According to Quad a max of 100w is required. Am using a CJ 70S rated at 70wpc(configured for 8ohms) with the 2905s. Quite often with the preamp( CJ CT5)showing a gain of 60db,the self protection circuit kicks in and one of the speakers shuts off. This is easily overcome by reducing the gain by 1 or 2 db. In other words the Quads don't play really loud and don't like or require loads of power unlike the MLs or Maggies. My earlier speakers, the ML Odysseys would'nt sing at less than 75wpc. Sam Tellig was quite right in his review(Stereophile 06/07)that 50wpc is enough for the 2805s.
Cheers
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