Kevin,
I'm not quite to the sound engiineer level at all but have you tried a software approach to adjusting sound after capture? I know you can adjust sound levels on the run in PD7 and quite similarly in Pinnacle Studio Ultimate. I know there's tons of tricks in Sony Vegas, Adobe Premier, and Liquid Edition as well.
Both my new Sony HDR-SR12 and my old Panasonic PV-GS70D have microphone inputs (the Panasonic even came with a Mic) and you can mount a Mic onto the Hot Shoe on top of both. Some folks use a Sennheiser ME64/K6 or a ME67/K6 on their SR12 with no problems. The K6 uses a AA battery to provide the 48v phantom power fro the mic.
I found a thread on another forum where the user stated: "I manage to get great results with it. I do not hear any hiss. So it works. I like both mics. The ME67 is a very long shotgun and can isolate sounds very well. The ME64 is better indoors and produces good ambient sound outdoors."
Another user on a separate forum said: "I have tried the Sennheiser MKH-416 through the Beachtek in to the SR12 and it is so awesome." A response said "Yes indeed the Sennheiser MKH-416 is a bit of a legend as far as mics go. Its used widely in the professional field and even movies etc. A long-lived shotgun mic that professionals rely upon."
(Maybe you've already got one on these?)
I think the Sony is a great consumer camera and perhaps a little less pricey. Perhaps you should add it to the list.
Regards,
Jim
Asus Z87-A Motherboard - O/C if needed to about 4.6 Ghz.
Intel i7 4770K CPU
16 Gigs Corsair Vengeance DDR3 Ram
OCZ 448 Gig SSD (for OS and related Video Editing Programs)
1 TB, 1.5 TB, and 3 TB Data Drives - Slide in Drawers as needed.
LG's HL-DT-ST BD-RE BH10LS30 Blu ray Burner
Samsung SH-S223F 16x DVD Burner
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