[nudd]

  I tried to charge AK120II using USB port on M8 LX while Centrance connected to the power supply with no success. To different USB type B - micro USB wires with the same result. But I noticed that M8 is charging by my Sony Xperia Z3 when connected. Is it normal? I wrote that M8 LX must charge through USB.

 
Hi sskom, can I ask if your Z3 can work with the M8 via USB OTG? If so what version of the Z3 firmware/android are you using?
 
For some reason my m8 doesn't recognise or link to my Z3 anymore (even though it used it), but it works with the computer USB port -> M8.
 
Thanks!

 

[ButtUglyJeff]

Rudi confirmed the ZX1 works, but battery life is awful.  I'm hoping the ZX2 shows great improvement in that regard...

 

[sluker]

No idea about the zx1, i think it is an android device so it would be different then the A10.
The battery life for the A10 is also atrocious compared to the A10 stand alone. I actually think the M8 draws power from the A10 and that is why it sucks the battery. 
Anyone know of a way to stop this from happening?

 

[sladewilson411]

  No idea about the zx1, i think it is an android device so it would be different then the A10.
The battery life for the A10 is also atrocious compared to the A10 stand alone. I actually think the M8 draws power from the A10 and that is why it sucks the battery. 
Anyone know of a way to stop this from happening?

I think when you use the A with the usb B, there is no way you can prevent that. Mine is the idevices version and when i use it with an ipod, the battery life performs normally

 

[sskom]

if your Z3 can work with the M8 via USB OTG? If so what version of the Z3 firmware/android are you using?

Yes. It works. M8 LX, Android 4.4.4, Build 23.0.1.F.0.96.

 

[the-kraken]

The stated power output for the m8 is 1.5w... I assume that's running balanced, and you'd get half that single ended.

Can anyone confirm?

 

[headwhacker]

Also not stated at what load the 1.5W is derived. But I'm guessing its below 50 Ohms. 

 

[the-kraken]

Agreed. the Innerfidelity measurements below
http://www.innerfidelity.com/images/CEntranceM8.pdf

 

[headwhacker]

Agreed. the Innerfidelity measurements below
http://www.innerfidelity.com/images/CEntranceM8.pdf

 
I guess that's the reason the spec sheet just mentioned a vague "1/1.5 watt" output power and nothing else. To put that into perspective/comparison, an O2/ODAC technically has more power driving high impedance cans over the hifi-m8 ( 7Vrms vs 5Vrms) and virtually similar driving current hungry/low impedance cans.  

 

[ButtUglyJeff]

The stated power output for the m8 is 1.5w... I assume that's running balanced, and you'd get half that single ended.

Can anyone confirm?

 
Mike chimed in, quite a while back, that this device is impedance balanced only.  That means the single ended output has the same power as balanced.  (you might want to dig back for verification)  The HiFi-M8 is my go to amp, when I don't have a balanced connection for a headphone, like my MDR-Z7, for that exact reason...

 

[goldgears55]

   
I guess that's the reason the spec sheet just mentioned a vague "1/1.5 watt" output power and nothing else. To put that into perspective/comparison, an O2/ODAC technically has more power driving high impedance cans over the hifi-m8 ( 7Vrms vs 5Vrms) and virtually similar driving current hungry/low impedance cans.  

My T1 is number 20124. I've done audition between O2/ODAC VS M8. To my ear, the M8 provide more power than O2/ODAC at the same volume position.

 

[headwhacker]

My T1 is number 20124. I've done audition between O2/ODAC VS M8. To my ear, the M8 provide more power than O2/ODAC at the same volume position.

Which gain is your O2 set? My O2/ODAC has 1x/3x gain.

I measured the output of both. O2 at 1x gain is equivalent to M8 on Mid gain which is around 2Vrms. O2 at 3.5x can put out 7Vrms which is way louder that M8.

When listening with my T1 I can't put the volume knob at max on O2 on high gain. But M8 just gets loud enough at high gain but not as loud as O2

 

[goldgears55]

Which gain is your O2 set? My O2/ODAC has 1x/3x gain.

I measured the output of both. O2 at 1x gain is equivalent to M8 on Mid gain which is around 2Vrms. O2 at 3.5x can put out 7Vrms which is way louder that M8.

When listening with my T1 I can't put the volume knob at max on O2 on high gain. But M8 just gets loud enough at high gain but not as loud as O2

Sorry, I forgot to ask the guy in the shop what's O2/ODAC(demo) gain during my audition. Anyway, to my ear M8 is more fun listening than O2.

 

[headwhacker]

  Sorry, I forgot to ask the guy in the shop what's O2/ODAC(demo) gain during my audition. Anyway, to my ear M8 is more fun listening than O2.

 
 
At matching volume level I found both O2/ODAC and M8 sounded similar on a blind test listening with T1. But with sensitive iems, M8 sounded a bit grainier background. Most likely because it has a higher noise floor than O2.

 

[headwhacker]

   
Mike chimed in, quite a while back, that this device is impedance balanced only.  That means the single ended output has the same power as balanced.  (you might want to dig back for verification)  The HiFi-M8 is my go to amp, when I don't have a balanced connection for a headphone, like my MDR-Z7, for that exact reason...

 
Still can't figure out the 1/1.5 Watt power output in the M8 spec is coming from.
 
EDIT: Or perhaps that is the power M8 consumes overall when driving cans at maximum capacity.