Headphone Amp/DAC Reviews

Firestone Audio Fireye Mini ($39)

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.