NuPrime HPA-9 Headphone amp – This headphone amp is a tad pricey for a headphone amp in my opinion, but still well south of four digits by hundreds and considering what you get, it’s got low diminishing returns, so it is still worth consideration indeed if you are really into headphones.
More info here: http://www.nuprimeaudio.com/index.php/products/dacs-and-headphone-amps/headphone-amp/hpa-9.html
Single End JFET input stage circuitry design provides the very good second harmonics. And provide high input impedance and ultra low input bias currents. As well as high S/R.
Non feedback output stage design provides low Temporal Distortion and natural sound.
Pure Class A headphone amp design.
Phono (RIAA) input module: Internal setting to MM or MC.
Supporting up to 3 headphones simultaneously.
Maximum headphone impedance support range from 8 ohm and up to 1K ohm. Although many headphones state that the nominal impedance is at 300 Ohms, however, during some frequency (100Hz for instance) the peak impedance is actually at around 700 ~ 800 ohm. The HPA-9 does not have such limitation.
DC offset protection.
1 x Phono Stage
2x Analog Stereo RCA
1 x 3.5mm earphone out
2 x 6.3mm headphones out
2 x pair of stereo RCA out
THD+N: < -110 dB (1 kHz / maximum gain)
Frequency Response: 0 Hz to 200KHz (-3dB)
Dimensions: (W x H x D): 235 mm x 55 mm x 281 mm
Weight: 5.5 pounds ( 2.5kg )
Worldwide AC voltage: (90VAC~130VAC // 210VAC~ 250VAC) With Voltage Select Switch