High Quality Handheld Digital Audio Recorder

[shwaip]

My current place of work is doing analysis of babies crying, and I'm one of a few people looking for a high quality digital recorder. Currently, a really old cassette recorder is being used, and the cassette noise is audible on the recordings.

The recorder needs to be small and lightweight, so that it can be held comfortably above a baby. The quality needs to be very high, as the audio files are fed through a program which analyzes the spectrum of the signal. Price isn't really that big of a deal - this'll be funded by a grant, and the cost will be written into it. It should also interface easily to a computer - could be via a file transfer, internal/external card, or high quality digital output. Mono is fine.

[primesuspect]

I'm not entirely sure you'll find something that is of a quality that reflects actual research. The really good handheld digital voice recorders are more focused on storage space, ease of use, etc. I'd bet that you'd get MUCH higher sound quality with a handheld or boom mic of very high quality hooked up to something like a minidisc recorder. It would still be portable, and much higher quality.

[shwaip]

Cool.

Another big issue is that it has to be able to be used by people who have no idea what to do with any type of technology, as the people gathering the data have pretty much no idea how stuff works - it needs to be along the lines of push record, make baby cry, press stop.

[primesuspect]

hahah how does the "make baby cry" part work? :wtf:

:nudge: :bawling:

[shwaip]

there's some official name for the tool I'm sure, but it basically "snaps" the bottom of the baby's foot with something, and then the baby cries. Usually, at least. Some of the ones I was copying from the tape didn't cry at all.

[primesuspect]

:eek:

being a baby sucks! ;D

[Thrax]

I'd like to take this moment to drive this topic further off course:

Why would you analyze babies crying?

[shwaip]

I'm not exactly sure why we're looking at it (likely related to taking anti-depressants during pregnancy), but here's what google has to say.


Changes in frequency, amplitude, length of cries, and resonance provide useful information for detecting diseases and disorders.

Overall, studies have repeatedly shown that infants at medical risk (like premature babies), and infants who have been exposed to lead or drugs, cry at a higher and more variable frequency than normal, but at lower amplitude, and with short utterances. These types of cry signals point toward a capacity problem in the respiratory system as well as an increased tension and instability of neural control of the vocal tract.

High resonance combined with mode changes indicate greater risk of Sudden Infant Death Syndrome.

http://www.futurepundit.com/archives/002779.html

[drasnor]

When I was in an Orchestra we used a handheld studio microphone and a hi-fi portable tape recorder; it worked pretty well. Are you sure the noise is casette noise and not just your microphone picking up the air conditioning, flourescent lighting, etc.?

-drasnor :fold:

[shwaip]

I can't be sure that it's cassette noise, but I wouldn't doubt it, as the recorder is fairly old. The other problem with the cassette is that after it gets recorded onto the tape, it has to be digitized for the cry analysis program, so it ends up getting input through the line-in on a computer with a cheap radioshack adapter (phono to mini). Sound quality could probably be significantly improved with higher quality capturing - but the system is old and cumbersome anyways (fairly heavy, cords everywhere), so an upgrade is needed.

[primesuspect]

I think your best bet is high quality handheld mic plugged into a minidisc recorder. That solves the digitization problem and will provide you with high quality sound.