Glad your 66 is singing pretty Greg! In another thread we were discussing drilling a hole in the power suppy of the 99 and I presume the 66 also.I went ahead and drilled a small hole and filled it with sand.It quieted the power supply to absolute silence and made the 99 as quiet as any solid state pre I have heard.Before anyone does this I urge you to contact Mark first for the basic instructions.
