Topic: SPDIF - Coax - Toslink - JB3 (nevermind)....

[KLowe]

Having had several shows ruined by optical cable clicks, drops, noise, etc.  Got to thinking.... could the optical in jack of the JB3 be removed and replaced with a rca terminal for digi-in?

The optical in on the JB3 seems to only have 3 pins to connect.  Seems like it would be easy to desolder and remove existing optical jack and replace with digi-in RCA jack.  Most RCA jacks are two pins (i think).




MIDDLE PICTURE.  The receiver.

Also found this product.which would accept both.  Took apart the JB3 and there seems to be plenty of room to install.

http://www.jalco.co.jp/04product/04pj/pj06.html


Has anyone had experience with de-opti modding a JB3? 

Any ideas?  Anyone already done this?

Thanks,

Kevin

[Church-Audio]

Having had several shows ruined by optical cable clicks, drops, noise, etc.  Got to thinking.... could the optical in jack of the JB3 be removed and replaced with a rca terminal for digi-in?

The optical in on the JB3 seems to only have 3 pins to connect.  Seems like it would be easy to desolder and remove existing optical jack and replace with digi-in RCA jack.  Most RCA jacks are two pins (i think).


 

Also found this product.which would accept both.  Took apart the JB3 and there seems to be plenty of room to install.

http://www.jalco.co.jp/04product/04pj/pj06.html


Has anyone had experience with de-opti modding a JB3? 

Any ideas?  Anyone already done this?

Thanks,

Kevin

The simple answer is NO, it can not be converted. You need a converter chip to make it a digital INPUT.

[KLowe]

  I dont want to make it a digital out.  But a digital IN.  I think I know what you are talking about...but im not sure.  Could you explain?

aren't the light impulses (IN) converted to a digital signal once in the NJB3? 


edit:  Maybe term RCA caused confusion.... SPDIF digi (not analog).... like digital out from a UA-5

[Church-Audio]

  I dont want to make it a digital out.  But a digital IN.  I think I know what you are talking about...but im not sure.  Could you explain?

aren't the light impulses (IN) converted to a digital signal once in the NJB3? 


edit:  Maybe term RCA caused confusion.... SPDIF digi (not analog).... like digital out from a UA-5

I know exactly what your talking about and the INPUT of the JB3 is optical not spdif you need a converter chip to make that switch its more then just a connector.

[caymanreview]

and the output of the JB3 is optical

dont you mean input?

[Church-Audio]

and the output of the JB3 is optical

dont you mean input?

Hehehe input yes

[caymanreview]

i remember alot of talk about this subject back in the day when we first started using jb3's alot. no one ever got this to work to my knowledge

[KLowe]

damnit.  I really want to UNDERSTAND this. 

From edirol UA-5 specs page.

Interface
    
      
USB
Digital input/output
Coaxial type
Optical type
(conforms to S/P DIF)
Connectors
    
      
Input Jack 1/2 (XLR type (phantom power), 1/4 inch TRS phone type)
Input Jack 3/4 (RCA phono type)
Digital In Connectors (Coaxial type, Optical type)
Digital Out Connectors (Coaxial type, Optical type)

And then from wikipedia definition of SPDIF:

S/PDIF was developed from a standard used in the professional audio field, known as AES/EBU which is commonly used in Digital Audio Tape (DAT) systems and for transmissions in professional studio recording. S/PDIF remained identical at the protocol level, but changed the physical connectors from XLR to either electrical coaxial RCA jacks or optical TOSLINK, both of which cost less and are easier to use. The cable was also changed from 110 Ω impedance balanced twisted pair to the already far more common (and therefore compatible and inexpensive) 75 Ω coaxial cable, using RCA jacks instead of the "BNC" connector found in broadcast television. S/PDIF is, for all intents, a consumer version of the AES/EBU format.


I'm a total newb at all of this digital audio stuff but I'm trying to learn.  Speaking in terms of a UA-5  the digi-out code is SPDIF right?  RCA and Optical. 
At the level of output from the UA-5 SPDIF leaves as an electical impulse (either through RCA or Converted to optical-toslink).  At the level of the JB3...the "optical in" receives the SPDIF vial Toslink and is then converted back to electical impulses SPDIF before it is recorded right?... so why can the three pins on the JB3 be replaced by the three pins of the above device?

Thanks for the help.  Just trying to UNDERSTAND this stuff.

Kevin

[KLowe]

I know exactly what your talking about and the INPUT of the JB3 is optical not spdif you need a converter chip to make that switch its more then just a connector.

but isn't the "optical input" written in the SPDIF format?  SPDIF can either be sent via coax cable or optical (Toslink).  SPDIF is just the code.


NO Wait....never mind.  (from M-audio website)

What are these for? Many new audio devices have built in digital audio Inputs and/or outputs, the trouble is that many have a Toslink (or mini Toslink) fiber optic connector and many others have a "Coax" RCA jack connector. The coaxial connection is referred to as S/PDIF (for Sony/Philips Digital InterFace) and uses a 75 ohm "video" cable (typically RG59) and standard "RCA" connectors like those of your stereo connections. Optical connections are called Toslink (Toshiba link) and usually use a squareish looking connector, with a centered round fiber optic "connection". How do you connect them? You use a converter. Also, for some reason most Surround sound receiver have a single Coax input and several Toslink inputs. What do you do when you have several components with a Coax S/PDIF output? You need a converter so you can convert the Coax to Toslink so you can connect it to one of the Toslink inputs of the receiver.

This shit is confusing.



apparently one guy has performed an internal "optical in" to "coax in" conversion  http://www.minidisc.org/digcoaxin/index.html .

I couldn't dream of doing this.  Fuck it.  I'm just gonna buy an R-4 or something.........

Thanks for playing.

[KLowe]

I know exactly what your talking about and the INPUT of the JB3 is optical not spdif you need a converter chip to make that switch its more then just a connector.



but isn't the "optical input" written in the SPDIF format?  SPDIF can either be sent via coax cable or optical (Toslink).  SPDIF is just the code.


NO Wait....never mind.  (from M-audio website)

What are these for? Many new audio devices have built in digital audio Inputs and/or outputs, the trouble is that many have a Toslink (or mini Toslink) fiber optic connector and many others have a "Coax" RCA jack connector. The coaxial connection is referred to as S/PDIF (for Sony/Philips Digital InterFace) and uses a 75 ohm "video" cable (typically RG59) and standard "RCA" connectors like those of your stereo connections. Optical connections are called Toslink (Toshiba link) and usually use a squareish looking connector, with a centered round fiber optic "connection". How do you connect them? You use a converter. Also, for some reason most Surround sound receiver have a single Coax input and several Toslink inputs. What do you do when you have several components with a Coax S/PDIF output? You need a converter so you can convert the Coax to Toslink so you can connect it to one of the Toslink inputs of the receiver.

This shit is confusing.



apparently one guy has performed an internal "optical in" to "coax in" conversion  http://www.minidisc.org/digcoaxin/index.html .

I couldn't dream of doing this.  Fuck it.  I'm just gonna buy an R-4 or something.........

Thanks for playing.

[Brian Skalinder]

but isn't the "optical input" written in the SPDIF format?  SPDIF can either be sent via coax cable or optical (Toslink).  SPDIF is just the code.

I believe so, yes.  Both the coax/RCA and optical/toslink outputs of the UA5 deliver a S/PDIF format signal.  There's a blurb from Todd R in the JB3 FAQ about some of the challenges with replacing the JB3 optical input with a coax input.