How it works2 min read

Do they actually sound human?

The voice is rarely the problem. What gives most of them away is timing.

Published 25 February 2026 · Updated 15 August 2026

Everybody selling one of these says it sounds human. Most people who have used one say it did not. Both are describing something real, because the voices have got very good while the conversation handling has improved unevenly.

If you know what to listen for, you can judge one in about ninety seconds.

The three tells

The pause before answering. A person begins responding almost immediately, sometimes before you finish. A system that leaves a beat of silence before every reply is recognisable within two exchanges, and it is the most common giveaway.

Talking over the caller, or refusing to be interrupted. Real conversation involves overlap. A system that ploughs through its sentence while you are trying to speak is instantly a machine, and worse, it is irritating.

Perfect grammar and no filler. People say so, right, and let me see. A reply delivered in flawless prose with no hesitation sounds like something being read.

Why timing matters more than voice quality

Human speech has a turn taking rhythm measured in a couple of hundred milliseconds. We are extremely sensitive to it, without knowing that we are, and a delay of a second reads as wrong even when the voice itself is flawless.

This is why an ordinary voice with excellent timing sounds more human than a beautiful voice with a lag. Judge the gaps, not the tone.

Easier to hear than to read about

Callwise answers your phone the way this article describes. Ring it, ask it something awkward, and see whether it holds up.

Talk to our AI assistant

How to test one properly

Ring the provider's demo line and be difficult on purpose. Interrupt it mid sentence. Change your mind. Give a piece of information and then correct it. Ask something completely outside its remit.

Then ask it a question you know it cannot answer and listen to what it does. Saying it does not know and offering to take a message is the right answer. Producing something confident and wrong is disqualifying, because your customers will believe it.

Interrupt it halfway through a sentence
Give it a wrong detail then correct yourself
Ask something outside its subject entirely
Speak over background noise, from a car if you can
Ask for a human and see how quickly it agrees

Should it pretend to be a person?

No. Beyond the ethics, it fails in practice. Callers who suspect they are being deceived stop cooperating and the call goes badly.

Saying it plainly costs almost nothing. In our own recordings, callers who are told at the start simply continue with what they rang about.

The accent question

For UK businesses, an assistant that handles UK accents, postcodes and phone number conventions matters more than which accent it speaks in. A voice that cannot take a Glaswegian postcode is a problem regardless of how pleasant it sounds.

Questions people ask

Will my customers be able to tell?

Some will, particularly early in a call. What matters more is whether they get what they rang for, which is why the ones that book successfully get very few complaints.

Does it handle background noise?

Good ones cope with a car, a building site or a busy street. Test it from the environment your customers actually ring from rather than from a quiet office.

Hear it answer a call

Ring the assistant and ask it the awkward question your customers always ask. If you like what you hear, it will book you in there and then.

Talk to our AI assistant

No form, no sales call. Thirty seconds on the phone with the thing itself.