Currently Being ModeratedMay 29, 2013 7:10 AM (in response to Acousticare)
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Thunderbolt cables should not exceed three meters for maximum performance. The Apple Thunderbolt to Thunderbolt cable (2.0 m) is two meters in length.
For more information on this, take a look at this article:
About Thunderbolt to Thunderbolt cable (2.0 m)
Hope this helps,