audio recorders

[Brian MacWhinney]

Fred,
   That's an important topic.  The quality of the recordings for things
like babbling is not so much a function of the recorder as of the mike, the
mike placement (pillows, etc), and the presence of extra noises in the
room.  There are a couple pages of discussion of this issue in the CHAT
manual (http://childes.psy.cmu.edu/pdf/chat.pdf) in Chapter 18 on recording
technique.  DAT, minidisk, and high quality cassette all work fine.  I'm a
little less clear about microphone type and selection.  I've used a
particular SONY model ECM-909A.  But other people may have done a
systematic study and found something better.  A markedly different approach
is to use small condensor mikes that broadcast to receivers.  Anyway, all
of this is in Chapter 18.  I would love to receive critical comments on
Chapter 18 from people who have found better techniques.
   Of course, there is always the sound-proof room approach, but then the
child may just decide that they don't like babbling in sound-proof rooms.
I wonder if babbling researchers have ever tried that approach.  We've been
receiving some very high quality babbling recordings now from Brosda and
Davis/MacNeilage/Matyear.  I wonder if they can give you details on what
worked for them.  I am happy to collect suggestions and modify Chapter 18
and perhaps add this to HTML web pages.

--Brian MacWhinney