Speech-to-Text: which model(s) to choose for analyzing your conversations?

What is Speech-to-Text and why is it crucial?

Speech-to-Text (STT) is the first step in any conversational analysis: it transforms your call audio into usable text. The quality of this transcription directly impacts the reliability of all subsequent analyses - whether for Quality Monitoring, Sales Compliance or Voice of Customer insights.

At Raisetalk, we now offer 8 different STT models to cover all use cases. But how do you choose the right one?

What criteria should guide your STT model choice?

Six main criteria should guide your choice:

What models are available on Raisetalk?

Here's the complete comparison of the 8 available STT models, ranked by total score:

Legend: all scores are out of 5, higher is better. The feature bonus rewards multi-region availability, long duration support, translation and pseudonymization.

Which model for prospecting and qualification?

For prospecting calls, Sales Compliance is often a key issue: verifying that sales reps follow the script, present legal disclaimers, and don't make non-contractual promises. Two approaches depending on your constraints:

Light is the versatile choice:

• Highest total score: best overall value
• All features: translation and pseudonymization included
• Maximum speed: near-instant results
• All durations supported: no practical limit
• Controlled cost: economical for high volumes

Parakeet is the specialized choice if diarization is critical:

• Perfect diarization: clear distinction between speakers - essential for attributing statements to the rep vs the prospect
• No time drift: precise navigation in the recording to replay a passage
• Maximum speed: near-instant results

Parakeet's constraint: no pseudonymization or translation, and only available in the Europe region.

Which model for sales teams?

Sales conversations are longer and more complex than prospecting. They serve Quality Monitoring (evaluating sales techniques, commercial process compliance), Voice of Customer (objections, expressed needs, buying signals) and of course Sales Compliance, especially in banking and insurance. They require a balance between quality, diarization and advanced features.

Best is the premium choice:

• Best text quality: maximum precision on business terms and customer objections
• No time drift: perfect synchronization for targeted replay
• All durations supported: no practical limit
• All features: translation and pseudonymization included

Gemini 2.5 Flash offers a good compromise:

• Better diarization than Best - useful for clearly distinguishing sales rep and customer
• More cost-effective than Best
• Durations up to 25 minutes: covers most commercial calls

Which model for customer support and long conversations?

Technical support calls can last 30, 45 minutes or more. They're a goldmine for Voice of Customer (pain points, feature requests, satisfaction) and Quality Monitoring (procedure compliance, resolution quality, empathy). Every word counts.

Best is often the best choice:

• Maximum transcription quality: precision on technical vocabulary and expressed emotions
• No time drift: perfect synchronization to replay key moments
• All durations supported: no limit, even for very long calls
• Speed: near-instant results

Gemini 2.5 Pro is justified if diarization is critical:

• Perfect diarization vs Best: crucial when multiple speakers alternate (transfers, escalations)
• Maximum transcription quality: equivalent to Best
• Durations up to 45 minutes: covers most support calls

Gemini 2.5 Pro's trade-off: it's the most expensive and slowest model. Reserve it for conversations where multi-speaker diarization is non-negotiable.

Why do `Light` and `Best` dominate the ranking?

Light and Best lead the overall ranking thanks to their versatility:

In summary:

• Light: best value for high volumes - ideal for analyzing 100% of conversations for Voice of Customer
• Best: best text quality for demanding cases - perfect for Quality Monitoring and Sales Compliance

Both models have the advantage of having no announced end-of-life date.

When to choose `Parakeet` or `Whisper`?

These two models share similar characteristics: excellent diarization, no time drift, maximum speed, and support for all durations. But they offer neither translation nor pseudonymization, hence their lower total score.

Parakeet is recommended if:

• Perfect diarization is your absolute priority
• You don't need pseudonymization
• You're in the Europe region

Whisper (faster-Whisper-large-v3-turbo) has lower transcription quality compared to Parakeet. We offer it for:

• Comparative testing
• Users who already know it and want to compare

What end-of-life dates should you anticipate?

Some models have a scheduled end-of-life. Here's the timeline:

If you're using Gemini 2 Flash, plan your migration now to Gemini 2.5 Flash or another model.

These dates are subject to change. We'll keep you informed of any updates.

Need help choosing?

Our team can help you identify the optimal configuration based on your volumes, budget and quality requirements.

You can also test for yourself on our trial space: https://app.raisetalk.com/try