Quote: Absolutely true. The price is good but hard to find places to audition  

Rs1i HERE:)

Quote: Thanks man. I think I probably will go with the HDP. Because I plan to have Grado RS1i some months later. And,since they are both low impedence,high sensitivity headphones, is the DAC more important,since driving them in power is not that difficult?   

Also, what exactly the sound sig of HDP is . I found some people said that it's warm,while some say it's neutral with clarity?

Quote:   Thanks for the detailed reply !  My notebook actually does not have a optical out. Is there other recommendation?  Since HDP does not make much difference, is udac2 a good approach? Maybe I can match it with  Schiit Asgard.   But,then they are at almost same price.   

I am new to headphone. I have just bought the HD 598 a week ago. I found that I am fond of the large sound stage and clarity that it brought.  However, I just use my laptop to drive it (integrated REALTEK HD sound card), and I found from the web that a good DAC/AMP will definitely get the most...