Generally, yes. You will also have to consider the sensitivity of the 'phone. Below 100dB/1mW is slightly more difficult to drive, beyond 110d/1mW is considered very easy to drive. Some headphones, though have spec that don't seems to be hard to drive, still require a lot of current reserve to perform well. For example, AKG K701.

On spec, both should be relatively easy to drive. However, just because it is easy to drive doesn't means it won't improve upon amping. As I said before, some headphone benefit from big current reserve, and you can't tell that from spec. You will have to try it out to find out. Some amp also have coloration that might be favored by the user, like the bass boost in E3 and E5.

You can use it with M3300, but since M330 already has its own power amp, all E5 will do is making it slightly louder.

I did, and still own it. With OPA2134, this little cmoy actually sounds really good.

Like I said before (Post #82), cmoy is considered a step up from E5.

Line Out Dock - a cable that connects to the player's dock connector that draws out the line-out signal. Usually has an 3.5mm mini plug on the other end so user can plug into an portable amp.

Here is how things work in DAP:

Music data -> CPU -> DAC -> AMP -> headphone.

DAC - Digital-to-Analog Converter, turns digital data to analog sound.

AMP - Amplifier, amplify the signal (music) from DAC to different set of gain (kind of like volume control).

In portable device, due to size restriction, the amp section is usually kept very simple and just enough to drive normal, easy to drive headphone. Some time, cheap SMD components (tiny resistor, capacitor, lousy chips) are used to cut cost and space - these result in a headphone signal that are sub-par. In order to extract as much sound quality as possible from the portable device, we use the line-out signal. Line-out means the signal is directly from the DAC, un-amplified (so it avoids all the sub-par components in the amp section). We connect the line-out to an external amp (which replace the function of the internal amp section), which hopefully will be a lot better than the internal amp and thus provide better SQ and more power to drive difficult-to-drive headphones.

Of course, the assumption is the internal amp is not going to be as good as (or as powerful as) the external amp you are going to use, or else the improvement will be really minimum (or none).

It is not 'ideal', but you can still get good result from amping headphone-out as long as the headphone-out is very good in SQ and 'clean' (low noise).

Depends on the output of the USB adapter / port, but usually it is less tha 3 hrs... and yes, till the right light goes off.

T4 is still in the market. You can think of it as the refined E5 - better on all count but a lot more expensive.

You need to tell us what kind of interference we are talking about first.

E3 is glued tight. the only way to open it is to crack it.

E7 will be amp+DAC that can be used both portably or on desktop. E1 will be be a portable amp that has a unique design.

I actually have the early spec here for feedback purposes, but I have agreed not to share any detail. All I can say is, if you like E5, then you will definitely like the upcoming amps. Of course, they will also be very affordable.

I am not sure when is the release date, but I will keep you guys informed.

To minimize hiss, you need to keep the source volume high (assuming you are using headphone-out) and E5's volume low. This also helps to keep the dynamic range high (SQ is better this way).

E7 is not out yet. In fact, no release date yet.

This has been posted on Head-Fi for a few days now, but I guess I post it here as well.
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I just received an email from our friends over at FiiO (Thanks, James) with more information regarding their new amps, and this time I get the go-ahead to share them with all of you.

Here is the rendering of the new FiiO E1, an in-line amp for iPod. No production shot yet since FiiO has yet to make the final production model. It utilizes the power supply and line-out signal from iPod dock connection and incorporate an digital volume control as a remote. You can think of it as the union of E5 + LOD. The ETA is around end of August / early September. Not sure about the price yet.



Here are some pre-production shot of FiiO E7, FiiO upcoming USB DAC + AMP, note that this is not the final look (but it probably won't be too far off). Battery life is expected to be >100hrs, The 5 sides of the housing are CNC'ed aluminum (with harden acrylic on the last). ETA is estimated at December (likely around X'mas like the E5). There will be a dock planned for later release, which will enable remote control function and two line-out (one variable and one not) in case you want to connect it to speaker or use the DAC function only. E7 will have a special dock connector for docking and there is also plan for further accessories development, which will allow connection to desktop amp, mini Hi-Fi set, speaker and such. E7's price is estimated to be lower than US$100.









So, any thing else you want to know?

No, not much update lately.

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Added on September 23, 2009, 2:44 pmSome update:

I'll be getting a fully functional final production E1 either by Friday or early next week. So here are some of the functions: Play/Pause, Next/Previous, Volume Up/Down, Fast Forward/Backward, Mute.

This post has been edited by ClieOS: Sep 23 2009, 02:44 PM

Some update:

A black edition E1 will be released on the next batch.

Here is the new rendering of E7: Along with some inner hardware changes and the face lift, the new casing is also slimmer than the previous prototype showed before.


This is the proposed E9 prototype. Basically it is desktop amp with an iPod / FiiO dock integration. You can either 1) dock you iPod / iPhone on E9 and feed it the line-out, 2) dock the E7 and give E9 the USB DAC function (E7 will feed line level signal from E7 DAC directly back to E9 amp section). You can think of E7 as E9's DAC module. or 3) Feed E9 a line-in analog signal, just like most other desktop amp. E9 will also feature a better, newly design amp section that is different from E7. E9 is scheduled for early 2010.

My review is here: http://forum.lowyat.net/index.php?showtopic=1182124