Frequency response of the Fireye Mini, in the left channel (blue trace) and right channel (yellow trace)
If you’re drawn to cute audio products, you won’t be able to resist the Fireye Mini. It’s a super-simple headphone amp sheathed in an impact-resistant rubber covering, with nothing but two 3.5mm jacks for input and output, plus a USB jack for recharging. Plugging a cable into the output jack turns on the power. Best of all, it comes in your choice of red, purple, green, black, or white. Minus the keyring loop, it measures just 1.4 by 0.9 by 0.4 inches.
The Mini’s performance was anything but mini. It reminded me of some of the old tube amps I’ve owned, with the same fat, satisfying sound. The treble is super-smooth, although it’s also a bit on the soft side. The horn-heavy jazz orchestral arrangements on Freddie Hubbard’s Hub-Tones tend to sound a little blarey through many IEMs, but the Mini mellowed them out nicely. However, on one of my favorite high-frequency tests, the acoustic guitar duet “Ms. Julie” from Larry Coryell and Philip Catherine’s Twin House, the soft treble gave the tune a slightly canned, somewhat recessed sound. The bass sounded full and grooving, lending a satisfying kick to the self-titled debut from 1980s pop/rockers The Bears, although the low end wasn’t as precise as with the GoVibe MBA. Overall, while I wouldn’t call the sound super-hi-fi, I would call it good — same as with some of the tube amps I’ve owned.
Measured frequency response of the Fireye Mini into a 32-ohm load at 1 mW is pretty good and actually a little better than specified. There’s just -0.05 dB of treble rolloff at 20 Hz. However, there’s significant bass rolloff: It reaches -3 dB at 17 Hz. Maximum output at 1 kHz into a 32-ohm load falls in the middle of the pack: 260.2 mW at 1% THD+N. But it had problems with the 250-ohm load, falling behind the other amps’ output. Maximum gain at 1 kHz is +6.2 dB. A-weighted signal-to-noise ratio at 1 kHz is -98.4 dB. Output impedance at 1 kHz is 10.7 ohms.
Although the Fireye Mini isn’t perfect sonically, it is a substantial improvement over the straight sound from my cell phone, and it has what I think is the friendliest form factor of any mini headphone amp. Because of that, I found myself using it often when my formal testing was over.
Are Apple devices known to have decent quality amps already? Because I just got a Fiio E6 and I'm having a really difficult time finding much difference with and without the amp on my iPhone 4, iPod Nano or MBP. I've listened to a wide range of music on all three devices mostly with a pair of $100 Sony circumaural phones (MDR-V6). I've also tried using some cheap ($20) IEMs and don't see much difference with the amp present or absent on any of these devices. For $30, I don't regret the purchase since I can use the E6 while travelling and keep the volume output on my audio devices low to conserve the battery.
Yes, Apple portable products have a good reputation for audio quality. I've measured a couple of them and of course listened to a lot of them, and the qualtiy is excellent for portable products.
Also, I found that of the three amps tested, the E6 sounded the least different from my Droid alone, as long as I didn't use any of the EQ modes. The differences are easist to hear on treble-heavy recordings, such as high-quality recordings of acoustic guitars.
@brentbutterworth I have a pair of quite good IEMs and I just purchased the Fiio E6, as well as the Fiio L3 LOD. I am planning on using this with my Ipod and Ipad when I am on the go as I travel quite a bit. Would there be a better system to get a HIFI on the go, without spending hundreds on something like the NuForce iDo?
@monney - We have some ideas for getting high-resolution output from your iOS devices, at a variety of price points, in this piece: http://www.soundandvisionmag.com/article/ipad-high-rez-digital-transport...
Those solutions involve a couple of additional external devices, so I'm not sure you can beat an LOD cable and external mini headphone amp for pure portability, but there are many options nowadays.
Please check it out and let us know if anything looks like a possibility for you.