I can't say that I am very impressed with the hd800s on the miracle. I do not notice much change, or any, in the tuning when altering the voltage. I think the iem Hisenior mega 5 est performs to a much higher level on the machine and they are half the price of the sennheiser. I fear the review quoted above hit the nail on the head. Its a pity I did not see this review prior to purchase, and I state again that I feel that the Onix miracle advertising is not honest, or perhaps I should say grossly misleading, and I am surprised by a comment made by
@Shanling regarding the hd 800s. Perhaps things will change, after all I have only had the miracle for 2 days.
I think the hd800s are a difficult load and I suspect the miracle is underpowered, as indeed are a lot of headphone amps on the market.
The hifiman Arya stealth sound more at home with the miracle, I suggest Onix put this, instead of the hd800, on their brochure.