I recently purchased the FiiO E7 digital-to-analog converter (DAC) and FiiO E9 Desktop Headphone Amplifier after hearing and reading good things about the combo. Both products can be used separately on their own, but the manufacturer thought to design it so that the E7 can be docked into the E9 (illustrated at left) to create an even more-powerful product. The E7 also has an amplifier built-in, albeit not as powerful as the amplification the E9 is capable of. Also, the E7 features two 3.5mm headphone jacks, while the E9 enables RCA line out and a larger 1/4″ headphone jack in addition to the 3.5mm.
The E7 is designed to be portable, and is powered by a battery said to get 80+ hours on a full charge to let you listen on the road. It comes with a high quality line-in cable, and there are a variety of cables for it available separately, such as the L3 iPod “dock” cable that lets you send music out through an iPod/iPhone 30-pin cable instead of the headphone jack. It also comes out of the box with a protective screen, silicone casing, a padded carrying pouch, and a black silicone band to hold your iPod or other source of music against the DAC itself. Perhaps one of the nicest features is that it has two 3.5mm headphone jacks, making it easy to let someone else listen in. Build itself feels solid with the brushed aluminum casing, and overall it’s lighter than I expected it to be. While parked on your desktop, it’s powered by (and charges with) the included USB cable.
The E9 features a more powerful amplifier and is powered by an external AC power cord. Like it was mentioned before, it gives you a few more options like RCA out for external speakers. While it does have a USB-in, it should be noted that it only accepts USB audio when paired with the E7 as a DAC. Without the E7, you would have to use the computer’s built-in DAC and headphone port connected to the E9’s line-in.
Test: For testing purposes, I used Audio Technica ATH-AD700 (tunelab review) and ATH-M50 headphones. Both of these headphones deliver extremely accurate sound, particularly the M50s. The music I listened to for the review was a mix of modern rock bands whose music I know very well and some classical music that let me hear a more diverse range of sounds. Music was produced from CD or lossless .wav files using a late-2010 iMac, a 6th generation iPod Nano, and an HP Mini Netbook.
Result: Surprising to me (based on other reviews I’d read online), the E7/E9 combo produced no discernable difference in quality when compared to listening through the iMac’s headphone jack. As much as I tried, I couldn’t hear a difference in anything I listened to. None at all. Compared to the iPod’s headphone port, there was a slight improvement overall, and it was a bit of a bigger improvement with higher-pitched tones, as well as transitions from noise to quiet when there was abrupt changes in the song. I was using the FiiO L3 iPod dock cable to get line-out into the E7/E9. With the HP Netbook there was a pretty drastic difference—so much so that it was pretty much night and day.
Conclusion: Unfortunately, the bottomline when considering whether to buy the E7/E9 combo simply boils down to: “it depends.” The price is fantastic, and you can get both for just over $200 on Amazon.com. The best thing to do would be to listen to something you know is of the utmost quality and listen to see if you hear any distortion, or a “hiss” when there’s supposed to be quiet. If there is, this combo will probably fix that. With the Netbook, it’s pretty obvious to me that they skimped on the internal soundcard/DAC, and there’s little noise isolation. If I start a processor-intensive application, I can literally hear it through the headphones. Compared to the iPod and iMac though, the lack of a difference I think is more of a testament to the quality of the existing hardware. For instance, newer iPods all have Wolfson DACs internally, which is the same brand that powers the E7. I’m not sure what is in the iMac, but it’s obviously also a superior DAC. Also note that both of the headphones I was using were under 40 ohms, which don’t require an amp. (Ohms is the measurement of electrical impedance, which in the simplest terms means that the higher the number of ohms, the more power it takes to “push” the sound through them.) However, even a set of headphones with higher impedance doesn’t necessarily mean the sound quality will improve—it just means they need more amplification to function.
Another interesting thing I noticed is that when I compared the E7 solo to the E7/E9 combo, I found no difference there either, even with the Netbook. Again though, my headphones don’t need the more powerful amplification, which is the only real difference made when you add the E9 to the mix. The only reason I could see to keep the E9 is if I were powering external speakers/monitors both for the higher power, if I got a set of headphones that had really high impedance (because the E7 does have an amp of its own as well), or for the RCA line-out that the E7 doesn’t have on its own. For now, I’m returning the E9 and keeping the E7.