have just done a side by side (i know its early but they are fully carbed) and they are so similar yet so different.
3068 - big aroma, massive notes of old bananas, some clove, has given off a little malt flavour but it is somewhat taken over by the yeast flavours and aromas
3638 - slight banana, bubblegum / caramel aroma, caramel / bubblegum and malty flavour, tastes a bit more balanced, and alot more sessionable than the 3068.
here is the recipe i used for the side by side, (i know you hefe gurus will be onto me but i also did it with 3944 which i have done before and loved and made 10lts of it and 5lts of the other 2)
Recipe Specifications
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Batch Size: 23.00 L
Boil Size: 31.41 L
Estimated OG: 1.051 SG
Estimated Color: 6.6 EBC
Estimated IBU: 16.6 IBU
Brewhouse Efficiency: 75.00 %
Boil Time: 60 Minutes
Ingredients:
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Amount Item Type % or IBU
2.50 kg Pilsner Pale Malt (Barrett Burston) (3.9 EGrain 50.00 %
1.50 kg Wheat Malt (Barrett Burston) (3.0 EBC) Grain 30.00 %
1.00 kg Wheat, Torrified (3.3 EBC) Grain 20.00 %
10.00 gm Saaz [4.00 %] (60 min) Hops 4.2 IBU
10.00 gm Northern Brewer [8.50 %] (60 min) Hops 9.0 IBU
12.00 gm Saaz [4.00 %] (15 min) Hops 2.5 IBU
10.00 gm Saaz [4.00 %] (5 min) Hops 0.8 IBU
0.60 items Orange Peel, Bitter (Boil 5.0 min) Misc
5.00 gm Coriander Seed (Boil 5.0 min) Misc
1 Pkgs Bavarian Wheat (Wyeast Labs #3638) Yeast-Wheat
1 Pkgs Belgian Witbier (Wyeast Labs #3944) Yeast-Wheat
1 Pkgs Weihenstephan Weizen (Wyeast Labs #3068) Yeast-Wheat