tcmay's comments on the use of DAT tapes to 'dub off' other recordings as the host-medium and to apply the signal to the low-end significant bits works out something I brought up earlier: checking the copy against the original. The idea of using a DAT tape as a mode of transport, however, doesn't appeal that greatly to me. To send a message, I have to pull out one of my prevoiusly recorded DAT host-tapes, then record over the 5th song with my mix of host/message pair, then fed-ex it (or hand-deliver it) to my target. If I take this signal and push it across internet, I no longer have the passive-looking DAT tape in my DAT music collection. Instead, I have a 900k sound file that I push across the net. Since the net is usually not used to push the latest Michael Jackson tune, it might raise a flag. Tim's comments are valid and definitely help solve problems on the physical level: now how about cyberspace? mt Matt Thomlinson University of Washington, Seattle, Washington. Internet: phantom@u.washington.edu phone: (206) 528-5732 PGP 2.2 key available via email or finger phantom@hardy.u.washington.edu