Fosi Audio N3 Headphone Amp

The Fosi Audio N3 headphone amplifier is a sleek little amp that packs a nice punch. The device itself is only 3.5”x2”x0.5”. It’s small enough to fit in that tiny little watch pocket on your jeans. The design is light weight and the body is rounded on the corners and edges, which makes it easier to slip in and out of your pocket.

Upon receiving this item, I was quickly impressed with how well it was packaged. Fosi Audio always does a great job protecting their product during shipping. Inside the box were the amp, charging cable, and instruction booklet. Pretty simple.

I was happy to discover that the amp was almost 3/4 charged upon arrival. So I didn’t have to wait for it to charge in order to test it out and see how it performed. It was ready to go. But charging is of course super simple. Just plug the usb C into the device and then the other end into a usb charge port. The indicator lights on the side tell you how much of a charge the device is holding. Once all four lights are illuminated, it is fully charged and ready to go.

During the initial testing, I used this device for about two hours and it only dropped one light level leaving the device at 3/4 charge. I have yet to exhaust a complete charge and am using the amp as I type. Clearly it will be able to provide several hours of music without requiring a charge.

Let’s get into the device operation. This thing is so easy to use. Just turn the device on with a press of the power button and it automatically goes into pairing mode. Find the device in you phones bluetooth setting and there you have it. Plug in your favorite headphones and you’re ready to go.

The N3 also has an aux jack if you have a device that isn’t bluetooth capable and switching over is as simple as tapping the power button once. I did not have a device that I could connect to test that feature though. The power button is also used to unpair by tapping twice and holding the power button for two seconds turns the device off. If you don’t unpair and just turn the device off, it will automatically connect to your bluetooth device when you turn it on again. The device unpairs as designed.

Now onto the good stuff. The N3 has a nice punch that definitely boosts volume on its own. But the N3 has bass and gain switches. While the overall volume is solid without engaging these switches, switching the gain toggle gives a substantial volume boost and retains, if not improves, overall sound quality. The sound was very clear and balanced. Definitely one of the best features on this device.

The bass switch also adds a punch and brings the low end forward. Both switches add improvement to sound and volume. The only thing that would improve these features is if they had incremental controls versus just an on/off switch. As someone who prefers a mid level bass that feature would be nice. The gain switch, however, will be on at all times.

As far as the volume dial goes, it is nicely situated in the top corner of the device. Its not too loose and not too tight and has a good range. The volume never accidentally adjusted while the device was in my pocket even when I was actively moving around and doing things. The only time the volume accidentally adjusted was when I was reaching into my pocket to retrieve the device. Other than that, the volume stays where you set it.

As far as the connection goes, I had no issues in my home. I live in a single level ranch and was able to go through my whole house freely. The only time I lost connection is when I was at the far end of the house a good 25 feet away from my phone. But if you keep your phone on you there will be no issue.

When testing the N3 I used two sets of headphones while using my iPhone as a music source. I started with my over the ear stereo headphones and then also used standard issue iPhone earbuds. Comparing both sets directly connected to my iPhone prior to connecting to the N3.

Starting with my stereo over ear headphones directly connected to my iPhone, the sound was clear and balanced but with no real power. Top volume was manageable without discomfort. Once connecting to the N3, my stereo headphones really started to perform. As mentioned earlier, the gain switch packed an impressive volume punch. The bass switch also gave a solid increase, almost too much for my preference. Top volume was much more than I could handle. Next I did the same with standard iPhone earbuds. I was impressed how much the N3 made a standard set of earbuds perform. They were surprisingly clear and powerful at high volume. The bass was a little more toned down in the earbuds but still there. It just goes to show that the N3 can make even the simplest of earphones perform like high end.

Overall, as an amplifier, the N3 is a very solid headphone device. It adds a serious volume boost that is clear and balanced. The gain and bass switches add a serious punch to the sound. Both beef up the overall sound and switching them on is my preferred listening mode. Again, incremental adjustment would be beneficial but having the option for control at all is a nice perk and definitely adds to the quality of the N3. There is a slight hum when the N3 is on with no sound coming through but that goes away when you turn on your music.

For what it is, it is an impressive device. Not completely sure on the cost but I believe they are available for about fifty dollars. If you are someone that has corded headphones that you really like or just want to get the most out of the standard earbuds that came with your iPhone then this is a nice way to do just that. Otherwise, the question would be, does it make more sense to just invest in a pair of quality bluetooth headphones. The major factor there would be price difference. The N3 might save you a little money over bluetooth headphones. I will say however, that I am very impressed with its performance overall.