The Objective2 (O2) is an open source earphone amplifier created by NwAvGuy, with focus on benchmark performance and low expense. This product consists of a totally assembled and hand tested O2 amplifier, all set for use. You will only require an AC adapter ideal for your region.
The O2 has actually produced a stir in Head-Fi. org's do-it-yourself neighborhood. After being prohibited from Head-Fi for heated conversation, he continued to design O2 for optimum standard performance to prove his points. It's big and heavy, so barely worth consideration as a portable amp, however, O2 lives up to its name.
Gain: 2.5x and 6.5x
Frequency Response: +0.01, -0.01 dB (20Hz-20kHz)
Output impedance:0.5 ohm Volume Potentiometer Taper: 15A or 3B
Power:14-20V AC adapter with a standard 5.5 x 2.1 mm(not DC adapter). You can charge 9V battery inside from AC Jack and carry this amp.
Size: 108.50 x 80.00 29.50 x mm Weight: 311g Accessories: cleat rubber/adapter