A. IV tube for output DAC chips balanced with the features and options: 1. Using the chip DAC output voltage as: ES9018, CS4398, FN1242, WM8741, WM8741 AK4397 ..., AK4397 2. Simple design, easy to carry. 3. Use high-voltage power supplies have a very small source impedance of about 0.001mR, small source interference. 4. Use 12Au7 and 6DJ8 tube. 5. Input and Output balance unbalanced, with my sound described as follows: very bright treble, and detailed, Mid-clear audio sound, clear, bass is full and deep. The sounds very lively space with music filled the room.