for this application, i would suggest a matched stereo pair of telefunken ELA M251s, running through manley vox boxes. digital tracking may not be adequate here, so you will need to use a studer 2" analog tape machine at 30ips (note: do not use any noise reduction). i would also suggest letting a professional do your mastering on a project like this.
Let's start here: What kind of equipment do you have to record this project?
Otherwise try this:
1. Set up your mic and recorder in advance near the xylophone.
2. Play the xylophone and adjust mic and recorder for proper levels.
3. Press record.
3. Set your daughter before the xylophone and let her wail away!
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