Fostex HP-P1 Portable Amplifier and DAC for iPod/iPhone (Short REVIEW and Impressions Thread) - Page 47

Quote:

Originally Posted by Lillee 

Yes Fostex accepts and works with 24/48 ALAC files but I am pretty sure it down samples this to 16/44 as I cannot tell the difference between same file at 24/48 and 16/44.
I use a 240gb iPod 7th gen. Mod kit or completed mods are readily available on eBay.
Yes I think to a certain point a good USB LOD is better than a cheap USB LOD. The way i understand it is that data being transmitted in music format which is bit for bit in real time is not the same as digital file transfer, I doubt the former has any error checking at all and is prone to loss whereas the latter has much error checking built into send and receive ends to preven file corruption. Therefore rf interference and other factors do play a role in data transfer in digital audio. But I feel after a certain quality it's less relevant. Happy to be proven wrong though.
Was there anything else I missed in your post? I read all 350 pages of ES5 thread before receiving mine so 40 pages is lightweight!!!!

LOL (for the 350 pages...just 46 upsets me a little!) and thanks for the reply Lillee, but you've not answered my question.

I already know the iPod Classic alone accepts and works with 24 bit / 48 Khz files (higher samples can't be loaded), but it plays them downsampled to the built in dac.

I'm searching the proof that with the Fostex HP-P1 digital optical out the iPod could effectively send to an external dac the 24/48 files.

Maybe 24/48 vs 16/44 is not such a big difference by ear but I want to be sure about it!

And what about the iPad?

As anybody knows now, it could send bit perfect 24/192 files to USB DACs with configurations similar to mine explained in my previous post.

Can the Fostex do the same without the CCK connected to the iPad?

Regarding cables and such I'm a cable guy in both analog and digital domain.

In digital audio they're not just bits (0 or 1) and the explanation is there's also "time" which change the battlefield a lot.

In analog the explanation is even more easy any cable is different: copper/silver/carbon, dielectric, connectors, length, diameter, inductance, capacitance, .... so they're not all the same and anyone sounds different from the other (more expensive not means always better, its more system dependant).

What I dont understand is why anyone is discussing about changing cables for better ones and nobody cares about checking file resolutions which are the real source!

I repeat my question still to be answered:

Which bit/sample rates the Fostex effectively receives from iPod / iPad checked by using its digital optical output to an external dac which displays bit/sample rate?

Anyone is so kind to check it please?

I have an Ipad 3, but never really tried it with 24/192 sorry. Suppose I can give it a whirl tonight...

It is likely that the DAC chip is capable of 24/192 being a 32 bit DAC? but I suspect (and that's a big assumption) it is limited by the proprietary iPod decode algorithm (that Fostex and Cyber Labs have paid big bucks for) which is limited by Apple itself to 16/44. Otherwise why else would the two companies limit this 16/44? it makes no sense if the DACs are capable of this higher end decoding.

Also a little bird told me that the AKM AK4480 DAC that is in the Fostex actually has a balanced line out on the chip interface but is not being utilised by Fostex. (that's right, it is capable of balanced line out, one for L one for R). You heard it here first.

I very much doubt that the output of the optical is anything other than 16/44 and would be pleasantly surprised if it was any higher... I actually have digital interface on several items, maybe should do some testing lol

dunno if this is helpful. (posted before)

Playing a 24/96 file using flacplayer beta in February through a Fostex(ipod touch 4G shows small statistics with or without the Fostex)

http://www.head-fi.org/image/id/2417240/width/400/flags/LL

<a href="http://www.head-fi.org/gallery/image/view/album/120193/id/512403/sort/display_order"><img src="http://www.head-fi.org/image/id/2417240/width/400/flags/LL"></a>

Quote:

Originally Posted by ExpatinJapan 

dunno if this is helpful. (posted before)

 

Playing a 24/96 file using flacplayer beta in February through a Fostex(ipod touch 4G shows small statistics with or without the Fostex)

 

 

http://www.head-fi.org/image/id/2417240/width/400/flags/LL

<a href="http://www.head-fi.org/gallery/image/view/album/120193/id/512403/sort/display_order"><img src="http://www.head-fi.org/image/id/2417240/width/400/flags/LL"></a>

Thanks but not really helpful.

iPod iPhones and iPads are all different in some ways and I'm more interested in iPod Classic 160GB for higher storage and iPad which is proved the only solution till now for high res files with CCK and some USB DACs.

BTW for iPhones also Home Sharing vs Flac player and such to check if small statics are the same at the same resolution, and Flac Player was updated since beta. Maybe 24/48 is the limit could be loaded like my iPod Classic?

Quote:

Originally Posted by Lillee 

I have an Ipad 3, but never really tried it with 24/192 sorry. Suppose I can give it a whirl tonight...

 

It is likely that the DAC chip is capable of 24/192 being a 32 bit DAC? but I suspect (and that's a big assumption) it is limited by the proprietary iPod decode algorithm (that Fostex and Cyber Labs have paid big bucks for) which is limited by Apple itself to 16/44. Otherwise why else would the two companies limit this 16/44? it makes no sense if the DACs are capable of this higher end decoding.

 

Also a little bird told me that the AKM AK4480 DAC that is in the Fostex actually has a balanced line out on the chip interface but is not being utilised by Fostex. (that's right, it is capable of balanced line out, one for L one for R). You heard it here first.

 

I very much doubt that the output of the optical is anything other than 16/44 and would be pleasantly surprised if it was any higher... I actually have digital interface on several items, maybe should do some testing lol

Thanks Lillee!!!

Please try both iPod Classic and iPad so I don't have to read another thread maybe with 350+ pages!!!

I must add that I checked the Cypher Labs Solo faq (not the manual) and for iPad it is stated 24 bit!!! (page 7)

http://cypherlabs.com/images/pdfs/Cypher_Labs_AlgoRhythm_Solo_FAQ.pdf

Quote:

Originally Posted by Thraex 

I must add that I checked the Cypher Labs Solo faq (not the manual) and for iPad it is stated 24 bit!!! (page 7)

 

http://cypherlabs.com/images/pdfs/Cypher_Labs_AlgoRhythm_Solo_FAQ.pdf

Great find! I that is news to me (and I am sure alot of people)... needs further investigation

That's why i have the fostex HP-P1 and a Hifiman HM801.  That way i have capacity when i want it but if i need to play 24 bit files, the HM801 takes over.  Gotta say though, i got the HM801 first, before the Fostex was released and only got the Fostex later for the ease and compatibility that comes with idevices and has good audio quality too.  Sorry run on sentence but you get it.

Quote:

Originally Posted by m2man 

Apple's protocol that your iDevice uses to talk with the HP-P1 only supports 16/48k as it's max.
You'll have to get a desktop DAC/AMP to get 24 bit. You're not going to hear any 24 bit differences on the HP-P1 anyway. It's detailed, but it's no where close to 24 bit detailed.

Sorry m2man, but your answer needs to be much more precise and detailed or you'll confuse things a lot more:

1. iDevices are not all the same. iPad (but not iPhone/iPod) is able to send up to 24 bit / 384 Khz using CCK to some USB DACs ( see example here http://www.youtube.com/watch?v=3Modabpck0Q in which they just use stock Apple music player built in. Flac Player is officially approved and supports unofficial FLACs but it can't be loaded in iPods). Do you mean this way iPad doesn't use Apple protocol? OR do you mean ANY iDevices only with the HP-P1 are limited to 16/48 while the Cypher Solo can do officially 24 bit? (See here http://cypherlabs.com/images/pdfs/Cypher_Labs_AlgoRhythm_Solo_FAQ.pdf page 7). OR do you mean any iOS update or Fostex HP-P1 HW and FW revisions will never change things you stated?

2. I don't have to use a desktop DAC/AMP like the example before to get 24 bit with iPad, I use a CCK + USB battery powered hub (D-Tech or Tekkeon) + a portable iBasso D7 USB DAC ( see here http://www.ibasso.com/en/products/show.asp?ID=77 ). To be more precise not ANY desktop DAC/AMP are able to receive 24 bit from iPad + CCK just because they're powered, they need to comunicate to the iPad that they've a powered USB and some do not and will not works! Even more: USB 2.0 chips (able to go higher than 96Khz) built inside ANY DAC must support even USB 1.1 standard WITHOUT a driver or iPad will not work at all (for example my desktop M2Tech Young USB DAC which can do 32/384 with a driver won't work with iPad at all TESTED MYSELF!)!!!

3. I don't care if I'll be able to hear sound differences I want to know if HP-P1 does pass high resolution files via optical out to an external DAC which displays bit/sample rates!!!

4. Regarding officially supported features: You need to TEST IT YOURSELF to check which features are functioning in reality!!!

   A fine example is my Yamaha NP-S2000 streamer (go here http://usa.yamaha.com/products/audio-visual/hifi-components/network-players/np-s2000/?mode=model and look under specs) officially it does't support 192 Khz FLAC or even just ALAC (BTW ALAC is limited to 24/96 TESTED MYSELF!) but it does in reality! Its dysplay always show the same type/bit/samples of original files and I double checked it by using its digital out to an external DAC able to disply bit/sample rates. NOWHERE IN THE WEB I'VE READ THESE FEATURES ARE SUPPORTED OFFICIALLY OR EVEN MENTIONED IN SOME REVIEWS OR FORUMS!!! So nobody knows it can do 192 with FLAC which is one of the main reason Linns and Naims players are famous for! (BTW it does sound fantastic compared even to those TESTED MYSELF!!!). It's even supposed to work only with it's dedicated app but it works even with PlugPlayer or Linn own Kinsky app (TSETED MYSELF!!!!), only the internet radio feature must use it's dedicated Yamaha app. Officially supported features means just a little because some updates are not reported nowhere even by the same manufacturers, and some clever guys always try to add unofficial features which are great.

So in case my question wasn't clear I try to reelaborate it more in details:

ONLY using the Fostex HP-P1 (HW and FW version please) built in DIGITAL OPTICAL OUTPUT connected to an external dac able to display bit/sample rates, which are the MAX bit/sample rates the external dac displays using which iPhone / iPod / iPad (versions, iOS, file type , app and config used please) CHECKED/TESTED BY YOURSELF?

I can re-elaborate my question further if it's not clear...

You can try writing to Fostex yourself to get an answer instead of shouting at us... just a thought

Quote:

Originally Posted by Lillee 

You can try writing to Fostex yourself to get an answer instead of shouting at us... just a thought

Sorry for shouting, you're right, I will be more polite from now on, it happens sometimes one behave in a wrong manner...

Pardon me please.

I've wrote to Fostex a few times but no reply.

Is anyone so kind to answer my question here?

Lillee, haven't you done any test as reported before?

Thank you!

Quote:

Originally Posted by Thraex 

Sorry for shouting, you're right, I will be more polite from now on, it happens sometimes one behave in a wrong manner...

Pardon me please.

 

I've wrote to Fostex a few times but no reply.

 

Is anyone so kind to answer my question here?

 

Lillee, haven't you done any test as reported before?

 

Thank you!

It is a few weeks off, but I can ask the Fostex guys at RMAF in October when I see them.

Quote:

Originally Posted by longbowbbs 

It is a few weeks off, but I can ask the Fostex guys at RMAF in October when I see them.

Thanks, I hope someone is so kind to test it sooner...