[Nankai]

Thanks for KillerX's post. I have confirmed with him that it is a standard amplifier module damaging problem because his 901 line out is working fine. I do have a feeling it is a stupid problem that can be solved by burn in in factory, but we need to do more research other than burn in. I have called our manufacturing manager 5 min ago and we will check all of our stock standard card and make sure this problem will not happen again. We will check our AD8397 vendor about this problem as well and make sure it is not a chip problem. We are also working on QC procedures so that we can 100% get rid of defective amp cards before shipping. From now on we will buring in all amplfier modules for 48 hrs before shipping.
 
Because we can not ship standard card at this short period time, all customers who currently have pending 901 with standard card order will get IEM cards to replace standard card. 

 

[Trogdor]

Thanks for KillerX's post. I have confirmed with him that it is a standard amplifier module damaging problem because his 901 line out is working fine. I do have a feeling it is a stupid problem that can be solved by burn in in factory, but we need to do more research other than burn in. I have called our manufacturing manager 5 min ago and we will check all of our stock standard card and make sure this problem will not happen again. We will check our AD8397 vendor about this problem as well and make sure it is not a chip problem. We are also working on QC procedures so that we can 100% get rid of defective amp cards before shipping. From now on we will buring in all amplfier modules for 48 hrs before shipping.

Because we can not ship standard card at this short period time, all customers who have pending 901 currently with standard card order will get IEM cards to replace standard card. 

Fang, so if we are current owners of the standard card, we can swap them for the IEM ones? Is that right?

 

[Nankai]

Hi Trogdor,
 
We have sold several thousand HM901 players in the world (we release 901 early 2013 in Asia). I hope you could understand that we will fell to bankruptcy if we change several thousand standard cards only after one card defective problem. We will be happy to offer current standard card owner to upgrade to IEM card with discounted price and free shipping. We will post the link at head-direct website later this week so that you guys can follow. 
 
Best,
Fang

 

[kkcc]

Quote:

Hi Trogdor,
 
We have sold several thousand HM901 players in the world (we release 901 early 2013 in Asia). I hope you could understand that we will fell to bankruptcy if we change several thousand standard cards only after one card defective problem. We will be happy to offer current standard card owner to upgrade to IEM card with discounted price and free shipping. We will post the link at head-direct website later this week so that you guys can follow. 
 
Best,
Fang

 
 
Great offer!  Would be great for those who plan to only keep one card all the time.
 
But honestly the standard amp board is still very valuable in the lineup for a more laid back and cozzy sound sig and loooong battery life.  Having bought all the cards from hifiman, the std board and the balanced board are the ones I kept.     

 

[VisceriousZERO]

Long live HifiMan

 

[Mimouille]

Quote:

Thanks for KillerX's post. I have confirmed with him that it is a standard amplifier module damaging problem because his 901 line out is working fine. I do have a feeling it is a stupid problem that can be solved by burn in in factory, but we need to do more research other than burn in. I have called our manufacturing manager 5 min ago and we will check all of our stock standard card and make sure this problem will not happen again. We will check our AD8397 vendor about this problem as well and make sure it is not a chip problem. We are also working on QC procedures so that we can 100% get rid of defective amp cards before shipping. From now on we will buring in all amplfier modules for 48 hrs before shipping.
 
Because we can not ship standard card at this short period time, all customers who currently have pending 901 with standard card order will get IEM cards to replace standard card. 

 
Sir,
 
I was considering getting a 901 through your taobao page and this issue scared me as all my iems are over 1000 dollars. Can you guarrantee this cannot happen with any new 901 ?
 
Regards

 

[Nankai]

Quote:

 
Sir,
 
I was considering getting a 901 through your taobao page and this issue scared me as all my iems are over 1000 dollars. Can you guarrantee this cannot happen with any new 901 ?
 
Regards

 
Please make sure you buy from the following page if you want to order from taobao.com. This is our official order link in China. 
 
http://detail.tmall.com/item.htm?spm=a1z10.5.w4011-3385563530.54.QRBbHe&id=19662835291&rn=395839cd1667f1ffe97361e0ceecb022

 

[Mimouille]

Quote:

 
Please make sure you buy from the following page if you want to order from taobao.com. This is our official order link in China. 
 
http://detail.tmall.com/item.htm?spm=a1z10.5.w4011-3385563530.54.QRBbHe&id=19662835291&rn=395839cd1667f1ffe97361e0ceecb022

That is the one I had in mind. Thank you for confirming.

 

[fermelom]

This must really be my unlucky day. You guys won't believe what just happened!!

I fitted my RE600 into my HM901, on it, left side of the earphone started heating up seconds into the song in my ear followed by lots of distortion sound and i quickly detached it from the player.

left it for awhile to cool and when i plugged it in again, the driver on the left side apparently burnt out or something and there was no sound on the left side. I tried fitting the RE600 into my handphone and computer using the convertor and still no sound on the left side. Time to send it back...BUT ..thats not the end of the story...

I then tried using another Westone 4R on the HM901 and yes, you guessed it, no sound on the left side again. Tried fitting a headphone onto the player and no sound on the left either. SO NOW, i have got to send BOTH the HM901 and the RE400 back!! I was already worried when my device would heat up seconds into the song for now apparent reason and now my suspicions are confirmed. I am very very disappointed with this effort from Hifiman. This is my first purchase from them and to get not only one device busted BUT BOTH on the same day is really bad. 

Hopefully no one gets into the same mess as me. I was lucky that i pulled the plug out of the HM901 or who knows that thing might have exploded in my ear or something. Anyone who has gotten into the same mess as me?

I'm sorry what happened to you, fortunately Fang had take care of the situation, it's great to know that Fang himself is attentive of this issues.
About your expedience I would like to ask you if that was the very first time you used the hm901 or how many times or how long you used it before the problem. Since you turn on the player approx how long before the heating? Also if there's any visible physical damage in the amp module, like burned or something. I'm just asking to keep track of any undesirable behavior in my hm901.
At this time I only had issues with the response of the UI and some fine things about playback. I'm paying attention very close to post it later the most detailed that I could.

 

[KillerX]

Quote:

I'm sorry what happened to you, fortunately Fang had take care of the situation, it's great to know that Fang himself is attentive of this issues.
About your expedience I would like to ask you if that was the very first time you used the hm901 or how many times or how long you used it before the problem. Since you turn on the player approx how long before the heating? Also if there's any visible physical damage in the amp module, like burned or something. I'm just asking to keep track of any undesirable behavior in my hm901.
At this time I only had issues with the response of the UI and some fine things about playback. I'm paying attention very close to post it later the most detailed that I could.

 
Hi fermelom,
 
i have used the hm901 about 3-4 days and each time i use it it would heat up almost immediately, like after 1 or 2 songs. I treated it with care and used it only when i could disperse the heat properly (not in pants) from the unit. On average, i would use it around  1 - 2.5 hours each day. I would say i use it about at the most 12 times from the day i got it.  Physically there's no damage to the amp module, no melting parts. There is some burnt smell like what happened to the left side driver of the RE600 when the thing happened. I'm glad to be able to help to prevent any of this happening to anyone. But i can tell you that this happened way too suddenly and i used and treated it more carefully than all other things i have owned.

 

[Trogdor]

Hi Trogdor,

We have sold several thousand HM901 players in the world (we release 901 early 2013 in Asia). I hope you could understand that we will fell to bankruptcy if we change several thousand standard cards only after one card defective problem. We will be happy to offer current standard card owner to upgrade to IEM card with discounted price and free shipping. We will post the link at head-direct website later this week so that you guys can follow. 

Best,
Fang

Ah, makes sense. I just wasn't sure what you meant Fang. The upgrade option is very generous of you.

 

[jelt2359]

Kkcc, how would you compare iem vs standard card? I would assume battery life is quite similar.

Ps, I'm currently using the portaphile 627 as an amp with the hm801 as source (hm901 would be my first choice- but no cable.) It improves significantly on the 801 + game card. Mids also sound better than the balanced 901 (like you, I'm not so keen on the less prominent mids of the balanced 901 for vocal music), while adding a more 3d and airy presentation than the 901's single ended input.

PS Fang himself has always had the right attitude with customer service. Ms T always took care of me well too I guess their challenge would be to maintain this as hifiman grows in scope and size. All too often as companies get bigger, customer service is the first to suffer.

 

[KillerX]

Now i just have to think of what to do with the damaged RE600. Seems abit too wasteful to dump it into the bin. 

 

[VisceriousZERO]

Display it as a big heart in a frame with hifiman on the front of it.

 

[kkcc]

Quote:

Kkcc, how would you compare iem vs standard card? I would assume battery life is quite similar.

Ps, I'm currently using the portaphile 627 as an amp with the hm801 as source (hm901 would be my first choice- but no cable.) It improves significantly on the 801 + game card. Mids also sound better than the balanced 901 (like you, I'm not so keen on the less prominent mids of the balanced 901 for vocal music), while adding a more 3d and airy presentation than the 901's single ended input.

PS Fang himself has always had the right attitude with customer service. Ms T always took care of me well too

I guess their challenge would be to maintain this as hifiman grows in scope and size. All too often as companies get bigger, customer service is the first to suffer.

 
Never did a proper battery comparison but both last significantly longer than the balanced amp and I never ran out of juice during the day (or night) I had been listening to either.  IEM card sounded more neutral to me and stock card is more laidback.  Personally I think the IEM card do sound a lot like the balance amp in terms of signature and didn't warrant to keep both.  Based on your stated preference maybe you'd find std board more to your liking.  But then these are all subjective and why not just get them and keep whichever you like, if not all?  These are very easy to find their next buyer for minimal if any money loss.
 
Cheers