[badbat]

Every thing seems to be in fine order other then the volume. It does get louder with the gain switch on by maybe 15% or so. cross feed works(I'll never use this feature) and the bass switch adds a little more punch. I don't hear static at all. A hiss with high gain. the amp was like this out of the box. I've only charged it once and I checked the authenticity code

 

[utmelidze]

they have improved usb charging mode a lot since last year on E12
E12 from 2012 Q4 had audible hiss with usb charging and hearing
it had weaker battery
 
new E12 lasts extremely long...in my case even 20 Hours and usb charging is not audible anymore

 

[Hollus]

Hello, had a couple questions.
 
Is the charging LED supposed to turn off automatically once it's done?  I was expecting it to do so, but I've had mine plugged in for ~24 hours (turned off) and am still getting a solid LED.
 
Secondly, would using http://tinyurl.com/lmvjc7c (usb wall plug) pull a 2A/h fast charge off of an outlet?

 

[BenF]

  Hello, had a couple questions.
 
Is the charging LED supposed to turn off automatically once it's done?  I was expecting it to do so, but I've had mine plugged in for ~24 hours (turned off) and am still getting a solid LED.
 
Secondly, would using http://tinyurl.com/lmvjc7c (usb wall plug) pull a 2A/h fast charge off of an outlet?

I think the LED blinks during the charge, stays on once it's finished.
Wall charger will speed things up.

 

[benbenkr]

  they have improved usb charging mode a lot since last year on E12
E12 from 2012 Q4 had audible hiss with usb charging and hearing
it had weaker battery
 
new E12 lasts extremely long...in my case even 20 Hours and usb charging is not audible anymore

 
By "new" you mean the late 2013 repackaged E12 right (the one with the new red/black box)?

 

[utmelidze]

yes. i mean red repacked E12
i can compare and confirm:
 
Battery is lot better
usb charging is completely silent now
 
bad news: bag is lot cheaper comparing to old one. it doesnt really looks well compared to E12 quality

 

[PocketSmiley]

The solution to USB charging noise:
 

 
Use a USB cable with a ferrite choke. (Doesn't work in my E12 with my PC; can't test with my laptop which is dead right now.) I charge my E12 with a separate USB wall charger and it's completely silent.
 
I hear noise in my Fiio E5 when it's both sourced and charging from the same laptop/PC. Using a ferrite choked charging cable effectively mutes MOST noise; there's still noise but it's tolerable and you can't hear them with music playing. Charging from the laptop but listening to my phone source doesn't have noise in the E5.
 
I just got a Fiio E12. I love it, especially its high input voltage handling. The E5 clips beyond 1.2Vrms, when my soundcard outputs 2Vrms at max volume. The E12 handles my soundcard output easily.
 
I use a 2A500mA USB charger wall adapter to charge the Fiio E12, but the E12 gets too hot when charging. I want to keep the E12 powered as I use it as a desktop amp. I haven't tried charging it from the PC, but the USB ports output the same 500mA as my wall charger. Any experience with this? Is there a way to keep the E12 cool while powered? Or is the E12 going to be okay at such high temperatures?

 

[benbenkr]

By hot, how hot is it? Burning hot as in too hot to touch? Warm?
The case is built from aluminium, it's good heat dissapation. 

 

[PocketSmiley]

  By hot, how hot is it? Burning hot as in too hot to touch? Warm?
The case is built from aluminium, it's good heat dissapation. 

 
It's normal laptop battery hot. It's only alarming because when not charging, the device stays cool. But when I left it plugged in for 24 hours (so supposedly fully charged) and felt that it was still hot, I was worried about leaving it that way. I know electronic components are built to withstand heat. But not always.

 

[Hawaiibadboy]

  Thanks for the fast reply. I should of stated that the source volume is at max. Everything sounds great. I thought it was going to be louder. I think the volume nob might not be working right

 
How about you turn the source (for an example: Cowon at 32volume)<<<<<and never ever touch it again (Turning a source volume to max seems odd since you can turn it to 3/4 and lean on the amp...the thing you bought to amp the signal....no?)
 
Now switch your gain to on and use the amp as your default volume knob forever.

 

[benbenkr]

   
It's normal laptop battery hot. It's only alarming because when not charging, the device stays cool. But when I left it plugged in for 24 hours (so supposedly fully charged) and felt that it was still hot, I was worried about leaving it that way. I know electronic components are built to withstand heat. But not always.

 
FiiO states that their portable amps run on USB power and almost entirely cuts off its battery when plugged in. So yeah, it makes sense that it remains hot. Same thing for every other amp that uses USB or even an external power supply.
 
If your E12 is turned off and it isn't charging but plugged in, if it's still hot then there's a cause for concern. Is this a problem you are facing?

 

[PocketSmiley]

   
FiiO states that their portable amps run on USB power and almost entirely cuts off its battery when plugged in. So yeah, it makes sense that it remains hot. Same thing for every other amp that uses USB or even an external power supply.
 
If your E12 is turned off and it isn't charging but plugged in, if it's still hot then there's a cause for concern. Is this a problem you are facing?

 
Ah, thank you! I don't remember it being fully charged, and if it ever was, I don't remember if it's turned off. All I know is that for the entire day today, I kept it plugged in and turned on, but the charging light never stopped blinking. Is it supposed to stop charging even while it's turned on?
 
I'm charging it right now turned off. I'll get back when it's fully charged. If it doesn't get fully charged maybe I got a defective unit.

 

[benbenkr]

   
Ah, thank you! I don't remember it being fully charged, and if it ever was, I don't remember if it's turned off. All I know is that for the entire day today, I kept it plugged in and turned on, but the charging light never stopped blinking. Is it supposed to stop charging even while it's turned on?
 
I'm charging it right now turned off. I'll get back when it's fully charged. If it doesn't get fully charged maybe I got a defective unit.

 
The E12 charges when it is turned on too, but its rate of charging is slower than when it is turned off. This is because like I said earlier, the amp uses the power from the USB instead of the battery. The battery would continue to charge, but at a slower rate. Another reason why people hear hiss on the earlier models.
 
It should charge fully after 4-5 hours. Mine finishes charging at around 4 hours most of the time.

 

[PocketSmiley]

   
FiiO states that their portable amps run on USB power and almost entirely cuts off its battery when plugged in. So yeah, it makes sense that it remains hot. Same thing for every other amp that uses USB or even an external power supply.
 
If your E12 is turned off and it isn't charging but plugged in, if it's still hot then there's a cause for concern. Is this a problem you are facing?

 
 
I solved the heating problem! My E12 also charges fully, and the charge light shows it! My E12 is perfect!
 
I used a 2.4A USB wall charger to charge it to full, with the charge light blinking rapidly. At first I was scared that my E12 charge light is defective and that it can't detect if the device is fully charged. But then it finished charging. Now I'm using it plugged in, but it still shows it's fully charged so it's all perfect!
 
Weird things:
 
When I was charging using the 2.4A charger with the E12 turned off, the E12 was cool all throughout! And when I turned it on again, still plugged to the charger, the charging light stays full, and after using it for an hour it is still cool!
 
Previously, I was using a 500mA USB wall charger. With the E12 battery drained, I tried to use it while charging. The charge light kept blinking for 24 hours with the E12 turned on. Most importantly, the E12 was running hot.
 
If you want to use your E12 while charging, it is best to charge it fully first so it doesn't get hot.
 
EDIT: Just after typing this, the charge light started to blink again. It's blinking slowly, so it means it's charging slowly even though it's plugged to a 2.4A charger (5V, 12 watts). I'm pretty sure the E12 doesn't eat 12 watts of power when driving 16-ohm headphones. I'll check again if it gets hot again. So far it's still cool.

 

[desertpeaks]

Mine was hot only the first charge using my phones 1.2A charger. Since then it's cool.