“ 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
“This review is based on matching the Mini X with Hifiman He-500 Headphones. You may be reading this review, unsure what to make of this Amp, asking how can a cheap sub $200 amp offer the power needed for an expensive Headphone such as the Hifiman He-500? If you have done your homework you will find this is the stereo amp everybody is...” --fluidz
“ 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
“ ****Note**** As always, these are strictly my opinions. I try to present these products as honestly as possible and try to describe them as best as possible. As always, YMMV. ****NOTE**** FISCHER AUDIO MYSTIFY PORTABLE HEADPHONE AMP SPEC’S: Frequency “flatness”: +/- 0.5db Dynamic Range: 110 db Total Harmonic Distortion: 0.001% Intermodulation...” --LFF
UPA-200 represents a true breakthrough in audiophile-quality amplification. At last, a truly affordable stereo power amplifier that can satisfy the most discerning aficionado, and at the same, is affordable to anyone with a desire for real quality. Our advanced engineering and design techniques have resulted in an amazing new amplifier. Its rock solid performance and affordable price point...
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 ...
Frequency range: 10Hz-20kHz Amplitude-frequency responce (AFR) irregularity within the frequency range: 0.3 dB Dynamic range: 110 dB Harmonic distortions: 0.002 % Intermodulation distortion (CCIF) 0.006 % Interpenetration of channels at frequency 1 kHz: -73dB Rated input voltage: 0.5 Maximalinput voltage: 3.5 V Maximal output voltage at the non loaded output: 10 V Maximal undistorted power...