of artificial intelligence systems that process, recognise and synthesise human speech. The quality of an automatic speech recognition model, a text to speech system or a voice-enabled virtual assistant depends directly on the quality, diversity and annotation rigour of the data it was trained on. Without good data, there is no good model.
At Voices & Media Solutions, we supply voice data to technology companies, artificial intelligence startups and research teams developing or improving vocal processing systems. Our unique position in the Portuguese language market — with coverage of Portugal, Brazil, Angola, Cape Verde and Mozambique — makes us a difficult partner to replace for those who need data representative of Portuguese variants. We also work with native voices across more than 70 languages.

What is Voice Data and What is it Used For

Voice data consists of sets of human speech recordings that are organised, transcribed and annotated for use in training artificial intelligence models. These are not random recordings or low-quality captures. A voice dataset usable for AI training must meet a rigorous set of technical and linguistic criteria: controlled audio quality, voice diversity, coverage of speech contexts and styles, accurate transcriptions and annotations that enable the model to learn relevant patterns.
This data feeds three main categories of systems: automatic speech recognition, which converts speech to text; voice synthesis, which converts text to speech; and spoken language understanding models, which interpret the meaning of what is said. Each of these applications has specific requirements in terms of the type of data needed.

The Voice Data Service We Provide

Our service focuses on Custom voice data collection. When a client needs data with specific characteristics, we manage the entire process: defining the required speaker profiles, creating reading scripts or spontaneous speech scenarios, conducting recording sessions under controlled conditions, and transcribing and annotating the material produced.
Custom collection is the right solution when a project requires a precise demographic profile, a specific accent, a particular subject domain or a volume of data not available from other sources. It is a more time-intensive process than accessing pre-existing datasets, but it guarantees data fully aligned with the requirements of the model to be trained.

Our Advantage in the Portuguese Language

Portuguese is the fifth most spoken language in the world, with over 260 million native speakers across three continents. Yet in the context of voice data for AI, it remains an under-represented language — particularly in its African variants. Most available datasets cover European Portuguese or Brazilian Portuguese reasonably well. Representative data for Angolan, Cape Verdean or Mozambican Portuguese is scarce.
Voices & Media Solutions has the capacity to supply voice data across all major Portuguese variants: European, Brazilian, Angolan, Cape Verdean and Mozambican. This coverage results from years of work with native speakers from each region and a network of voice professionals across Portuguese-speaking countries. For companies developing speech recognition or voice synthesis systems in Portuguese, this coverage is a critical resource.

Quality Standards in the Data We Supply

The quality of a voice dataset is not measured solely by the number of hours recorded. The criteria that determine the real utility of data for AI model training include:

Audio quality: recordings in acoustically controlled environments, with professional equipment and without background noise that could compromise signal clarity.
Speaker diversity: coverage of different genders, age ranges, regional accents and speech profiles to ensure model robustness.
Context coverage: data representing different speech styles — from text reading to spontaneous and conversational speech — according to model requirements.
Rigorous transcriptions: text aligned with audio at word or phoneme level, depending on the level of detail required.
Relevant annotations: metadata on the speaker, recording context, speech style and other variables that enhance the dataset's training value.

Applications of Voice Data

The voice data we supply is used across a wide variety of projects:

Training automatic speech recognition models for virtual assistants, automatic transcription and voice interfaces.
Development of voice synthesis and text to speech systems with improved naturalness.
Academic and scientific research in computational linguistics and natural language processing.
Evaluation and benchmarking of existing voice models.
Improvement of models already in production with additional data targeting specific performance gaps.

How We Work: From Brief to Delivery

Every voice data project begins with a technical conversation. We need to understand the model the client intends to train, the languages and variants required, the volume of data needed, the level of annotation required and the available timeline. With that information, we present a proposal with the most suitable options.

Technical brief: definition of dataset requirements in terms of language, speaker profile, volume, delivery format and annotation level.
Proposal and validation: presentation of the recommended solution, with volume, timeline and cost estimates. For Custom collection, this includes the speaker profiles and proposed scripts.
Production or curation: Custom data collection or selection and preparation of existing datasets, with transcription and annotation to specification.
Quality control: review of produced material prior to delivery, including audio quality verification, transcription accuracy and annotation completeness.
Delivery: supply of data in agreed formats, with technical dataset documentation and support for integration into the client's training pipeline.

Do You Need Voice Data for Your AI Project?

Every project has different requirements. Some need volume. Others need linguistic specificity. Others need both. Our technical team is available to assess what you need and recommend the most efficient approach — whether Custom collection, access to existing datasets or a combination of both.

Clients