Singing Mice and Brain Chemistry

Shirlockc writes "The Public Library of Science has a research article on how male mice actually sing in the presence of females. They actually posted some of the audios adjusted for human ears as these songs are ultrasonic. The authors are comparing these warbles to bird songs. The songs are quite complex so do the mice learn them and/or improve on them? This can be a potential model for investigating how brain chemistry works during learning."

Comments

Except for those pesky reconstruction filters

[wowbagger]

Except that even the cards with the 192kSample/sec DACs won't reproduce much above 20 kHz. Remember, in a proper design you have to follow the DAC with a reconstruction filter as your signal will have spectral aliases every Fs. The idea of running a 192 kSample/second rate is to allow the reconstruction filter to gradually roll off from 20kHz to the Nyquist frequency of 96kHz, rather than the rather sharp roll-off from 20kHz to 22.05 kHz you see in 44.1kSample/sec gear. You also avoid the sin(x)/x roll-off in the reconstructed audio, as the roll-off in a 96kHz Nyquist frequency system is still pretty flat at 20kHz.

However, if you wanted to experiment with this, you could try to find an old (and I do mean old) Zenith remote control from the 1970's - they used ultrasound rather than IR as modern gear does, at about a 30kHz frequency. You could then drive that speaker from a DAC on the printer port, possibly with a simple timer chip to create the sample clock so that the computer "thinks" it is seeing a normal printer on the interface (that way you can avoid a great deal of the latency issues, especially if you use a printer port with a hardware FIFO.) You could eliminate the reconstruction filter as the transducer will do most of your filtering for you. Failing that, here are some transducers that will Git 'R Done.