As I contemplated a pair of Docter 8x56 Nobilems, I wondered if the 47 oz. weight would be too heavy. It's smaller predecessor, the CZJ 8x50 Octarem didn't seem burdensome at 45 oz. due to its excellent weight distribution. In fact, it seemed easier to hold than the 36 oz. Nikon 10x42 LX roof, with its more centralized weight.
As Ringo would say, "It's all relative, you know". The 29 oz. 804 Aududon normally doesn't seem that heavy for me to hold (only around my neck), but it can at times feel a bit hefty after using the 23 oz. 7x36 ED2, which feels like a "featherweight" due to its open bridge design.
The pre-SV El, another middle weight contender like the Audubon, felt lighter to hold than I had expected when I first hefted it, because I could wrap my hands completely around the barrels and support the bin from below, from the sides, and from above.
I concluded that ergonomics and the type of binoculars both play an important role in "felt" vs. actual weight.
How much weight can you comfortably hold with bins?
Closed bridged roofs? ______
Open bridged roofs? ______
Porros? ______
I can say this much, I can't hold as heavy a pair of binoculars as Arnold's mother, Aurelia:
http://www.thefader.com/ys_assets2/.../binoculars.jpg
Brock
Hello Brock,
I cannot answer your questions as posed because of a lack of experience, as I have had only one open bridge binocular, that featherweight.
However, I have a little trouble with an 8x50 Leica BA, a roof glass and no trouble with a Zeiss 7x50 Porro.
Aurelia is working with a Porro II binocular which usually has great ergonomics. Both the Royal Navy and German Navy favoured that configuration.
Happy bird watching,
Arthur 
Brock - For some reason I find roofs seemingly weighing more than porros of the same weight if that makes sense. I believe your singling out ergonomics as one of the important elements in actual versus felt weight is valid. Like you I have very large hands so the 7x50 Zeiss porro fits nicely. So does my Zeiss 15x60 BGT, but I must be resting my elbows on my knees with my rear end firmly on the ground for handling that kind of weight comfortably. And I believe a certain amount of mass is essential for steady viewing. My Nikon 10 x 70 is simply too heavy to hold with any degree of comfort with all that mass hanging in front. The binocular weight really becomes an issue with me when the binocular is slung around my neck. Then anything over 25 ounces is too heavy. I'm also a die hard porro fan.