The FiiO AM2 is a replaceable/upgraded amplifier unit that you can use to change the sound quality of your FiiO X7. The FiiO AM1 (that is included with the FiiO X7) and FiiO AM2, have identical dimensions.
Where the FiiO AM1 has a brushed titanium appearance on the front and powdered titanium appearance on the rear, the FiiO AM2 is a slightly darker shade, and powdered finish on both front and back. Replacing the modules is extremely easy; simply using the Screwdriver that came with your FiiO X7 audio player it is merely a matter of undoing 2 screws to remover the FiiO AM1 and replace it with the FiiO AM2.
The biggest difference with this amp is really the voltage output, and slightly higher output impedance with the AM2, which is still impressively low 0.5 ohm. As far as power goes, the AM2 is able to produce triple the output into 32 and 300 ohms. It also has a higher peak voltage output. The FiiO AM2 unit comes in a metal protective box which will protect which ever amp you choose to store in there.
Voltage amplification: Muses02
Current Drive: Buf634
S/N (H/O): ≥118 dB (A-Weight)
THD+N (H/O): <0.001% (32Ω/1 kHz)
Output into 16 ohm: >350 mW (16Ω/1 kHz)
Output into 32 ohm: >300 mW (32Ω/1 kHz)
Output into 300 ohm: >30 mW (300Ω/1 kHz)
Impedance: <0.5 Ω (32Ω)Peak output voltage: >8.8 Vp-p
Peak output current: >250 mA
Channel Separation: >72 dB (32Ω/1 kHz)
Play time: 8 hours+
Dimensions: 64 x 25 x 16mm