HOWTO: Read Dolby SR-D audio from sound negatives

[Simon Wynn]

Hi All,

What an amazing blast from the past to see all of this old tech.

I designed the Dolby CA10 hardware, wrote the front-end PC software in the screenshots, wrote the CP500 system software and likely hand-built that CA10 frame. I do have a CA10 user manual and likely a bunch of other stuff available. Please, if you have any questions, ask away, albeit this was 30+ years ago.

Simon

[David Ferguson]

Hi All,
I designed the Dolby CA10 hardware, wrote the front-end PC software in the screenshots, wrote the CP500 system software and likely hand-built that CA10 frame. I do have a CA10 user manual and likely a bunch of other stuff available. Please, if you have any questions, ask away, albeit this was 30+ years ago.

Wow, you did a lot of the software side of Dolby cinema products! You'll be pleased to know that a lot of this is still running well - I have a DA10 (the original!), DA20 and CP500 that all work brilliantly.

I do have one question... a friend of mine (Dion Hanson - maybe you know/know of him?) showed me this photograph of an early Dolby Digital encoding setup. In it, you can see a PC running some software, the MO drive reader, a mag-follower, and two 3U Dolby units. He called one of them the "EA10" for "Encoder Adapter", and said that this was the setup used for encoding 6 channel analog audio to the Printmaster format on MO disc. However, in other references online, I've heard people refer to the this hardware as the DS10, and then the later version as the DMU. So I'm wondering whether the EA10 was ever a name for this, or was it something else?

dolby-digital-encoder.jpg

[Simon Wynn]

Hi David - I don't remember an EA10, but it's been a long while. The DS10 was used when mixing SRD soundtracks to create the MO disk. It was called a 'DS10' as a natural add-on to the DS4 used for analog surround mixes. The software running on the PC looks like the DS10 software. It uses the same 'windowing' front-end UX as the CA10.

I'm happy to see you are using this old gear, and it still works. I wrote the CP500 software and designed that UX. I left before it shipped, so I missed out on a Technical Oscar

Simon

[David Ferguson]

Hi David - I don't remember an EA10, but it's been a long while. The DS10 was used when mixing SRD soundtracks to create the MO disk. It was called a 'DS10' as a natural add-on to the DS4 used for analog surround mixes. The software running on the PC looks like the DS10 software. It uses the same 'windowing' front-end UX as the CA10.

I'm happy to see you are using this old gear, and it still works. I wrote the CP500 software and designed that UX. I left before it shipped, so I missed out on a Technical Oscar

Simon

Thanks for helping clarify that - I'll try and double check, but it's likely that he meant DS10. I actually have a DS4-E, which I need to connect up to my setup at some point. Never found a DS10 though...

The CP500 UI/UX is brilliant (and whoever had the idea to have the hidden functionality to show the setup password is a forward thinking genius, and should be commended for allowing so much equipment to have an extended life in second run, and home use!). I think the CP650 was a step backwards with a smaller screen, and less obvious button interactions - and the only flaw in the CP500 is the screens fail with age.

[Simon Wynn]

Thanks for helping clarify that - I'll try and double check, but it's likely that he meant DS10. I actually have a DS4-E, which I need to connect up to my setup at some point. Never found a DS10 though...

The CP500 UI/UX is brilliant (and whoever had the idea to have the hidden functionality to show the setup password is a forward thinking genius, and should be commended for allowing so much equipment to have an extended life in second run, and home use!). I think the CP650 was a step backwards with a smaller screen, and less obvious button interactions - and the only flaw in the CP500 is the screens fail with age.

Ha - the secret key combo to reveal the password was my idea. Remember that the CP500 runs a 16Mhz 16-bit processor, so getting that display to work required assembly language code where I was counting instruction cycles.

[Josh Jones]

Those displays were used in all sorts of products. The Orban digital FM processors from the era also used them, and in the hot, often uncontrolled environment of a transmitter site, usually only lasted a few years. I think the reason they were so popular is they were similar form factor to the plasma displays that preceeded them.

Josh

[Christos Gartaganis]

For some reason, the CP500 had a very short life cycle. It was launched in 1996 and withdrawn from the market in 2001, while the CP650 was available for sale from 2000 until 2013. The CP650 had a dsp based Dolby SR decoder, which was working very well.