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Model infoModelsSnapshot: 15 Oct 2026

Sophea AI · KIEFER SA / Sophea speech research

Sophea large Whisper adaptation · L4

Paper-identified proprietary Greek/English Whisper adaptation, shipped with additional decode-time silence and boilerplate controls.

restrictedClosed weightsSpeech recognition
Official documentation (opens in a new tab)Reviewed 13 Oct 2026
5 of 17 specification fields collected
Context windowNot collectedAwaiting source review
Maximum outputNot collectedAwaiting source review
Input billingNot collectedKIEFER SA · paper-documented system
Output billingNot collectedNo inferred price

Specifications

Provider-documented facts. “Not collected” means we have not verified that field yet, not that the feature is unsupported.

Context / input limit
Not collected
Maximum output
Not collected
Reasoning
Not collected
Tool calling
Not collected
Structured output
Not collected
Streaming
Not collected
Batch processing
Not collected
Fine-tuning
Not collected
Knowledge cutoff
Not collected
Release date
Not collected
Parameters
Not collected
Architecture
Internally trained Whisper-family adaptation; L4 weights with later L7 decode-time configurationSource for Architecture (opens in a new tab)

L7 changes a suppression phrase list without new weights, so it is not counted as a new checkpoint.

Context caching
Not collected

No model-specific prompt-cache contract verified. Server-side audio segmentation, speech buffers and reused decoders do not establish discounted token caching.

Research controls
Voice-activity gating, calibrated no-speech/log-probability thresholds and audited boilerplate phrase filteringSource for Research controls (opens in a new tab)

No exact serving API fields or threshold values are supplied. These are research implementation details, not advertised public controls.

Access & pricing

Prices belong to an endpoint and billing tier. A provider listing does not guarantee access for every account or region.

KIEFER SA · paper-documented system

Provider source (opens in a new tab)
API model ID
Not collected

No public immutable checkpoint selector or standalone API contract verified for this dated/internal system.

Access
Internal shipped model line documented in the September paper. Exact private artifact, current selector, access and price require provider confirmation.
Regions
Original experimental deployment location not specified

Endpoint pricing has not been collected. Check the provider for applicable rates.

Data & enterprise terms

The paper releases no model weights, data or internal tooling. No standalone processing agreement or data-retention contract is established for this paper-only/datetime-specific record; current preview policies are not backfilled.

Read the service policy (opens in a new tab)

Caching

Caching can reuse earlier input processing. Availability, lifetime and billing depend on the endpoint. A cache hit still generates a new response.

01 / INITIAL INPUTProcess & retain

The system processes eligible input and retains reusable state.

02 / LATER REQUESTCheck available state

Reuse depends on matching input, session state and the cache policy.

03 / CACHE HITReuse & generate

Reusing state can reduce repeated work. Any charges follow the billing rules below.

KIEFER SA · paper-documented system

Not verified

No model-specific prompt-cache contract verified. Server-side audio segmentation, speech buffers and reused decoders do not establish discounted token caching.

How it works
Not collected

No model-specific prompt-cache contract verified. Server-side audio segmentation, speech buffers and reused decoders do not establish discounted token caching.

Minimum reusable input
Not collected

No model-specific prompt-cache contract verified. Server-side audio segmentation, speech buffers and reused decoders do not establish discounted token caching.

Lifetime & refresh
Not collected

No model-specific prompt-cache contract verified. Server-side audio segmentation, speech buffers and reused decoders do not establish discounted token caching.

How to enable it
Not collected

No model-specific prompt-cache contract verified. Server-side audio segmentation, speech buffers and reused decoders do not establish discounted token caching.

Usage fields
Not collected

No model-specific prompt-cache contract verified. Server-side audio segmentation, speech buffers and reused decoders do not establish discounted token caching.

Billing rules
Not collected

No model-specific prompt-cache contract verified. Server-side audio segmentation, speech buffers and reused decoders do not establish discounted token caching.

Limits & data boundaries
Not collected

No model-specific prompt-cache contract verified. Server-side audio segmentation, speech buffers and reused decoders do not establish discounted token caching.

No verified cache rate for this endpoint. An empty rate is not a zero charge.

What the measurements say

Large production model · FLEURS Greek

KIEFER SA / Sophea authors · provider-reported
9.13% WER

Table 2 large production model column. Not Table 3’s separate Whisper ensemble member or an all-Greek accuracy score.

Evaluation source (opens in a new tab)

Latency and throughput depend on the host, request size, reasoning settings and load. There is no measured speed or global usage figure in this record.

The record behind the model

Why it is included

The provider-authored production paper identifies internal adapted speech models and combined systems and explicitly releases none of their weights, data or tooling. This record covers the specified proprietary adaptation/system; the original Qwen, Whisper and Canary base weights and stock-weight Turbo are not reclassified as closed.

Classification evidence (opens in a new tab)

Sources reviewed