Nobsound Headphone Amplifier Earphone Pre Amp Review

Nice little amplifier, very little heat. Didn't notice much low frequencies (<100Hz) for the first few hours and decided to swap out the tube for an old Russian 6N3P tube for $5 on ebay. It's now my favorite addition to my desktop.

This is my second experience with the Nobsound NS-02 tube headphone amp. by DukeAudio. After purchasing the Nobsound Little Bear FU32 (832) I checked out Revain and found that the seller DoukAudio had another nice tube preamp at an affordable price, so I bought this to add another experience to my mini music system. It works with any headphones without any problems and can be easily connected to an amplifier via a line-out. But I regret that DoukAudio didn't include a 3.5mm cable like they did…

I am using this amp with a GE JAN 5670 tube. I find it goes well with my Beyer DT990 Edition 600 ohm. The GE tube warms the sound only slightly, and that's enough to take the edge off the DT990's high frequencies. Also a good combination with Senn HD6XX. It's like almost unlimited power as it drives both at 9-10 on the volume knob. I plan on replacing the op amps in the future when I can get some Burson tubes. I tried some other tubes and really liked the Raytheon JRP 5670WA ring getters…

I just listened to these few tracks with Sennheiser HD 650 headphones. My source is a 320kb MP3 file from an LG G7 phone with the DAC built in and enabled. I have a hard time describing the tube sound other than giving silky smooth high frequency response, removing harshness and adding dimension to the high frequencies. The bass also has a nice "fullness" feel. Using it as a headphone amp increases my headphone listening enjoyment. The unit itself seems solidly made, I cranked the volume all…

UPDATE: 3 months. cheap DAC, cheap preamp and high quality tubes failed. The iFi Zen Dac is $129 and the Fluance i40 is way better than my experiment. CLIPIT is my phone DAC now, worth the money and sounds really good with my JBL headphones. Nobosound is not worth the money. If you haven't heard of budget iFi, you're going to love the Nobo. If it breaks, you might feel like an idiot, just like me. UPDATE: After 2 months this preamp broke. The Russian NOS didn't cope with any bass frequencies…