Phatlab Sassy Triode/Hybrid Solid State Headphone Amp

Ever since the debut of Sassy in 2015, everyone is astonished by its energetic performance accompanied by rich and warm sound of valves. Sassy can handle most planar magnetic and high impedance headphones by its uniquely designed tensionless hybrid topology. But there are requests from enthusiasts who hope to enjoy same sound quality and compactness with their favorite earphones. Introducing the Sassy ll, born on the expectation of many enthusiasts and beyond.
Functionally, Sassy II is equipped with a gain switch compared with Sassy. It is easy to implement gain switch in an OpAmp topology by simply changing the feedback ratios. However, it also changes the transient characteristics of amplifier that leads to sound quality changes. On the contrary, it is not easy to add gain switch in Sassy's full discrete and zero global feedback topology. It took our engineering team months of trial and error to find the perfect solution. The mechanical switch is outside the signal path to ensure no deterioration of signal integrity and S/N ratio. We have achieved the same sound quality between two gain settings. Considering the large difference in sensitivity between general headphone and earphone, we have chosen a -10dB for low gain mode. By lowering the gain, the noise floor is also 10dB lower and there is no trace of audible noise even with most sensitive earphones.
Specifications

Frequency Response 10 Hz – 100 kHz Output power 180 mW + 180 mW (300 ohm) 1000 mW + 1000 mW (30 ohm) Headphone impedance 30 ohm – 600 ohm Power supply 5V/1A via micro USB port Operation time (on battery) Approx. 10 hours (depends on headphone impedance) Charging time (>1A supply) Approx. 3 hours Dimensions 119 mm x 93 mm x 23 mm Net weight 270 gram