One of the things I love about Sound Devices is that are always listening to user feedback and continuing to improve there products. The 664 was a great product when first released and is now an outstanding product because of continued firmware improvements. It is the best machine I have ever owned or worked with it. It truly blends the best of a ENG Mixer and a Recorder. The two latest firmwares 1.5/1.6 have added many great features including outdoor screen brightness mode, solid meters and indented left tone. If anyone has 664 questions feel free to email me
Sound Devices 664 Continues Improvement
Pro Location Sound LLC 
Should i buy the 552 or the 664 ?
i have the budget for the 552 but i could save up some more cash and get the 664.
i am currently looking to produce my own low budget short, is it over kill investing in the 664?
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All depends on your needs. If you need a machine that can multi track and generate timecode then save for a 664. If most of your work is DSLR or to full size cameras and you don’t need timecode or multi track but just a quality stereo back up then 552 is fine.
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