I doubt that Sony will come out with a PCM-D1-like-thing with XLR inputs anytime soon. Sony makes an XLR adapter for the D1 and the D50 called the XLR-1.
For sound quality, I would expect you would get better sound quality with a Sound Devices 702 and a good stereo microphone. The trouble is that a 702 is $1875, and a good stereo microphone like the Sennheiser MKE-44P is $700. You also need to buy additional wind protection for the mic, a case for the 702, additional batteries, etc.
The PCM-D1 is nice, but if I were spending the money I would get the Sony D50 instead. I don’t think the PCM-D1 has any sonic advantage over the PCM-D1. As far as I know the only difference is the really nice looking VU meters on the D1.
The D50 is more compact, which is good, and the microphones sound great. It’s true, the Sony D1 and the D50 have a lower noise floor than other portable digital recorders (not including Sound Devices’ offerings).
I’d get a D50 and the Sony AD-PCM1 windscreen for nature recording, and a pair of Sony MDR7506 headphones for monitoring. It’s a small kit, and it will kick butt. You can pay a lot more, and get a great sound too, but the results you can get with the D50 will likely be just as good. Plus, since it’s small and all-in-one, you’ll be able to pull it out and start recording quickly, as opposed to having a 702 with an external mic.
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