Complex sentence: Naim never published technical specifications for this low-powered design, preferring to let the product speak for itself; trade speculation of its power output ranged from 5 to 15 watts per channel.
Split into simpler sentences: Naim never published technical specifications for this low-powered design, preferring to let the product speak for itself. The trade speculation of its power output ranged from 5 to 15 watts per channel.