Last year, Fiio introduced their first digital-to-analog converter called the E7, that was based on Wolfson’s high end WM8740 D/A chip. The E7 was priced aggressively at under $100, and it become a strong alternative for people looking for an entry level DAC for their headphone systems. This time, Fiio has released their first ever desktop headphone amplifier that is designed to be a natural upgrade path for owners of the E7 DAC.
Before the E9, there was no way to tap into the real capability of the E7′s WM8740, as the E7 didn’t come with an analog line level output. However, Fiio has thought about future expandability by installing an Ipod-style dock connector into the E7, from which a pure line out signal can be obtained from the E7′s DAC section. It comes naturally that the E9 comes equipped with a dock connector that matches the E7′s, making it the only product with the capability of accessing the line level analog signal out of the E7′s DAC section. This makes the E9 a strong product offering to existing E7 owners who now wishes to build a desktop system around their E7 DAC. And even more, with a total price of $200 for the E7 and the E9, Fiio has got a great product combination at a competitive price for headphone users shopping for a desktop DAC-Amp combo.
The E9 is designed to be a small box with multiple functions. When paired with the E7, it can do two things. Perform as a USB DAC-amplifier, or purely as a USB-DAC, where the amplification part can be done on a different amplifier through connecting to the E9′s analog line out port. Fiio has also installed an analog input port, so the E9 can be used purely as an amplifier, without the need of pairing with the E7. Without the presence of an input selector, the E9 automatically mutes the E7 DAC section when a connection is detected on the analog line input.
Fiio built the E9 around Texas Instrument’s well-known TPA6120 amplifier chip, and given a good circuit design and power supply, the E9 should be quite a potent desktop amplifier for the price. One thing that Fiio said regarding the E9 is that it’s not supposed to improve the sound output of the E7 DAC very much, as its primary function is to provide a stronger amplifier section. Now, I don’t know if Fiio is being overly modest, or if something has been lost in the translation of that statement, but I definitely can’t help but feel that the sound out of the E9′s headphone out is bigger and more open than if I had gone directly to the E7′s headphone out. After going A-B several times, I’ve convinced myself that the E9 indeed gives a more open sound and a more spacious soundstage. But the difference can be quite subtle on some recordings, and in this case open mic-ed live recordings shows the differences better.
Fiio cleverly installed a 33 Ohm resistor at the 1/8″ jack, in anticipation for headphones with higher sensitivity that would probably be terminated in 1/8″ jacks. This works well to give more range of volume control for IEM use, but it also works quite beautifully for music-sharing because you can listen to a full size headphone and an IEM simultaneously at both jacks, and not have a big discrepancy between the volume outputs. For instance, plugging in the Sennheiser HD558 and the q-Jays IEM simultaneously, the volume works out to be quite good in both outputs. Of course this will work better with some headphone/IEM combination and less so with others. Between the 1/8″ and the 1/4″ output jacks, there is a slight sound difference that’s probably caused by the 33 Ohms resistor. I feel that the 1/4″ jack, without the resistor, give a more open and clearer sound, and it’s the one I use the most. However, if you feel that there is too much treble presence on the recording, using the 1/8″ jack is prefferable as it sounds less bright and generally warmer.
Equipped with the high power TPA6120 chip, the E9 has tons of gain for the most demanding headphones, even in “lifting” the ultra low-sensitive Hifiman’s Orthodynamic HE-6. It’s quite obvious that the E9 is quite successful in achieving the one objective it was designed to do. Looking at the E7/E9 system as a whole, the sound quality is quite good for an entry level DAC/Amp device. The DAC section carries a slightly warm tone, and the amplifier section is quite neutral and enjoyable to listen to.
Using the E9 with the q-Jays dual balanced-armature IEM, the RK097 ALPS was fine enough that it didn’t show any channel imbalance at low volume. However, volume control was not as progressive as I would liked it to be, as there was a jump from no volume to medium loudness level. It’s not a big problem as I was still able to listen to the q-Jays at a reasonably medium low volume. I do think that the gain setting is set far too high, as I never saw the need for using the high gain setting (except when using the HE-6, but I doubt a lot of people will be using this headphone with the E9). It would be more user friendly if gain setting was a bit lower, so we can get better volume control for IEMs on the low gain, where big full size headphones can make use of the high gain setting.
The E7-E9 combo is not a perfect product, and there are small things that I wished they could’ve done differently. Perhaps my first complain is for the light-weight feeling of the volume knob. Lacking resistance from the RK097 potentiometer, I tend to over-turn the knob when changing volume levels. Of course, you’d also realize that turning the knob on the E9 doesn’t change the volume level display on the E7. A small thing, but it does get in the way of the user’s experience. Next, the lack of power switch integration requires the E7 to be turned on separately from the E9. Fiio has their own explanation for not having that feature on, and of course you can simply leave the E7 always turned continually since the E9 will supply charging power through the docks.
One function that the E9 missed is the ability to have the bass boost feature of the E7 to be passed on to the E9′s headphone out. Technical debates aside, I think a big percentage of people who enjoyed the E7 for its bass boost feature would be disappointed in this aspect. Lastly, for users who also take the E7 out for a portable set up would realize that the E7 doesn’t fit in the E9′s dock, when the rubber jacket is on. There’s another case that I believe could’ve been done better.
The sound from the E9 amplifier is generally neutral with little colorations. I enjoy the E9 more with the HD650 or the HD558, and less so with the more neutral Audio Technica M-50. The last TPA6120 based amp I used was Doobooloo’s portable balanced amp, and I thought it had a punchier upper bass and a fuller midrange section. The E9 can drive headphones to louder volumes, but I sort of missed the upper bass punch of the Doobooloo amp.
For a total budget price of around $200 (depending on different retailer pricing), the Fiio E7/E9 combination is quite a good value entry level product to have. Some competitors in the price range would include the Audinst HUD-MX1 and the Nuforce uDAC, but none of them have the headphone driving ability that I found on the E9 to have. I think Fiio has progressed a very long way from the days when they released their E3 amplifier. Congratulations, James!
Gears used for review:
Headphones: Hifiman HE-6, Sennheiser HD650, HD558, Audio Technica ATH M-50, Jays q-Jays
Source: Fiio E7
Amplifier: Fiio E9