[chetatkinsdiet]

As someone who's worked with a lot of these engines, Nuance and IBM are the only really high quality players in the space. CMUSphinx and Julius are fine for low volume operations where you don't need really accurate response rates, but if you want high accuracy neither comes close from my experience.

[hardwaresofton]

Right, but they do offer you a fantastic starting point. If Nuance is 100%, I'd say CMUSphinx is at least 40%.

Also, they give you the tools and knowledge to build better models (and explain the theory), which is where most of the competitive advantage is IMHO.

[IshKebab]

As someone who has actually done objective tests, Google are by far the best, Nuance are a clear second. IBM Watson is awful though. Actually the worst I've tested.

[Pafnouti]

Do you have a report of your tests? I'm interested in using speech recognition, but there are many start-ups and big players that it would be quite time consuming to get a quality/price analysis.

[dr_zoidberg]

For the "dialect" of spanish that we speak in Argentina, Watson misses every single word. So, to me, CMUSphinx is valuable in that it allows me to tweak it, while IBM miserably fails at every word. Must've been trained with Spain or Mexican "neutral" spanish.

Googles engine also works fine (have been trying it with the phones), but the pricing may or may not be a deal breaker.