Unit that will combine 4 stereo digital channels and output as one ADAT lightpipe?

[666666]

Let's say you have a recording device that only accepts a bank of 8-channels of AD/DA conversion via an ADAT lightpipe port... such as the Digi-001, 002, 003.

And let's just say you happened to have four separate 2 channel AD/DA converter units that you like to use (that had stereo SPDIF or AES/EBU, etc connections).

Does anyone make a digital router / mixer / combiner that would take four separate stereo digital sources (SPDIF or whatever) and output them all at once via an ADAT lightpipe?

Another way I am looking at this... is there any way I could hook up four separate 2-channel AD/DA units (such as HEDDs or Benchmarks or Lavrys, etc) and somehow send them into a Digi-001/002/003 via the Digi's ADAT lightpipe ports?

Any info, links etc much appreciated

[ZEUSS]

The RME ADI-8 DD could probably do this. Input the converters via AES and send them out Lightpipe. http://www.rme-audio.com/english/adi/adi8dd.htm