“ Without referring to "He-Who-Must-Not-Be-Named's" (A.K.A. NwAvGuy) blog, and speaking from my own listening experiences, I really do think the Objective 2 is a great headphone amplifier. No, I don't think this is the amp to end all amps, but it's a dang good one and it only cost me $156 USD (which includes the Triad brand WAU12-200 AC adaptor). In fact, it can be found...” --miceblue
“Introduction A bit of preamble - I bought this C5 amp to go with my FiiO X5ii and Fidue A73 set up. The idea was to get the amp to reduce the noise floor and offer a bass toggle for when I felt I needed it. I wasn’t expecting (or needing) much of an improvement in sound quality or sound signature. I'd asked for advice on Head Fi forums, but had no responses. I’ve since be told...” --mellowjamie
“ At the time this review was written, the JDS Labs Element was for sale on their website. Here is a link to the product which also explains their specifications and features: https://www.jdslabs.com/products/151/the-element/ Introduction Not too long ago, I had a chance to review Zach’s flagship headphone, the ZMF Omni. Here is a link to the review: ...” --Hisoundfi
“JDS Labs c421 Headphone Amplifier (OPA2227 chip choice) I was never intending to write a review on the c421. In the fast moving, ever changing, expensive and high-risk land of portable audio amplifiers the c421 is ancient. Weighting in at 113 grams, and coming from year 2012, this little guy could easily get swept under the carpet and forgotten about for all of time. In terms of...” --Redcarmoose
“This was provided to me from JDS Labs as a free review unit, so I need to give a big, big, big thank you to JDS Labs for their generosity! You might be able to see in the photos that my unit has some blemishes in the aluminum case. These will not appear in normal units. Since Head-Fi doesn't display the rating details from the reviewer, but rather the community average, here are my...” --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
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 ...