If I am not mistaken AK4497 is the new Flagship DAC from AKM which was announced Last year, so massively produced it for commercially availability wouldn't be that immediate ? If so, SP1000 probably was Planned out during that 12-36 months period as you said, but the physical product wouldn't be possible until 6-7 months ago. Good thing is that none of us is seeing the pricing of $4500 or such, and probably thanks to Sony WM1Z ? Until then, only A&K was the most expensive and luxurious DAP to go for. Thanks to A&K for resurrection of the Flagship Walkman. I think I am living in a good time for music