Show HN: Subvocal – Talk to your computer without making noise
280 points - today at 5:16 PM
Hi HN, we're Aarush and Arnav from The Subvocal Company (YC F26). We’re building smart glasses that let you talk to your computer without talking out loud. You can mouth words silently and discreetly and the glasses decode them to text at the speed of speech.
Here's a video of Dave from YC trying it out: https://www.youtube.com/watch?v=9QdX1eObVYI
(Edit: you don't actually have to move your lips or even open your mouth for this to work! Since the RF can see inside your mouth the system can be fine tuned on "internal speech". This isn't the automatic tongue movements that occur when "thinking" words to yourself, but more like mouthing with your lips closed. It's a bit weird to do, but with practice, we have been able to get it down pretty well.)
Arnav and I were studying CS at Georgia Tech at the beginning of the year, with no experience in silent speech or sensing. We were both AI-native builders and power users of Wispr Flow. What bugged us was not being able to use these tools in the library (or an office) or in public. At Stanford’s TreeHacks in February, we decided to build the most technically ridiculous thing we could think of. We’d read about AlterEgo, a silent speech system out of MIT’s Media Lab, and wanted to recreate it in 36 hours. We built a crude prototype, sticking EMG electrodes onto my face:
https://drive.google.com/file/d/1mwhv5HZMz3UTevdrgwS5O7g2jWV...
We got it to kind of work at a letter level in a very janky way. It wasn’t good enough to win the hackathon, but convinced us to go all in. The first time I typed a sentence without anyone noticing, I felt the magic of the technology.
We quickly realized EMG (reading muscle electrical signals) wouldn’t work:
- Signal changes due to sweat
- Electrical interference
- Placement variability
- Most importantly, no one wants to stick electrodes onto their face!!
So we switched to RF and built the glasses you see now. They emit radio waves, similar to Bluetooth, that pass through your face. As they cross the tongue, lips and soft palate, they’re modulated by silent mouthing. We train foundation models on this data to decode these perturbations to text.
Despite prior academic research, getting this to work was a huge engineering challenge. First we built an extremely low noise RF sensing stack. Then we had to place antennas so their fields overlapped maximally with the articulators. Our first attempt on glasses failed completely, so we reverted to old habits and taped antennas on our face:
https://drive.google.com/file/d/1ks0dS0eZiTV9EqSFsyB_w5BBjpc...
Since taping antennas consistently in the same spot and angle was hard, we created this weird but effective head rig to hold them in place:
https://drive.google.com/file/d/1rhzNFpdDzr7oHk0isFY70dkoV4C...
This worked, but obviously wasn’t a product yet. So we worked deep in simulations to design glasses that could hold the antennas.
That evolved into our design now, with antennas embedded within the frames. Once we established there was a signal, the next hurdle was cross-user generalization. Everyone’s facial anatomy, and hence RF signal patterns, are vastly different. We tried algorithmic workarounds but realized the only lever was to massively scale pretraining data.
So that’s what we did. We set up booths in our office and paid people to read prompts wearing our glasses, to pretrain our models on. This produced a beautiful scaling curve, with errors falling quickly as we scaled our dataset and cross-user performance becoming genuinely compelling (as you see in the video above; Dave only had a short 20-sentence calibration).
We always heard about building things from first principles but never understood it before this. We tried tackling it top down but completely failed. Only when we broke each component (the antenna, electronics, ML) down to its fundamentals to understand and optimize it did we get it to work really well.
Over the next few months we’re continuing R&D to turn our prototype glasses into the slick product on our website and ship in Q1 2027. We’re also scaling up our dataset to improve performance on edge cases.
For anyone who loves voice dictation but hates using it around people, we’ve opened preorders for our first batch of 500 units, with a $200 discount off the final price. Allocation is running out quickly, so get yours at https://subvocal.co/preorder!
Comments
Second, how tough is this signal processing? Will it be done on-glasses, or through an app? Third, what's the equivalent of a wake word for these? I'm reminded of the Apple Vision Pro radar to see if your fingers are clicking. I could imagine a lot of modalities where I want to just start talking and have things happen, and a lot where I don't want the glasses to pick it up. Fourth, I think a cool voice change demo would be rad -- not sure what latency is like, but if you could get it end to end under like 250ms you could probably have someone exaggerate the mouth movements and pipe out audio of them talking like someone else. Which would be another really cool demo.
Super cool. You're going to be working 80 hour weeks for the next year, I'm excited to see what you put out!
Maybe I could have figured that out from the video but for folks who can’t watch the video it’s quite hard to discover what you’re building.
1. Insanely cool
2. Gives me serious "whispering earring" vibes. Imagine having a full on conversation with an AI via subvocalization and listening with ear bud to guide you throughout the day. https://gwern.net/doc/fiction/science-fiction/2012-10-03-yva...
I don't think it is an intuitive action at all and I became self-conscious about not making a sound rather than talking like I normally would.
I suppose it would require some "getting used to."
Regardless, I think it is a cool idea and a real problem. Sometimes I don't want to type nor talk out loud so I find myself whispering at my phone like I'm telling it a dirty secret.
--
As I'm writing this, I think this kind of product might not hit the market for consumers, but I'm seeing this used by Flock like companies to spy on people's speech, so kudos on making machine lip reading a thing!
So this could take "noise canceling" to a whole new level if you could somehow "speak" across a loud bar or across the world, for that matter. Being integrated into something like Signal or similar end to end encrypted platform would be interesting as well.
https://github.com/joeblau/subvox
There was this really interesting one where it reads your lips:
https://github.com/amywork777/lipflow
I’m using these to build my own so I can work in co-working spaces, planes, and libraries. Though moving my mouth with no words might draw some eyes.
I wonder if we could eventually end up with a "throat muscle" version where people learn to talk a new way without having to move the visible mouth muscles too.
Just preordered.
What languages do you support? (English is fine, but any others?)
Throat mics don't work at all - see reviews online.
This is a different approach, so I am cautiously optimistic.
Edit: mostly concerned about RF near my eyes for 8 hours a day.
Really like seeing the early prototypes here, and would love to see more on how the RF tech works on the website.
Are you able to patent it?
Regarding the website, you should lead with product, its details, rather than founders shown in 360 degrees from various vantage points. It is distracting and frankly irritating.
Calling it early - this is a scam. There's no way they're going to deliver that product, in that form factor, by Q1 2027.
And after some time I could not figure out what this is?
Put this part: " building smart glasses that let you talk to your computer without talking out loud. You can mouth words silently and discreetly and the glasses decode them to text at the speed of speech."
right at the top and maybe show someone actually doing that instead of hiding behind cryptic marketing.
Also, the product looks great.
Get your words out of the way 'say what it is'.
Very amazing tech though
Can we use RF for other medical applications? As an anesthesiologist, we do nerve blocks before surgeries or for pain. One rough indicator that it's working is muscle paralysis. Also similar for botox.
Very interested.
https://www.cnet.com/tech/services-and-software/apple-qai-ac...
Hope you guys are well-positioned patent-wise.
From your comments it seems to reach this point you tried at least open source lip reading software, IMUs, variant antenna mounting strategies, various frequencies, and then gathered training data. You articulated strongly why the product is desirable and why the failed modes were dead-ends. I hope you can deliver on your pre-orders and are able to scale and/or sell the IP for a strong exit.
Anyone who preorders - you are getting scammed.
Pangram: https://www.pangram.com/history/images/614ffe91-8ba9-4d3c-b1...
That said, I think the idea of having a private walkie-talkie that connects on its own frequency for large crowded spaces to be very cool
All of them are visionary and we would think that ppl gonna like them…
Well… ordinary people want boring tech.
This will be similar with whispering to glasses… Visionaries will like it… and return to missionary (boring) s*x (I hope that I don’t get a ban.)
Myself, I would buy these glasses immediately. But I would hate them as well as I would think I am insane (who wants to talk to yourself?).
Edit: Dang replied. I wish all the best to the team behind “whisper glasses”. It is amazing. Connect it with ElevenLabs and you rule the world. (Previous: It wasn’t meant a hate speech.)