Is there a mass-market (a cheap module from china/taiwan/hongkong) equivalent of the OptoRec and OptoGen , which could be usefully hooked up to a few of these: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=230418195291 to make a useful multichannel D/A for an ADAT lightpipe ; the optorec could likewise be paired with external A/D's or used to "vampire" an I2S signal from external digital gear w/o digital outputs. Also, experience with assembling and/or using the OpenRec/OptoGen? http://electronics.dantimax.dk/Kits/Digital_audio/11329401182.html .................. OptoRec and OptoGen ADAT digital audio receiver and transmitter circuit These kits is [sic] an 8-channel interface circuit using the ADAT protocol. They supports the sample rates 44.1 and 48kHz and up to 24 bits. The boards can be used for adding an ADAT input to a DAC, an ADAT output to an ADC or for DIY projects. The receiver board includes an ADAT input, ADAT output, a wordclock input and I2S outputs. The transmitter board includes an ADAT output and I2S inputs. The kits use SMD parts, so some SMD experience may be needed to assemble the board. SOT-23-5 parts are used, so a fine-tipped soldering iron (or SMD tools) is needed. .................. It's that "SMD experience" needed part that really gets me. I will invariably get a blob of solder bridging two SMD pins, and then in the course of trying to correct my mistake manage to get it bridging a few more pins and melting the ic or lifting the pad of the pc board. there's a reason i went into software. The undo key.