FiiO E9 Desktop Headphone Amplifier and Dock for E7 USB DAC

I first purchased this amplifier to go along with my E7 portable Amp/DAC (also by FiiO - it 'docks' into this amp to provide a DAC). I'd just purchased a pair of Sennheiser HD 650s, and they benefit greatly from amplification. The E7/E9 combo works quite well for mid-level headphones like the Sennheiser HD 650, but to really get the most out of this amplifier, you need to pair it with a better DAC. FiiO is coming out with the E11 soon, and although I'm not sure if it pairs with this amp, it would be foolish of FiiO not to build it into the E11.Headphones in the 'Mid-Fi' range frequently REQUIRE amplification to sound their best, and the HD 650 is no different. Unamped out out of my iMac, they sound alright, but the sound is thin, and the bass lacks presence - the mid-range is also recessed. With the E7/E9 combo, the sound fills out a great deal more - but the mids are still recessed. I had thought it was a weakness of the HD 650s or of the amplifier itself ($130 for an amplifier is an AMAZING deal - so I'd expected some trade-offs). In preparation for an upgraded amp and better headphones, I purchased the HRT Music Streamer II+ (also from Amazon). I paired it with the E9 using a relatively cheap RCA to Mini-jack cable.Wow! The HRT MSII+ really corrects any weaknesses in the sound from the E7/E9 combo and shows me that the thin mids were more a weakness of the E7 DAC and not the E9 amplifier itself. There is still some sibilance at the upper ranges, but that could be due to any number of weaknesses in the chain (low bitrate mp3s exhibit it the most, poor production makes it worse - a lot of modern pop-music is mastered very 'bright' or treble-happy in order to overcome the limits of bad stereo products). Keep in mind that the HRT MS II+ is a $350 product - so it should be no surprise it beats the lowly $99 E7.I wholeheartedly recommend this amp! It's a steal, and it can grow with the rest of your chain until you're ready to try tube amps, Solid-State/Tube hybrids, or just flat out need more power (for some demanding dynamic headphones or 'planar magnetic' headphones). For the price, it's a must-buy.

I purchased this in mid-October 2011 and came home today to find that the 3.5mm headphone jack is no longer producing sound. The phono jack doesn't sound great so I now have a paperweight sitting on my desk.I opened it up to try and fix it (I figured maybe one of the solder joints broke or something) and found I can't slide the circuit board out because of the dock on the top that I don't use. I could probably force the little plastic insert out and remove the screws I suspect are there but I will likely purchase a better (more expensive?) headphone amp instead.Performed well when it worked...I did not abuse the device so I'm rather disappointed it lasted less than 6 months.

I'm happy with the E9. (Not anymore. See edit at bottom)My source is my iMac playing lossless and 320mbps AAC files, sent out through USB to the E9 with the E7 docked, acting as the DAC.I initially just wanted a place to put my E7 when I come home from work at night. The E9 is a convenient charging cradle for the E7 and the 1/4 inch jack is a bonus, as my home headphones (Sennheiser HD558's) have a 1/4" jack. But I didn't think my Sennheiser's actually needed more headroom than the E7 by itself already provides.And I can't really tell that the sound from these headphones is improved by addding in the E9... I *think* the bass may be a little punchier but it's subtle. The sound from the combo in general is fantastic.Regardless, the sound is in no way diminished from adding the E9 to the E7 already in use, it may be better, but what is definitely better is the convenience of having a permanent headphone "station" on my desk, one that also charges my E7. And the analog volume knob on the E9 is also very helpful. The construction is solid and reassuing with one caveat...The 3.5 mm socket is as flaky as you've heard. Jiggle the cord a little and the sound gets staticky or cuts out. You should be using the well-made 1/4" anyway, with an adaptor if necessary. Fiio put a resistor on the 3.5 mm socket which raises its impedance to unacceptable levels (30 ohms, I hear), damaging fidelity. Even the 1/4" at 10 ohms is probably too high, though with my 50 ohm Sennheisers I can't tell... they sound great.) So when buying this, just assume you are buying an amp with only one 1/4" jack and treat the 3.5 mm jack as if it doesn't even exist.If you can get past this defect, and you should be able to, given the great price/performance ratio, go for it.EDIT: after owning this for a few weeks, the E7 no longer docks correctly with the E9. The E7 will still charge in the cradle, but the USB can't get a lock unless you jiggle the E7 around in its cradle for awhile. Essentially, the cradle dock is cheap crap, poorly designed. I guess that's what I get for trying to cut corners and be miserly. Now I have to buy a real headphoine amp and although I could send this back and get a replacement piece of crap, it's still going to be crap.I can't recommend this product unless you like to take your chances with poorly made toys.