[twister6]

Yep, I agree.  My only suggestion if they can implement in firmware a low/high gain setting.  Right now it's in high gain with 2.2Vrms output which kills my high sensitivity headphones (ZA Doppios) with a background noise.  If they can have a selection for low gain to cut down on output level, it would help a lot to reduce this amplified noise.

 

[lee730]

So not good for sensitive IEMs I take? To bad high gain can't be implemented with low noise floor. I tend to enjoy higher gain even with some IEMs just the noise it induces.

 

[AlexRoma]

Ok, Hidizs is't that great on sensitive IEMs, but even so, on my IE80 it sounds way smother & bigger then the brutal X5. 

 

[twister6]

It's not that terribly bad.  In my case I'm using ZA Carbo Doppio which has 113dB/1mW sensitivity (12 ohm impedance).  AP100 is rated at 2.2Vrms (probably at lowest impedance), but still it will be a pretty high power output even with 12 ohm load.  So with such high output power and high sensitivity whenever AP100 is idle you can hear a faint white noise in the background.  It did get a little bit better after 25hrs of Doppios burn in, and might get better since a lot of people suggesting 100-200hrs burn in for ZA headphones.  But nevertheless, it is noticeable now because I use Doppios a lot.  I wonder if I can use some in-line 3.5mm attenuator to reduce that.  Another option is to use external DAC/amp to control gain out of LO of AK100, but then you loose SRC setting  since it only applies to HO output.
 
I'm going to continue pinging Hidizs guys to implement low/high gain setting in firmware

 

[reihead]

Any info about future firmware updates? It will support 128gb mSD cards?

 

[ozkan]

  Any info about future firmware updates? It will support 128gb mSD cards?

Are they planning the add high/low gain optinon in the menu? I'm quite interested in this beautiful retro-looking dap and wonder if they will support new firmwares. I recently bought a Hm601 just before I saw Ap100. I don't know if I gave the right choice or not.
 
It would be nice if there is someone who can compare Ap100 to Hm601 and Dx90.

 

[twister6]

  Any info about future firmware updates? It will support 128gb mSD cards?

 
Still waiting for the official reply...  To be honest, if you have a huge music collection where in addition to internal 8GB memory and 64GB expansion you need a lot more space, X5 might be a better choice with 2x 128GB + OTG, though sound quality will be a step (not a huge) down from AP100.
 
Btw, Penonaudio guys informed me that anybody purchasing AP100 from their on-line store or ebay store before June 30th will get 10% refund ($30 refund credited back).  Also, Hisound PAA-1 (regular, not Pro) will be included as a free bonus, along with a leather case and headphone adapter.

 

[Luvdac]

anyone know if it supports DSD (dsf or dff files)? X5 and dx90 play them after conversion to pcm 24/88. I like the comments about the musicality of this player. In the digital age we very often get carried away by the numbers and overlook the actual musical presentation that the player is capable of. If it does dsd and 128 gb sd cards, I'm in!

 

[twister6]

  anyone know if it supports DSD (dsf or dff files)? X5 and dx90 play them after conversion to pcm 24/88. I like the comments about the musicality of this player. In the digital age we very often get carried away by the numbers and overlook the actual musical presentation that the player is capable of. If it does dsd and 128 gb sd cards, I'm in!

 
As of now, DSD is not supported.  128GB is under question, I heard they might be testing it.

 

[Jerryberry]

How does this up sampling function work to actually improve music quality ? Does it also improve music files across the board regardless of type and even of poorer quality ?

And without this so called magic button, how does it compare with the x5 ? I just want to make sure it isn't some sort of a gimmick or artificial boost ?

 

[goodvibes]

Upsampling usually involves some trade offs depending on how much interpolation is taking place. It's often not a symmetrical upsample as 44 is not a multiple of 96 or 192. Generally, you'll prefer native rate or the highest upsample selection. 192 will often sound more open and refined due to filtering differences but can have less boogie factor than native.

 

[goodvibes]

  It's not that terribly bad.  In my case I'm using ZA Carbo Doppio which has 113dB/1mW sensitivity (12 ohm impedance).  AP100 is rated at 2.2Vrms (probably at lowest impedance), but still it will be a pretty high power output even with 12 ohm load.  So with such high output power and high sensitivity whenever AP100 is idle you can hear a faint white noise in the background.  It did get a little bit better after 25hrs of Doppios burn in, and might get better since a lot of people suggesting 100-200hrs burn in for ZA headphones.  But nevertheless, it is noticeable now because I use Doppios a lot.  I wonder if I can use some in-line 3.5mm attenuator to reduce that.  Another option is to use external DAC/amp to control gain out of LO of AK100, but then you loose SRC setting  since it only applies to HO output.
 
I'm going to continue pinging Hidizs guys to implement low/high gain setting in firmware

You shouldn't lose the src on lo but likely do on dig.

 

[Jerryberry]

Upsampling usually involves some trade offs depending on how much interpolation is taking place. It's often not a symmetrical upsample as 44 is not a multiple of 96 or 192. Generally, you'll prefer native rate or the highest upsample selection. 192 will often sound more open and refined due to filtering differences but can have less boogie factor than native.

Boogie factor ?

 

[twister6]

Just checked it again, with headphones connected to LO (using Tenores), cycling through SRC presets doesn't change the sound quality, while connected to HO it does.  And it makes sense because intent of Line Out is to do post-processing of digital output with external amp/DAC.
 
Btw, Penonaudio officially added under their listing: http://penonaudio.com/Hidizs-AP100 that if ordered by June 30th, you will receive 10% cash back ($29.99 credit back to your account after purchase).  The same applies to the purchase from their eBay (http://stores.ebay.com/bigbargainonline/) store.

 

[goodvibes]

LO will be after the DAC. Upsampling happens before the DAC. Dig out would be before the DAC. The physical commonness of the jack has no influence of how the 2 portions of it's function would behave. Anything is possible and I'm not saying you're wrong but it would seem improbable that it doesn't upsample the LO while upsampling the HO with only one DAC path.