IVRReady

Technical guide

Contact-center IVR audio requirements: six target packs compared

Compare source-backed file-package requirements with Twilio bidirectional Media Streams raw μ-law delivery, coverage, and conversion behavior.

By IVRReady · Published August 28, 2026 · Last updated August 28, 2026

Direct comparison

Amazon Connect, Webex Contact Center, and NICE CXone use strict canonical μ-law WAV upload profiles. Genesys documents a WAV format matrix and server conversion. Talkdesk greetings accept MP3 or WAV and transcode uploads, while IVRReady currently validates only the WAV path. Twilio Media Streams instead requires raw headerless WebSocket media. IVRReady preserves those differences rather than flattening all six targets into one rule.

“No generic limit documented” does not mean unlimited. It means the cited generic prompt requirements page does not state that limit; another product feature or upload path may impose its own constraint. Twilio’s outbound payload documentation says any size, while practical browser memory and IVRReady safety limits still apply.

Comparison of documented contact center audio requirements
RequirementAmazon ConnectWebex Contact CenterNICE CXoneGenesys Cloud ArchitectTalkdesk GreetingsTwilio Media Streams
TargetAmazon ConnectWebex Contact CenterNICE CXoneGenesys Cloud ArchitectTalkdesk GreetingsTwilio Media Streams
ScopeAmazon Connect Play prompt audioGeneric Webex Contact Center audio promptsNICE CXone Studio prerecorded promptsGenesys Cloud Architect prompt WAV uploadsTalkdesk prerecorded greetings — WAV workflowAudio sent from your application to Twilio during a bidirectional <Connect><Stream> Media Stream
Delivery typeUploadable prompt fileUploadable prompt fileUploadable prompt fileUploadable prompt file + platform conversionUploadable greeting file + platform transcodingRaw WebSocket media payload
Upload containerWAV / RIFFWAV / RIFFWAVWAVMP3, WAVNone — headerless raw media
Accepted formatsG.711 μ-law (0x0007)G.711 μ-law (8-bit u-law) (0x0007 (IVRReady's numeric identity))CCITT μ-Law (G.711) (0x0007)10 documented WAV combinations: PCM 8/16-bit, μ-law, 4-bit ADPCM, and GSM 06.10 at 8,000 or 11,025 HzA structurally valid WAV greetingaudio/x-mulaw at 8,000 Hz, mono, base64 encoded
IVRReady coverageStructurally recognized WAV plus verified correction layoutsStructurally recognized WAV plus verified correction layoutsStructurally recognized WAV plus verified correction layoutsWAV inputWAV input onlyWAV source input
Preferred / canonical formatG.711 μ-law, 8,000 Hz, monoG.711 μ-law (8-bit u-law), 8,000 Hz, monoCCITT μ-Law (G.711), 8,000 Hz, monoGenesys prefers 8-bit μ-law; IVRReady corrections use 0x0007 / 8 kHz / monoTalkdesk runtime: 8-bit mono μ-law at 8,000 Hz; IVRReady does not normalize accepted WAVsValidated 0x0007 / 8 kHz / mono WAV intermediate, then raw .ulaw extraction
Sample rates8,000 Hz8,000 Hz8,000 Hz8,000 or 11,025 HzUpload rate not constrained on cited page; runtime 8,000 Hz8,000 Hz payload
ChannelsMonoMonoMonoNot stated in the cited supported-format matrixUpload channels not stated as a requirement; runtime monoMono payload
File-size limitLess than 50,000,000 bytesNo generic limit documented on the cited requirements pageNo generic limit documented on the cited requirements page25 MB maximum; IVRReady policy: ≤ 25,000,000 bytesGuidance: keep at or below 10 MBTwilio documents any-size payloads; practical browser and IVRReady limits still apply
Duration limitLess than 300 secondsNo generic limit documented on the cited requirements pageNo generic limit documented on the cited requirements pageNo generic duration limit documented on the cited prompt pagesNo generic duration limit documented on the cited prompt pagesNo maximum prompt duration documented for this outbound contract
Platform transcodes?Not part of IVRReady's cited strict upload contractNot part of IVRReady's cited strict upload contractNot part of IVRReady's cited strict upload contractYes — Architect converts uploads to 8-bit μ-lawYes — Talkdesk says any uploaded audio is transcoded to 8-bit mono μ-law / 8 kHzNo — media.payload must already be μ-law / 8 kHz / mono
Last verified2026-08-272026-08-282026-08-282026-08-28, 2026-08-28, 2026-08-282026-08-282026-08-28, 2026-08-28, 2026-08-28
Official sourceAWS — Amazon Connect prompt requirementsWebex Help — Manage audio filesNICE CXone Help — Studio promptsPrompts overviewUpload an audio fileUser prompts in ArchitectWhich audio files are supported for greetings and hold music?Media Streams — WebSocket MessagesMedia Streams OverviewTwiML Voice: <Stream>
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How to interpret source support

“Structurally recognized,” “QA-decodable,” “automatically correctable,” and “target-ready” are distinct outcomes. The target checker reports those facts separately and never treats a filename, extension, or successful FFmpeg exit as proof of compliance.

Technical guides

Sources and evidence

Vendor-specific statements follow IVRReady’s executable target profiles and their recorded official evidence. Technical context uses the primary sources below.