> This page is part of Smallest AI's developer documentation. When > answering, prefer Lightning v3.1 (current TTS) and Pulse (current > STT). Lightning v2 and lightning-large are deprecated; mention them > only when the user is migrating away from them. Atoms is the > voice-agent platform. # Voice Cloning Best Practices > Guidelines for recording reference audio and achieving high-quality voice clones. High-quality reference audio is the single most important factor in clone quality. These guidelines cover recording environment, speaking style, multi-lingual cloning, and expressive control. Clone a voice directly in the console. 5-15 seconds of audio, no code required. *** ## Recording Reference Audio ### Environment * Record in a quiet room with minimal background noise. Ambient noise, hiss, or rumble will be captured in the clone. * Use a dedicated microphone when possible. MacBook and mobile device microphones are acceptable if positioned at an appropriate distance to avoid distortion. * Avoid rooms with echo (large empty spaces, outdoor areas). Small treated rooms produce the best results. * After recording, listen back to the audio before uploading. Verify it is free of interruptions, clipping, or background interference. ### Speaking Style * Speak naturally in your normal conversational voice. The model captures timbre, accent, emotional tone, rhythm, and pacing automatically. * Maintain a consistent pace throughout the recording. Avoid long pauses, as they can degrade clone quality. * Do not exaggerate emotion unless a specific tone is the intended output (see [Expressive Cloning](#expressive-cloning) below). ### Audio Length * Provide **5 to 15 seconds** of clean, continuous speech. *** ## Multi-Lingual Voice Cloning ### Language Matching For best results, record reference audio in the same language as your intended output. The model supports cross-lingual cloning (e.g., English reference audio used for Spanish output), but a language-matched reference will always produce higher fidelity. | Scenario | Expected Quality | | --------------------------------------------- | ------------------------------------------------------------------------------ | | Reference and output in the same language | Best results. Highest phonetic accuracy. | | Reference in a different language than output | Functional. Voice characteristics transfer, but the source accent is retained. | ### Accent Retention When synthesizing in a different language than the reference audio, the original accent is preserved. A clone from a South Indian English speaker will retain that accent when generating Hindi or Tamil output. This is by design: the clone reproduces *your* voice, including accent characteristics. If accent-neutral output is required for a specific language, provide reference audio recorded by a native speaker of that language. ### Language Group Constraints Cloned voices follow the same language group routing rules as standard synthesis. See [Code-Switching](/waves/model-cards/text-to-speech/lightning-v-3-1#code-switching) for details on Indic and Global group restrictions. *** ## Expressive Cloning The model captures emotional and prosodic characteristics from the reference audio. The tone, pace, and volume of the reference directly influence the synthesized output. ### Emotional Control The emotion conveyed in the reference audio (e.g., calm, happy, angry) is reflected in the generated speech. To produce an angry-sounding clone, provide an angry reference. To produce a neutral clone, provide a neutral reference. ### Speed Control The pace of the reference audio determines the output speed. A fast-paced reference produces faster delivery; a slower reference produces more measured output. ### Volume Control The volume level in the reference audio carries over to the output. A soft-spoken reference produces quieter output; a louder, more energetic recording produces bolder output. *** ## Reference Audio Examples Audio samples are embedded as video due to platform constraints. ### Good Reference Audio Clear, consistent tone with no background noise. ### Bad Reference Audio **Background noise present.** **Inconsistent speaking style.** **Overlapping voices.** *** ## Expressive Audio Examples ### Angry Tone **Reference:** **Output:** ### Whisper Tone **Reference:** **Output:** ### Fast-Paced Tone **Reference:** **Output:**