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Everything Voice AI: from the physics of audio codecs to the architecture of real time streaming pipelines. Written by builders, for builders.

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21 September 2026·8 min read

Personal Data in Call Transcripts: Redaction, Consent and India's DPDP Act

Every customer call can capture names, phone numbers, addresses and identity numbers. With India's Digital Personal Data Protection Act now moving into force, businesses need a clear approach to consent, redaction and retention.

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18 September 2026·8 min read

Retrieval-Augmented Generation Under Real-Time Constraints

Retrieval-augmented generation is the standard way to ground language models in business knowledge. On a live call, every retrieval decision competes with the silence a caller can hear. Here is how the design changes.

Abstract cover of a teal sound wave anchored to a grid of small glowing points, suggesting speech tied to verified factsAI and LLMs
15 September 2026·8 min read

Grounding and Verification: Reducing Hallucinations in Voice Agents

A language model that invents a refund policy in a chat window is a problem. The same mistake spoken aloud on a customer call is worse. Here are the principles for grounding and verifying what a voice agent says.

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12 September 2026·9 min read

Code-Switching and Speech Recognition: The Challenge of Hinglish

Most callers in urban India do not speak pure Hindi or pure English. They mix both, often inside a single sentence. Here is why that breaks conventional speech recognition, and how the field is approaching the problem.

Abstract amber and charcoal cover showing a waveform passing through a grid of scoring marks and distribution curvesEngineering
9 September 2026·9 min read

Evaluating Conversational Voice Agents: Methods and Metrics

A voice agent can pass every unit test and still frustrate real callers. This guide covers component and end-to-end metrics, latency percentiles, simulated callers, LLM judges, audio testing and production experiments.

Abstract cover of digits and currency symbols dissolving into flowing green sound wavesVoice Synthesis
6 September 2026·9 min read

Text Normalisation for Indian Speech Synthesis: Numbers, Currency and Dates

A speech synthesiser cannot read ₹2,50,000, 05/06/2026 or GST without first turning them into words. Text normalisation for Indian languages brings lakhs, irregular Hindi numerals, code-mixing and more.

Abstract illustration of two overlapping sound waves in teal and white, one small and rhythmic, one rising to cut across the otherConversation Science
3 September 2026·9 min read

Backchannels and Barge-In: Managing Interruptions in Voice Conversations

Listeners constantly say hmm, haan and achha while someone else talks. A voice agent must separate these supportive signals from genuine interruptions, and recover gracefully when a caller really does cut in.

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31 August 2026·9 min read

Prompt Injection Through Speech: Securing Voice AI Agents

A voice agent takes instructions in natural language from anyone who dials the number. That makes prompt injection a practical risk, not a theoretical one. This post explains how speech changes the threat and which defences actually hold.

Abstract green letterforms from Devanagari and Gujarati scripts dissolving into a smooth pronunciation waveformLinguistics
28 August 2026·9 min read

Schwa Deletion and Indian Names: The Pronunciation Problem in Speech Synthesis

Hindi spelling hides a vowel that is often not pronounced. For speech synthesis this inherent schwa, along with retroflex consonants, aspiration and romanized names, turns pronunciation into one of the hardest problems in Indian voice AI.

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25 August 2026·9 min read

Writing for the Ear: Prompt Design for Spoken Language Output

Language models learned to write from documents, so their default output is built for the eye: headings, lists, long clauses and parentheticals. A phone caller hears none of that structure. Here is how to prompt for speech instead.

Abstract cover showing a waveform aligned above rows of text fragments, some highlighted in amberSpeech Recognition
22 August 2026·9 min read

Beyond Word Error Rate: Measuring Speech Recognition That Works

Word error rate is the standard metric for speech recognition, yet it can mislead badly for Hindi, Gujarati and code-mixed telephone audio. This post covers normalization, CER, entity accuracy, task success and building test sets you can trust.

Abstract cover showing a line of Devanagari characters breaking apart into many small coloured fragmentsNLP
19 August 2026·9 min read

Token Fertility in Indic Languages: Why Hindi Requires More Tokens Than English

The same sentence can consume far more tokens in Hindi or Gujarati than in English. This post explains subword tokenization, byte-level fallback and UTF-8, and why that imbalance affects context, speed and quality of language models.

Abstract cover showing two interlocking waveforms separated by a narrow band of empty spaceConversation Science
16 August 2026·9 min read

The 200-Millisecond Gap: Turn-Taking in Human and Machine Conversation

Humans take turns in conversation with gaps of roughly a fifth of a second, far faster than they can plan speech from scratch. This post explains how that is possible and why voice agents must learn to predict, not just react.

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13 August 2026·6 min read

Voice AI for Bharat: Why Multilingual Agents Are the Next Big Leap

The next 500 million AI users will not primarily speak English. They will speak Hindi, Tamil, Marathi, Bengali, Telugu, and dozens of other languages. Building Voice AI for this audience requires rethinking assumptions made by Western AI research.

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11 August 2026·5 min read

Text to Speech in 2026: The Race for Zero Latency, Human Quality Voices

Modern neural TTS can clone a voice from 10 seconds of audio and synthesize speech faster than real time. Understanding how TTS systems work, and where they still fall short, is essential for anyone building Voice AI products.

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9 August 2026·6 min read

The LLM Phone Call: How Language Models Are Rewriting Conversations

Putting an LLM on a phone call is harder than it looks. Context windows, conversation memory, function calling for real business actions, and tight latency constraints all collide. Here is how it is done right.

Abstract teal and gold waveform compression visualization with binary dataTechnical
7 August 2026·6 min read

Codecs Demystified: Why G.711 Still Rules the Phone World

Audio codecs are the hidden variable in every Voice AI deployment. They determine fidelity, bandwidth, latency, and ASR accuracy. Whether you are debugging a muffled AI call or optimizing for mobile networks, codec knowledge is essential.

Flowing teal and green waveform streams moving through dark spaceArchitecture
5 August 2026·6 min read

Real Time Streaming Audio: How AI Voice Agents Speak Without Lag

The magic of a natural AI voice conversation comes down to latency. Understanding how streaming audio pipelines work, from audio capture to TTS playback, reveals the engineering beneath what feels like a simple phone call.

Golden fiber optic telephone network nodes glowing in dark spaceTelephony
3 August 2026·6 min read

SIP, PSTN and the Phone Stack: What AI Voice Agents Actually Dial Into

Before an AI agent says a single word, its audio has to travel through a web of protocols and switches that date back to the 1950s. Understanding the PSTN, SIP, and the full telephony stack is essential for anyone building reliable Voice AI at scale.

Glowing teal waveform bars visualizing voice activity detectionDeep Dive
1 August 2026·7 min read

Voice Activity Detection: The Silent Engine Behind Every AI Call

Voice Activity Detection is the invisible gatekeeper of every AI voice conversation. Without it, AI agents would talk over you, process silence as speech, and rack up unnecessary compute costs. Here is how it actually works.

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