Simulate realistic callers at scale with custom personas, scenarios, interruptions, noise, accents, and network conditions. NovaSynth runs those calls against your voice agent, scores audio and transcripts across 30+ dimensions, and surfaces the failures and fixes that matter to your team.
Voice agents have guardrails, scripted tests, and observability. The caller is still a variable
Real callers don’t work that way.
- The Interrupter: Cuts you off mid-sentence, talks over the agent, then demands an immediate answer. - The Second-Guesser: Agrees, then changes their mind twice and asks for a completely different option. - The Hard-to-Understand Caller: Speaks softly, switches pace, uses an unfamiliar accent, and repeats themselves. - The Distracted Ones: Calling from a crowded, noisy place with people talking, traffic, and constant interruptions around them. - The Frustrated Caller: Starts impatient, gets increasingly annoyed with every extra question, and is close to hanging up. - The Unstable Connection: Audio drops, words get clipped, pauses appear unexpectedly, and the caller repeats themselves.
And you can’t keep relying on a human tester to recreate every one of those situations.
Why NovaSynth Exists
A year ago, Shashank and I were working on voice agent evaluation when someone said:
“The happy paths are working fine. I pray the agent works well when a weird customer picks the call."
That question stayed with us. It became the starting point for NovaSynth, a pre-production testing platform built around simulated callers.
KEY FEATURES
→ Build the caller, not just the test: Create personas and scenarios around accent, mood, behavior, interruptions, noise, network conditions, and caller intent.
→ Mix and match personas and scenarios: Create different callers for different situations, then test any persona against any scenario as your agent evolves.
→ Run real voice interactions: Simulate calls through real audio and telephony paths, capturing voice-specific issues such as latency, interruptions, and audio quality.
→ Evaluate beyond the transcript: Score calls across 30+ audio and 100+ transcript scorers, plus the business KPIs your team cares about.
→ Validate fixes before shipping: Use NovaPilot to recommend fixes, then backtest and re-run them against your own calls and traces.
We’re here today, Shashank and I will be around all day to answer any of your questions or doubts.
Congrats on the launch! Curious to know how accent and language works with different personas? Can different personas be configured based on different ICPs / markets?
Congratulations on the launch 🎉
This resonates with me I spent time fine-tuning XTTS for voice cloning and one of the hardest parts was evaluating output quality beyond cosine similarity scores. Transcripts alone miss so much: the naturalness, the pacing, how the voice holds up under real conditions.
The idea of simulating callers with interruptions, accents, and noise to stress-test voice agents is exactly the kind of evaluation layer that's been missing. Audio-based scoring is the right signal.
Excited to see where Noveum takes this rooting for you! 🚀
@NovaSynth by Noveum Congratulations on the launch! Testing voice agents against interruptions, noisy environments, unstable connections, and changing caller intent before production is incredibly useful. Excited to see NovaSynth tackle this.
Congrats on this launch builders , what's one distinguish thing about noveum that you are proud of building ?!
This is genuinely cool. I like that you’re testing voice agents through actual conversations instead of just checking transcripts.
How the industry is moving this is so critical before we burn more money on low relevance context and better in call exceptions and objection handling.
For teams already running their own voice agent tests what does it add that is hardest to reproduce internally?
Can it test things like delays or dropped audio in the middle of a conversation?
Pretty great usecase actually. we've also seen these requirements and need for a specific tool among our clientele.
Voice agents are always being upgraded regularly – does NovaSynth have any kind of automation in place for the purpose of doing regression testing as part of the CI/CD process? Btw, Congratulations @itsshashank@additi & team @NovaSynth by Noveum 🚀
Anything that makes AI evals easier is a big blank space across modalities. This is a fantastic space to be building in - kudos to you folks! Are you thinking of sticking to voice agents, or would you be doing persona testing on chat based apps at some point too?
I am building a voice agent for a niche case, and NovaSynth is exactly what I need to pressure-test my solution before it hits production and starts serving my users.
This looks great. Very helpful for businesses looking to setup voice agents
A great way to ensure in prod our voice agents give comparable quality as we got in our pilots !!!
About NovaSynth by Noveum on Product Hunt
“Test your voice agent on the callers you can’t stage.”
NovaSynth by Noveum launched on Product Hunt on September 17th, 2026 and earned 201 upvotes and 49 comments, placing #5 on the daily leaderboard. Simulate realistic callers at scale with custom personas, scenarios, interruptions, noise, accents, and network conditions. NovaSynth runs those calls against your voice agent, scores audio and transcripts across 30+ dimensions, and surfaces the failures and fixes that matter to your team.
NovaSynth by Noveum was featured in Developer Tools (519.6k followers), Artificial Intelligence (478.9k followers) and Audio (2.2k followers) on Product Hunt. Together, these topics include over 210.4k products, making this a competitive space to launch in.
Who hunted NovaSynth by Noveum?
NovaSynth by Noveum was hunted by Rohan Chaubey. A “hunter” on Product Hunt is the community member who submits a product to the platform — uploading the images, the link, and tagging the makers behind it. Hunters typically write the first comment explaining why a product is worth attention, and their followers are notified the moment they post. Around 79% of featured launches on Product Hunt are self-hunted by their makers, but a well-known hunter still acts as a signal of quality to the rest of the community. See the full all-time top hunters leaderboard to discover who is shaping the Product Hunt ecosystem.
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Rohan Chaubey
Hi Product Hunt 👋
I’m Additi, co-founder of Noveum AI.
Voice agents have guardrails, scripted tests, and observability. The caller is still a variable
Real callers don’t work that way.
- The Interrupter: Cuts you off mid-sentence, talks over the agent, then demands an immediate answer.
- The Second-Guesser: Agrees, then changes their mind twice and asks for a completely different option.
- The Hard-to-Understand Caller: Speaks softly, switches pace, uses an unfamiliar accent, and repeats themselves.
- The Distracted Ones: Calling from a crowded, noisy place with people talking, traffic, and constant interruptions around them.
- The Frustrated Caller: Starts impatient, gets increasingly annoyed with every extra question, and is close to hanging up.
- The Unstable Connection: Audio drops, words get clipped, pauses appear unexpectedly, and the caller repeats themselves.
And you can’t keep relying on a human tester to recreate every one of those situations.
Why NovaSynth Exists
A year ago, Shashank and I were working on voice agent evaluation when someone said:
“The happy paths are working fine. I pray the agent works well when a weird customer picks the call."
That question stayed with us. It became the starting point for NovaSynth, a pre-production testing platform built around simulated callers.
KEY FEATURES
→ Build the caller, not just the test: Create personas and scenarios around accent, mood, behavior, interruptions, noise, network conditions, and caller intent.
→ Mix and match personas and scenarios: Create different callers for different situations, then test any persona against any scenario as your agent evolves.
→ Run real voice interactions: Simulate calls through real audio and telephony paths, capturing voice-specific issues such as latency, interruptions, and audio quality.
→ Evaluate beyond the transcript: Score calls across 30+ audio and 100+ transcript scorers, plus the business KPIs your team cares about.
→ Validate fixes before shipping: Use NovaPilot to recommend fixes, then backtest and re-run them against your own calls and traces.
We’re here today, Shashank and I will be around all day to answer any of your questions or doubts.
Start a Free Trial: https://bit.ly/4zOcEXT
Book a Demo: https://bit.ly/4gtBXae
And I’m curious:
What’s one caller you wish you could test your voice agent against, but have never been able to recreate?