[frankrondaniel]

Did they tell you what's the root cause of the HO problem?

 
Unfortunately no specifics other than they confirmed that it didn't work.

 

[LarsHP]

If my experience is of any help, I noticed the L/R channel reversal ONCE. Never since. So not a big deal.

Found this very, very long review of HM-901, AK120 and MA9:

http://www.head-fi.org/products/hifiman-hm-901/reviews/10342#comments-title

Sorry if this is "old news".

 

[CosmicHolyGhost]

Channel reverse is an intermittent firmware bug and will be fixed hopefully in next firmware..i read this from erji

 

[CosmicHolyGhost]

Can anyone tell me why DAP uses dock to get line out will consume more battery than normal listening with PO? Hm901, zx-1, ipod
But DAP will dedicated line out jack saves battery from using line out...

 

[ClieOS]

Can anyone tell me why DAP uses dock to get line out will consume more battery than normal listening with PO? Hm901, zx-1, ipod
But DAP will dedicated line out jack saves battery from using line out...

 
That doesn't make any sense. The only thing I can think about is that some DAP has both LO and PO activated all the time, even though you are not using PO. Other disable PO when the LO is plugged in (which is easier to implement when you have a dedicated LO jack) and therefore able to save more battery. Actually some who use HM901's LO exclusively have remove the amp module all together to improve the battery life.
 
I reckon this has nothing to do with LO vs. PO, but more to do with how different implementation works.

 

[CosmicHolyGhost]

   
That doesn't make any sense. The only thing I can think about is that some DAP has both LO and PO activated all the time, even though you are not using PO. Other disable PO when the LO is plugged in (which is easier to implement when you have a dedicated LO jack) and therefore able to save more battery. Actually some who use HM901's LO exclusively have remove the amp module all together to improve the battery life.
 
I reckon this has nothing to do with LO vs. PO, but more to do with how different implementation works.

thanks... I have read that for HM-901, ZX-1 and idevices, users have reported that using LOD actually has less battery life than normal listening.... so I guess it is the implementation. If I read correctly, we can still take out the amp card to save more battery which is a good thing for HM-901.. I use the HM-901 as line out source until I buy a new DAC next month

 

[pekingduck]

@jamato8 how to get balanced LO out of the 901? I remember someone say the upcoming dock will only have Unbalanced output?

 

[jamato8]

@jamato8 how to get balanced LO out of the 901? I remember someone say the upcoming dock will only have Unbalanced output?

Sorry, was thinking of the headphone out. My whole stereo home system is a balanced system that I built using some of the finest transformers from Audio Note Uk (two of the transformers alone can easily cost more than the AK240). I like balanced but I think single ended can be excellent also. So the balanced line out doesn't do it for me one way or the other. 

 

[CosmicHolyGhost]

but that line out of AK240 is not yet confirmed to be "line out".... and people will spend extra hundreds of dollars for mod to get the line out...then iriver will knock it saying it is not superior SQ... whole thing is a bit bizarre...

 

[jamato8]

  but that line out of AK240 is not yet confirmed to be "line out".... and people will spend extra hundreds of dollars for mod to get the line out...then iriver will knock it saying it is not superior SQ... whole thing is a bit bizarre...

Well they have to defend their design. Turning the volume to max via the dac, but after that it depends upon what iRiver is passing the signal through. For the 901, maybe a specialized card as a line out balanced with the volume on the 901 at max so you effectively not going through any resistors and just the wipers on the volume control. 

 

[pekingduck]

Just went to a local shop today to demo the Chord Hugo and AK240. Below is a little comparison to the 901.
 
Hugo: I mainly came for the Hugo but its damn battery ran out after 20 mins or so. The first impression I got was that the Hugo was very resolving, and open and bold sounding. It projected a larger sonic image than the 901 but at the same it could fill up that space with lots of details (instead of bump up the mids to thicken the sound). Bass on the Hugo was noticeably tighter but the very short decay made it sound a bit unnatural to me. Overall I would say the Hugo sounded very hi-fi but the 901 sounded more realistic (though technically less capable). I was going to pull the trigger but the bass issue bothered me a bit.
 
AK240: Detail retrieval was similar but soundstage not as wide as the 901 and not as dynamic. The 240 was very polite sounding, perhaps too polite to me. Vocals are ultra smooth with no grain. Ultimately it boils down to your music preference: for fast-paced or large-scale music with lots of instruments, the 901 is a clear winner. Although I didn't try, but for slow-paced music I can imagine some (especially jazz / female vocal lovers) may prefer the 240.

 

[flaco]

  Just went to a local shop today to demo the Chord Hugo and AK240. Below is a little comparison to the 901.
 
Hugo: I mainly came for the Hugo but its damn battery ran out after 20 mins or so. The first impression I got was that the Hugo was very resolving, and open and bold sounding. It projected a larger sonic image than the 901 but at the same it could fill up that space with lots of details (instead of bump up the mids to thicken the sound). Bass on the Hugo was noticeably tighter but the very short decay made it sound a bit unnatural to me. Overall I would say the Hugo sounded very hi-fi but the 901 sounded more realistic (though technically less capable). I was going to pull the trigger but the bass issue bothered me a bit.
 
AK240: Detail retrieval was similar but soundstage not as wide as the 901 and not as dynamic. The 240 was very polite sounding, perhaps too polite to me. Vocals are ultra smooth with no grain. Ultimately it boils down to your music preference: for fast-paced or large-scale music with lots of instruments, the 901 is a clear winner. Although I didn't try, but for slow-paced music I can imagine some (especially jazz / female vocal lovers) may prefer the 240.

Nice comparison! I am also interested in the Hugo since day one. Hope it can compete with the 901. Which headphones were you using ? Because of close to 1 ohm output impedance....

 

[pekingduck]

  Nice comparison! I am also interested in the Hugo since day one. Hope it can compete with the 901. Which headphones were you using ? Because of close to 1 ohm output impedance....

 
You mean 901 has 1 ohm impedance?
The output impedance of Hugo is a 0.075 ohms so it shouldn't be a problem at all.
 
I was using the JH Roxanne (15ohms). 

 

[jamato8]

1 ohm is nothing in the effect on the sound that I am aware of. There are some good amps out there with 3 ohms. It is when you start getting higher than that, that you run into a problem but I agree, the lower the better overall. 
 
With the Hugo that low on battery I doubt you would have heard the full potential and I doubt the Huge is fully burned in and often the bass is the last thing to really mature. I would want to hear the Hugo with a fully charged battery. Can't it be listened to while plugged in?  If the 901 satisfies musically, there is no reason something else will do better. In other words, maybe different, maybe larger but if it sounds like music, it becomes a preference rather than A being better than B. IMO. 
 
I didn't know the Roxanne was 15 ohms. That is low. 

 

[Makiah S]

So how exactly does the HM901 achieve line out? I saw some kind of Docking to 3.5mm connector being sold on Head Direct
 
I do NOT want to carry ANY kind of "docking" device with me to use the Line out, I can live with a docking Cable for line out use. That said how much improved is bettery life without the amp card and only using LO with the unit.
 
My hm801 is... kinda dead. It has no USB support and for $100 I get a warrenty and have my 801 replaced... BUT I'm worried  I'll wind up with a new HM801 that pops in between tracks... that is something my current unit has never done [it is apprently 2-3 years old] 
 
So that said, how does the hm901  achieve line out, and what is the  most stable and neutral sounding firmware. I like my hm801. never had to change the firm ware on it, and OMG line out on board... but I'm terrified to get a unit that pops inbetween tracks... I had an old DAP that did that it drove me nuts
 
I did contact Hifiman about any kind of protection from "popping"