I am looking for a small parabola for field recording because the one I purchased is too large to be easily transported. Do you have any recommendation for a practical small one ? I also heard about some people who were building them from scratch (using bird feeder dome cover). I am interested in any DIY ressources !
In addition to Michael's suggestion, I'd recommend the Wildlife Sound Recording Society (WSRS): https://www.wildlife-sound.org/
WSRS has a member's forum and I'm sure someone there would have ideas on DIY parabolas, or recommendations of small off-the-shelf models. Members have access to the archive of newsletters and articles as well - i think this topic is likely to have come up in the past. There is an interesting article on Parabolic Stereo in Resources > Equipment on the website. Nice bunch.