“ I bought this amp for my Q701s (Which I won't receive until Friday). When it came I took it out just to make sure it works (All my current headphones are low impedance and don't require an amp). I hooked it up with probably one of the worst possible sources you can imagine: a Nintendo DS (I was in the middle of playing a DS game when it arrived). Of course there was volume, but I also almost...” --DSW92
“ Okay, a serious question not related to the review: what is the difference between the "Audio Quality" rating and the "Quality" rating, and how is the "Quality" rating different from the "Design" rating? *scratches head* Anyway, back to the review. I did a video review for the C5 on YouTube if you are interested in an auditory/visual...” --miceblue
“ The JDS Labs O2 + ODAC combo (and just about every other version) is built into a simple metal enclosure (mine is black) and all of the inputs and outputs, save for the USB input are located on the front of the device. Aesthetically, I don’t love that design decision but I understand it’s one that was likely made due to the O2 being designed originally as a portable (sort of)...” --TheGame21x
“Amazing sounding amp, easy to charge with a mini USB, bass boost works really well without muddying the sound, low/high gain switch. Sounds better than any other amp I have tried, ie Fred Fred cmoy and fiio e7 ” --Mkvy
C5D is a high-performance portable headphone amplifier featuring digital volume control, multi-position bass boost, dual gain, and asynchronous digital-to-analog conversion compatible with iPad, iPhone, and all UAC1 compatible operating systems.
Taken for item page: "The Objective2 (O2) is an open source headphone amplifier designed by NwAvGuy, with emphasis on benchmark performance and low cost. This item includes a preassembled and hand tested O2 circuit board, ready for use. You will also need an enclosure and AC adapter. The O2 has created a stir in Head-Fi.org’s do-it-yourself community. After posting one too many ...