Note: Oppo has since stopped making products, although they still support existing ones and will occasionally provide firmware updates. This is sad news as I considered some of their products (the ones I tried) to be among the best. These include their fantastic Oppo PM3 headphone, and this HA2 Amp that we’re about to review. You can still get your hands on one for a decent price, but please be careful who you buy from. You can also check eBay as well for some good deals!
Included Accessories: Power Supply Unit (Rapid Charging Charger)
USB A – USB micro-B data and rapid charging cable
USB A – Lightning data cable (for Apple devices)
USB micro-B to micro-B data cable (for Android and other smartphones)
3.5 mm – 3.5 mm stereo audio cable
Silicone rubber band (2 pieces)
User guide and warranty documents
Built-in Battery type: 3000 mAh lithium polymer rechargeable battery.
Battery Operation Time: Approx. 13 hours for analog source via Audio-in; approx. 7 hours for digital soruces via USB
Charging Time: Approx. 1 hour 30 minutes.
To put it bluntly: The HA-2 is the real deal. As you may know from my other articles, I frequent my local Audio Advice weekly, and sometimes up to multiple times per week. I’m always in there demoing headphones, A/B testing, and taking notes.
Being there so often has allowed me to interact with the guys at the front desk, and more specifically a guy named Chip. Chip is one of their Home Theater specialists, and he really knows his stuff. On top of that, he’s one of the most genuine, personable, and helpful people I’ve ever come across. He’s always down to discuss audio, and it really makes me feel special when he asks ME about my opinions on stuff that has to do with the Home Studio, Headphones, Amps, etc.
We got to talking about the HA-2, and he offered to loan it to me for about a week a long with the Audioquest Dragonfly Red.
Both are absolutely exemplary. The HA-2 is a bit more expensive but it’s worth every penny.
Because I said so. Just kidding. There are a couple of reasons, my friend.
First off, the HA-2 will work with the majority of headphones, and generally it ranges from 16 Ohm – 300 Ohm impedance cans. So yeah, pretty much everything. 😀 What is Headphone Impedance?
The second reason is because it’s output impedance is so low (less than 0.5). This also essentially means that the HA-2 will work with nearly everything you throw at it.
To give you a quick example: My Sennheiser HD600 has an impedance of 300 Ohms and a Sensitivity of 97 dB. In short, it’s power hungry, but will work with the majority of amps. Because of it’s higher impedance, it requires more Voltage (power), but also a fair bit of current given it’s on the cusp of what’s considered low for Sensitivity. What is Sensitivity in Headphones? Anything below 97dB needs more current and anything above generally needs less.
How much power does the HD600 need? 20mW to be exact. The HA-2 provides 30mW into 300 Ohm, so it just makes the cut here. Learn more:Sennheiser HD 600 Review.
You can see that 300 Ohms is just about the ceiling for this amp. Being that I wasn’t familiar with the specs, I honestly did not think that the 600’s would sound their best out of the HA-2. I was proven wrong overwhelmingly.
Build and Style
This baby is about as sleek as it gets. It’s extremely attractive and elegant looking, with a rock solid build. When I got my hands on it I didn’t want to ever let it go. It’s that sexy, and just feels really good in your hands. It’s also got one of the most perfect volume knobs that I’ve ever had the pleasure of turning.
If the HA-2 were a female, it would be a mature, intelligent, sexy, and ambitious woman like Keri Russell. For sure.
Input Ports: Analog: 3.5mm stereo audio-in. Digital: USB A for iPod/iPhone/iPad; USB micro-B for smartphones with USB OTG feature and computers.
Not only is it sexy, durable, and compatible with nearly all headphones, it’s also extremely versatile. You can:
Use it to charge your phone. Press and hold the button just under the 4 LED lights to activate.
You can use the line-out jack to a separate amplifier.
You can use it with your phone, effectively bypassing the crappy internal DAC in favor of the HA-2’s amazing one.
You can use it with your laptop via USB.
The best part about this thing is the way it makes your headphones sound. I was floored with the amount of extra detail that I had been missing, and it never comes across in a way that seems forced, harsh, or bloated. It’s one of the smoothest, crispest, most enjoyable experiences I have ever had with an Amp, along with the Dragonfly Red and Schiit Magni 2.
Stu is determined to provide the truth about all things audio, and strives to deliver excellent content to you the reader! In his spare time, he likes to fish, paint, play guitar, attend church, take photos, record videos, graphic design, and more. His attention to detail and perfectionist attitude are what allow him to excel, but it can be both a blessing and a hindrance at times.