Optical to Analog Conversion

I guess since Sony owns so much program material, they want to keep it un-copyable.

Why not just tap the speaker drive, voltage divider and transformer maybe? Even that will get interesting as more stuff goes class-D.

John

[snip]

Yep. That's what I'm getting here too... dad is "into electronics".

But it's to my advantage... oldest son is a _very_good_ programmer, so I'll meet his electronics needs... in exchange for him writing me some more PSpice utilities... maybe a netlist comparator ;-)

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

That was the first thought. Have any keen ideas on leveling it? Otherwise somewhat of a nightmare to keep proper levels at remotes.

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

Radio Shack sells an inexpensive ($15) analog to SPDIF/ TOSlink converter (15-1242) Alas, seems like the wrong direction. (Unless he uses it on one of the inputs.)

Have look at DA96: 4 channel, 24 bit, 96 kHz ADAT optical to analog converter - 1/2 rack space.

I have no experience with it but might in the future. My daughter has embarked on a musical carrier and since dad is "into electronics" all of the tech support should be easily accessible. Looks like I have to embark on crash audio course..

--

    Boris Mohar

i was working on this a while back, it's for converting ethernet to optical. it needs a lot of work, but it's a start, one that uses a prism, the other uses separate optical parts. you definitely wouldn't need the inverter. the connector that's on the optical out can probably have some fibre driven into it, you run the fibre to the room you want it to supply, then you add a storebought ir transistor with integral holder, some power, and an rca plug. the ends of the fibre needs to be near perfect flat, you can use a hot razor blade to do that. but don't mind me, i have no idea what i'm blathering on about.

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I read in alt.binaries.schematics.electronic that Jim Thompson wrote (in ) about 'Optical to Analog Conversion', on Sun, 1 May 2005:

Some sort of anti-copying measure? If you can get a schematic from a consumer product manual supplier, you might be able to make a bridge between the channels.

Maybe you can get a hi-fi preamp with optical inputs and analogue outputs.

It's not a trivial task at all; not that I'm saying you couldn't do it, but it's a lot of work.

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Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
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I read in alt.binaries.schematics.electronic that Boris Mohar wrote (in ) about 'Optical to Analog Conversion', on Sun, 1 May 2005:

Not the Brian Ferry? (;-)

--
Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
'What is a Moebius strip?'
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

Jim,

Is the optical output 44.1KHz S/PDIF (TOSLINK)? If it is, I've just designed a board that converts just that into stereo line-level audio. It isn't trivial (and my design certainly isn't audiophile quality - only 12-bits for a start). It was done mostly as a learning exercise).

If it's DTS 5.1 surround (or anything other than plain stereo) then your cheapest option is probably a PC with a soundcard that has an optical input - amps with optical in look expensive.

Let me know if you're interested in my decoder design - here's a snap of it (only just today commissioned the PCB!):

I intend to put it on the web eventually anyway, just a matter finding the time!

Regards,

--
Ian

"Tamahome!!!" - "Miaka!!!"

I read in sci.electronics.design that Jim Thompson wrote (in ) about 'Optical to Analog Conversion', on Sun, 1 May 2005:

Not only at remotes, in UK. TV audio levels vary over almost a 20 dB range (same channel, more that 10 dB within the same programme) since no-one is apparently now employed to watch the level meters.

That Corp. THAT4301 can apparently be used as an AGC (not compression) device that gives an approximation to 'constant loudness' audio output, although the makers don't say so, AFAIK. I'm working on the design now (between commuting round the world on standards business).

--
Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
'What is a Moebius strip?'
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

Hello Jim,

If this is a Toslink output you might want to search Google for "Toslink adapters". I have seen them in a large store, but cannot remember where because I didn't need one. We lucked out since our mini-disk unit had both fiber and regular line outputs so I didn't buy the converter.

Regards, Joerg

I looked-up that part. Seems promising. What sort of application are you working... your audio loop?

I downloaded the data sheet and all the apnotes.

Since the speakers are likely bridge driven, do you have recommendations as to how to take off the signal? Transformer? Ground loop issues?

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

"John Woodgate" a écrit dans le message de news: snipped-for-privacy@jmwa.demon.co.uk...

LOL. Ha ha ha... excellent John.

Isn't the Brian Ferry a kind of "boite à musique" ?

--
Thanks,
Fred.

"Jim Thompson" a écrit dans le message de news: snipped-for-privacy@4ax.com...

the

How much jitter will you get into the output?

--
Thanks,
Fred.

FYI,

--
Ian

"Tamahome!!!" - "Miaka!!!"

A small (less than 1MB) fast free PDF reader is at:

Robert

Hello Jim,

Just a thought: If this is a Toslink output (should say in the manual) then you might be able to buy a converter. I have seen these a long time ago in a big box electronics store but forgot which one. It wasn't very expensive.

If you have to impress your son you could still provide your own enclosure, or pretend it had to be flown in from Japan ;-)

Regards, Joerg