Question RE: Light Pipe Fiber Optic connections

Question RE: Light Pipe. I want to insert an 8-channel Alesis DEQ830 Graphic Equalizer between the 8 (-10dB) outputs of a Dolby 7.1 Surround Sound pre-amplifier and the 8 (-10dB) inputs of an 8-channel power amplifier. The pre-amp & power amp are physically just a few feet apart. The 'hitch' is that I need to mount the DEQ830 approximately 30 feet away from the 8-ch pre-amp & 8ch power amp. I want to utilize the 'ADAT Optical In' connector on the back of the DEQ830 to receive the signals from the 8-audio output channels of the Dolby 7.1 pre-amplifier via a Light Pipe Fiber Optics Cable. On the return side, I want to utilize the 'ADAT Optical Out' connector on the back of the DEQ830 to send the signals to the 8-audio channel inputs of the 8-ch amplifier via a 2nd Light Pipe Fiber Optics Cable. Question: Can I use a single Alesis ADAT AI3 20-Bit Analog-Digital Interface mounted near the analog 8-ch preamp & 8 ch-power amp to facilitate this need? Specifically by: 1) connecting 8 short analog cables from the 8 outputs of the pre-amp to the 8 Analog Inputs of the Alesis AI3, 2) connecting 8 short analog cables from the 8 outputs of the Alesis AI3 to the 8 Analog Inputs of the power amp, 3) connecting a 30 ft Light Pipe cable from the 'ADAT Optical Out' of the Alesis AI3 to the 'ADAT Optical In' of the Alesis DEQ830, and 4) connecting a 2nd 30 ft Light Pipe cable from the 'ADAT Optical Out' of the Alesis DEQ830 to the 'ADAT Optical In' of the Alesis AI3?
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  • The ADAT spec is 5 meters - about 16 feet.
    You may be able to get away with a longer run , but you're pushing it especially if you're not using high end cables not to mention other issues.

    Look into/Run an extender like this one,you wont have to worry about signal degradation,bad connectors, breaking a long cable etc.You can then spend your money on purchasing shorter High Quality ADAT cables for use in a rack setup etc and be running standard Cat5e between hubs and Cat5e is dirt cheap

    http://www.heartechnologies.com/acces...

    Sweetwater has a sale for 125.00 each (In/Out)
    IN
    https://www.sweetwater.com/store/deta...
    OUT
    https://www.sweetwater.com/store/deta...
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  • Not out of the woods yet... I connected the Alesis AI-3 in the configuration shown in the previous diagram. The user manual for the Alesis AI-3 20-bit Analog-Optical interface clearly states that the maximum APF cable length that is recommended is 10 meters (or 33 ft). The manual further states that Alesis sells optical cables up to 5 meters in length (but this does not mean that a cable longer than 5 meters won't work). I am using a 30 ft optical cable from the 'optical out' of the AI-3 to the 'optical in' of the Alesis DEQ830 and a 2nd 30 ft. optical cable from the 'optical out' of the DEQ830 to the 'optical in' of the AI-3. I am receiving good signal on the DEQ830 from the AI-3 (all 8-LED ladders on the DEQ830 are jumping) but I am not receiving any signal back to the AI-3 from the DEQ830 (the 8-signal present LEDs on the AI-3 do not illuminate at all). When I increase the volume of the 8-channel Dolby Digital 7.1 processor, several of the Alesis AI-3 signal LEDs start to flash but still NO audio output from the 8-channel audio power amplifier. The Alesis AI-3 user's manual makes mention of using a common 'master clock' on all digital devices that are connected but there is no digital clock setting on the Alesis AI-3 or the Alesis DEQ830. I assume that two devices from the same manufacturer would sync. Help! I seem to be stuck...
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  • I just purchased 2 shorter optical cables. They are 6 ft long. I connected one 6ft optical cable at a time & tested the results. (1-6ft optical w/ 1-30ft & 2-6ft optical cables) I also switched the send/return positions of the two optical cables. I heard some clicking noises but but at no time did I hear even a hint of audio. (and yes, the audio power amp is turned on; I can hear the typical minimal high frequency hiss coming from the tweeters). Again, the 8-LED signal ladders on the Alesis DEQ830 8-channel Digital EQ bounce normally but only 2 or 3 of the signal present LEDs on the Alesis AI-3 illuminate (and these 2 or 3 LEDs on the AI-3 only come on when I turn the volume of the Dolby 7.1 8-channel analogy preamp all the way up.
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