Error Show more

@anarchiv I was going to try the very same thing. :D

@lynnesbian to the rescue?

@esureL @anarchiv sometimes posts don't federate properly, this is a known issue and i don't really know how to fix it

@yogthos @M0YNG

Good news - you're going to learn something today as well!

Yes, Klatt's voice is the template for Perfect Paul, the DECtalk voice that Hawking came to prefer. ('Beautiful Betty' was Klatt's wife, 'Kit The Kid' his daughter.) He did die in 1988.

@yogthos @M0YNG

Klatt had been working on voice synthesis since the mid 1960s, producing a source filter algorithm which was licensed to Digital Equipment Corporation. The first DECTalk units came out for telephones in 1984.

@yogthos @M0YNG

In 1986, when Hawking first needed a voice synthesizer, they were commercially available. He first used a software package by Words Plus, Equalizer on a Apple II as the control system.
Sources are vague about the first synthesizer, but by 1988 he was definitely using a Speech Plus CallText 5010. Speech Plus used DECTalk 'Perfect Paul' as single voice for this unit, but had apparently been refining it for 10 years.

@yogthos @M0YNG

The control system was made portable and updated repeatedly, but he kept using the CallText 5010 for nearly years, refusing to switch to a different voice, even other refinements of Perfect Paul. In 2017, as the hardware , he changed to an emulated version running on a Raspberry Pi.

@bezt @yogthos I suspected that it might not be entirely true. That will teach me to boost first and check later!

Thanks for taking the time to explain the still very interesting story.

I find the change of hardware fascinating, from an apple 2 to a raspberry pi!

@M0YNG @yogthos No worries!

On hardware: the system was divided into the control interface and the synth box. The Apple II ran the first control system, and wasn't portable. Later refinements ran on all sorts of things- Commodore PET, BBC Micro... Intel eventually made him a custom system running ACAT.

@M0YNG @yogthos The RPi was emulating the synth box in software- the story of developing that system (included in the links above) is a real saga. There's more on the original synth hardware at

OCR Output Show more

Sign in to participate in the conversation

Invite-only Mastodon server run by the main developers of the project 🐘 It is not focused on any particular niche interest - everyone is welcome as long as you follow our code of conduct!