[KT66]

The volume knob has more steps, nicer case
 
Second oscillator, gapless playback, 2 second startup, 24 bit playback, including ALAC and DSD, improved wheel... ESS9018x2, and amp with OPA627x2, OPA2107x2.
 
http://www.head-direct.com/Products/?act=detail&id=265

 

[laimk]

  I have had conflicting answers,but I believe the exchange scheme is happening in China first, then ROW
however it's not an exchange per se, your 901 is reshelled into 901s case, it will not be a 901s.

i am from Singapore, and i have sent mine for reshelling. i think it should be coming back soon to me within this week. From what i understand, after this batch, Hifiman will not entertain anymore reshell requests. I hope this information is incorrect.
i will update if time allows for me to do so.
 
according to Dr.Fang, the reshell include some tweaking that will make the "old 901" to sound like the "901s". my guess is the output stage after the amp board for which the balanced switch is discarded and replaced with a discrete balanced or non balanced output socket. which means they have to change this board physically.
 
the main difference is the SOC for which i heard is on a standby mode and startup is within seconds only. The "901" after reshelling, will not have this mode as the SOC is still using the old board untouched.

 

[KT66]

I'm a bit surprised no one from HIFIMAN or HeadDirect has informed us here about the scheme, and I see no mention of it on their web site

 

[Trogdor]

I'm a bit surprised no one from HIFIMAN or HeadDirect has informed us here about the scheme, and I see no mention of it on their web site

I've email Head-Direct back in April and they said they didn't have any specific details as of yet. I've just emailed again. Hopefully, they have more details now.

 

[laimk]

I'm a bit surprised no one from HIFIMAN or HeadDirect has informed us here about the scheme, and I see no mention of it on their web site

 
 

I've email Head-Direct back in April and they said they didn't have any specific details as of yet. I've just emailed again. Hopefully, they have more details now.

Yes, i do not see any news on it at all. I just send my 901 back to China Guangzhou and let my dealer handle it. He told me 10 sets from his customers has been sent back to Hifiman and we are still waiting since March. He also told me today again, Hifiman is not taking anymore 901 for reworks (of course he is referring to China only.) . Let's see what Hifiman will do to customers in the USA.

 

[KT66]

And Europe, in the UK the HifiMan dealers are pretty useless.

 

[laimk]

901S is back. Retrofitted but no time to play with it yet. Just to send out the difference in switch. When I have the time will update more.

 

[Edwood]

Please help me...
I use sandisk 128gb micro sd card

After file scanning, it works great.
However,.... when i reboot hm901, the file lists are disappeared.
Folders are remained..

So i should to scan files every time for listening music..

Is it only my problem ?? T.T

I have this exact same problem with the Sandisk Extreme Plus 256GB card.
http://www.amazon.com/gp/product/B00P870LOK?psc=1&redirect=true&ref_=oh_aui_detailpage_o03_s00
 
I tried two different ones and they both had the same problem.  It's a compatibility issue I'm sure, as the same files don't cause the problems with a smaller 128GB Extreme Pro card.  Perhaps the 256GB Extreme Pro is fundamentally different than the Extreme Plus line?

 

[laimk]

After running-in my new cables for UM IEM 12 drivers, i made some comparisons on my 901S (re-cased)
 
1. the modded 901S has the wordings "Upgraded from HM901" on the display glass.
2. the high low switch is retained where the new 901S does not have the high low switch.
3. tested with 1. RE600, 2: UM 12 drivers, 3. Audeze LCD 3
4. compared with the 901S, AK 240 Gold and Old 901
 
1. Sound: 901S vs 901
First impression is different soundeing 
All headsets tested.
 
a. RE600, 901S is brighter in the 6k-8Khz. Bass has lesser punch. Maybe because of the brighter sound, the detailing is better.
the bad side for my personal preference, i feel tired after listening to 901S after an hour.
b. Audeze LCD3 The ambience is missing, the 3 dimensional sound from original sound is missing. Listening to Overture 1812, the bass, drums and Canons lacks punch. Detailing is good.
c. UM12, clarity, bass is strong, smooth in both 901 - like the clarity. After listening to female vocals, Cai Qin, Celine Dion and other vocals, they are sweet...male vocals sounded weak.
 
Overall, i prefer the older sounding 901. 
 
versus AK240:
1. Ak240 has this signature sound of right up in your face with nice imagining. seems like the new 901S is missing that although the detailing is better than the old 901. i am not sure why.
2. 901S amp: Power to drive the LCD 3 is adequate compared to the AK240. Both in Balanced mode.
3. Imaging, AK sounded better marginally.
 
 
i have to say, the 901S sounded very nice in the RE600. The Audeze and UM on 901 is better than on the 901S.
 
Overall feel of the 901S design is still crappy. you need to remove two screws before you can change the battery and the amplifier card.
the look is like some form of poorly design aluminium sheet metal.
Although more modern look now, it is still very retro and feel huge in the palm.
 
More details if i have the time to listen more music before posting.
 
 
 
 
 
 

 

 

 

 

 

 

[KT66]

First meaningful review of 901s , thanks

 

[system11]

Well I got my 901 (well, a replacement) and the new firmware is nicer, as is having left/right which are balanced again.  Scroll wheel now causes noise over the audio which is offputting, is that common on units?  I've had terrible luck generally so far with these, the one sent back was my third.  I almost wish they didn't sound so good, but .. they do.  They really do sound better than anything else IMO especially paired with my Denons.
 
Special thanks to DHL who decided they needed to check the package and cut through it with a retractable blade knife, through the packaging, through the ESD bag and ultimately through the paint on the battery cover.  I'm talking to those idiots now....  At least it wasn't the front I suppose.

 

[punit]

901s trade in offer for 901 owners for $ 499.
 
http://www.head-direct.com/Products/?act=detail&id=275
 
Think I will go for this.

 

[Trogdor]

901s trade in offer for 901 owners for $ 499.

http://www.head-direct.com/Products/?act=detail&id=275

Think I will go for this.

I think this is a direct replacement too.

 

[Trogdor]

Well I got my 901 (well, a replacement) and the new firmware is nicer, as is having left/right which are balanced again.  Scroll wheel now causes noise over the audio which is offputting, is that common on units?

Yes. It's a real pot so they will always make a little noise (it's not just the 901).

 

[system11]

Yes. It's a real pot so they will always make a little noise (it's not just the 901).

 
I mean the navigation dial rather than the volume control
 
I contacted Hifiman about the problem with DHL damaging my replacement in transit.  In short, they don't seem to care and instead tried to sell me an upgrade.
 
I'm not very happy, that's terrible customer service.  "Oh I'm sorry, we can't be bothered to claim the cost back from DHL and post you a battery cover, why not just put up with it or go for our 901S upgrade?"