Originally Posted by purrin
The ODAC, when it's working properly (with good USB power, which is hit or miss depending upon your laptop or PC) is a very very good DAC. The reason I don't wholeheartedly recommend it is because of its varying performance according to the power quality of USB ports.
I think people with mid-fi cans like the HD-600, HE-400, etc. will definitely notice. But as you mentioned, recording quality is crucial. Not really worth it if most of what we listen to consists of Japanese anime music soundtracks or odd-ball Pink Floyd dance remixes.
I used to own your current amp - the HR Microamp. It's probably one of the better ones in the HR lineup. The higher end HR stuff sounds like nasty nasty solid-state. However, my opinion of the Microamp is contrary to that of yours. The HR microamp sounds really closed in and kind of dead and boring. (Honestly, I'd take a CMOY / CHA44 with choice op-amps +/- 12 voltage rail sover it. I actually built one years go and dumped the HR Microamp afterward.) I figure this is due to differences in source and recordings.
Here's the weird thing for me.. the Vali and Headroom Micro Amp (+ Astrodyne) sound extremely similar to me. Basically the same. I did 10-12 A/Bs and same results. Same DAC and same cables. I've been looking for the closest match I could find to the Micro Amp sound and the O2 was the closest, but the Vali was even closer. Maybe when I described what I'd improve on the O2, the Vali and Micro Amp fixes all that. Slightly fuller mids and very slightly smoother treble. We're talking like a 2% difference
About the closed in sound of the Micro Amp... IMO the Micro Amp NEEDS the Astrodyne unit. I'm sure you used that or maybe not, but it's cheap. I also noticed that with the stock power supply it absolutely HATES MOV based surge protectors and i've never figured out why. I can actually hear it crapping up the sound with only my DJ100 and very warm or bassy headphones. Not audible on the Q701 and most open headphones unless you have golden ears.
I actually had noticeable improvements on the Q701 with the Astrodyne PS, but basically inaudible with my HD-650. I'd say the Micro Amp needs the Astrodyne to be at it's best. It is more analytical and clearer with the Astrodyne. Don't ask me why or how. Comparing it to an O2 without the Astrodyne does feel a bit odd. I can't say it's more than a 10% improvement though.
I know that for a whole year I complained that the Micro Amp had a slightly closed in soundstage (when I was new to all this) but it was actually my DACs fault! Not sure if you agree but the HRT MSII is very closed in, too warm and not really smooth sounding. Once I switched to the ODAC, Modi and Micro DAC it was fine.
You may think i'm nuts but I find the Micro Amp + Astrodyne to be my idea of a transparent amp and more so than the O2. It's weirding me out that the Vali sounds the way it does. Perhaps the Vali has more body to the sound, but I don't think so. The Vali's bass with my DJ100 is kind of loose/sloppy but maybe it's just a bad match. It's not that bad.
I really hate to say this but the Vali doesn't sound too colored at all and not dramatically far off from being what I think is transparent. Makes no sense to me!
OK, now I just want a solid state Vali, but even better.
Oh and I like "dead and boring" amps
Seriously the Vali is about as "fun" as my current amp which is a good thing. Both sound great with the modded Q701 (which you should try BTW).
The Vali and Micro Amp to me sound like a more fun version of the O2. I won't say more colored, but just more natural sounding in the mids/treble.
It'll be fun to compare them more because so far I like them both. I'm sure i'll find something I don't like on the Vali. Doesn't sound entirely smooth with my DJ100 but maybe just not a good match or it needs more use.
Edited by tdockweiler - 12/1/13 at 10:40am