As posted by Win Wenger to the imagestream mailing list 1:

Decades ago, I greatly added to the articulate intelligence of one of my own daughters, and several neighborhood children, while they were in the late pre-verbal, babbling or echolaic stage of development, through the simple device of feedback. I rigged two reel-to-reel tape recorders so that between them, the sounds the babbling child made would be broadcast back to the child after some seconds' delay, in a continuing loop. (The optimal delay appeared to be about 20 seconds.) For how long at a time to play the game and/or to let the machine run? - About 20-30 minutes at a time seemed best to me though the children usually wanted more.

This effect is now yours to use, for your child, at http://babbleback.sourceforge.net. This listgroup's own Brian Theado has set this up in such a way that you can plug a microphone into your own computer and download a program which will serve YOUR child as my clumsy mechanical reel-to-reel did mine. The child should forever after for a lifetime enjoy clearer, more articulate command of spoken language. That effect should also spill over into thought processes and into other forms of language usage, as well as into the verbal component of I.Q.

If your own child isn't at the babbling age, please bring this new resource to the attention of friends, neighbors, and kith and kin who do have children at this age.

This system is thought to be of use only for children while they are approaching or in the babbling echolaic stage of development. "Window of opportunity," so to speak.

This system has been made available to you free of charge. Project Renaissance profoundly thanks Brian Theado, the creator of this device, for this significant advance in the human condition.

The original article on the babbleback machine is posted under the title "Readiness" at http://www.winwenger.com/part27.htm The information and download on the new, free and easy electronic computer-based version of babbleback is posted for you at http://babbleback.sourceforge.net