Echo built for Pipecat · any TTS provider For developers Get early access

Echo powers 60% cost savings on TTS

  • Listens to your calls
  • Chunks repetitive phrases
  • Streams them from the cache instead of re-synthesizing them

Reuse the voice you've already paid your TTS provider for.

Early access is rolling out to teams building Voice AI with Pipecat.

01 — where the money goes

Voice makes the first impression. It also makes the bill go brrr…

Across a typical voice AI stack, text-to-speech is the single largest line item — bigger than your LLM and transcriber put together.

Cost per call — voice AI stack
TTS cost, halved
15%Speech to text
25%LLM
30%Text to speech
30%Cached by Echo

Text to speech is 60% of the cost of a call. Echo caches away half of it. Replaying a cached phrase costs 1% of synthesizing it again.

Echo, on.
Pipecat
Pipecat pipeline
Echo goes straight to the biggest slice — delivering a large amount of savings. up to 60% off your TTS bill

02 — how echo does it

Your agent says the same things all day long.

Greetings, confirmations, hold lines, tool calls, closings. Echo learns them once and you never pay for them again.

Step 01

Listens

Echo sits inside your Pipecat pipeline and observes live calls — no rewrite, no new voice vendor.

Step 02

Chunks & caches

It splits speech into reusable phrase-level audio chunks, keyed to the exact text your LLM produces.

Step 03

Replays

Next time that phrase comes up, Echo rapidly streams the cached audio. No TTS call is made resulting in direct savings.

03 — one real call, annotated

Watch a call go by with Echo switched on.

Six agent responses. Only one of them ever reaches your TTS provider.

Call #4,181 — account activation

inbound · 1m 12s
Agent · LLM
Hello, thank you for calling ABC Shop.
Echo match$0 TTS
Customer
Hi, I need help with account activation.
Agent · LLM
Sure, I can help you with that.
Echo match$0 TTS
Agent · LLM
Please confirm your account number.
Echo match$0 TTS
Customer
It's 12345.
Agent · LLM
12345, got that. I have your details here — am I speaking with Jane Doe?
TTS streamdynamic variables
Customer
Yes, that's correct.
Agent · LLM
To activate your account, I've sent a one-time code to your registered phone. Please confirm the code with me when you see it.
Echo match$0 TTS
Customer
It's 987654.
Agent · LLM
Perfect, you're all set. Your account should be active in 30 minutes. Is there anything else I can help you with?
Echo match$0 TTS
Customer
That's all, thanks.

— call ends —

5 of 6 served from cache
83% saved on TTS for this call
Live on this call
5cache hits
1TTS calls
“Hello, thank you for calling…”
“Sure, I can help you with that.”
“Please confirm your account…”
“To activate your account…”
“Perfect, you're all set…”

Echo's cache, filling up as the call runs.

Your TTS provider
idle

Idle most of the call. Still your voice, still your quality.

04 — where it fits

Drops into Pipecat. Keeps whatever voice you chose.

Echo is a TTS Gateway for Voice AI agents and is TTS model agnostic. It caches the audio your TTS engine already produced, so nothing about your voice changes. Echo is now available on Pipecat.

ElevenLabsCartesiaDeepgram OpenAIAzureRimeGeminiSarvam …or whatever you switch to next

Get early access

One email when we open your slot. Nothing else.