Which configuration works without downsampling?
[DSD bit-perfect wi-fi streaming to iOS instructions at the end of this guide]
The targets for 24 bit or DSD bit-perfect streaming in a portable setup:
compatible USB DAC/Amp (not any DAC will works regardless of price or recent release) battery powered or powered via battery powered USB Hub.
High storage capacity (500GB+) to save big high-definition files.
iPad or iPhone with no jailbreak and no DIY hardware mods.
Both Server and player easy to setup with at least cover arts and auto play next features (gapless not indispensable).
Internet connection or router not necessary.
iPad and iPhone have limited storage capacity, if you plan to use an app which plays only local stored files (stock player or Flac Player for usopported format) you'll limit your music collection, especially with big 24 bit or DSD high-resolution files.
Adding storage to the dock out connector isn't an option either since then you can't use USB OUT to output digital files to an external DAC.
ALWAYS REMEMBER: Any point in the chain could cause problems or downsample data, so you'll not receive a bit-perfect stream but just a downsampled to 16bit 44Khz version of your original higher resolution file.
Any piece of hardware, software, their settings, iOS version, files types, iDevice used,... ANYTHING must be selected and setted up properly to succeed.
Since iOS 7 both iPad and iPhone are now able to receive bit-perfect wi-fi streams up to 24/192Khz PCM or DSD, with older iOS only iPad could do it (without jailbreak).
To successful bit-perfect stream at least 24bit/96Khz files without downsampling to 16bit/44.1Khz in any point in the chain specific hardware and software configurations must be followed:
1) The 24bit/DSD USB DAC must have two features:
A) provide power via its USB PORT.
If its USB port do not provide power, we need to add a powered USB Hub in the middle.
B) don't require a driver to work at USB 1.1 specifications (up to 24bit/96Khz).
Some modern DACs work only with drivers even with lower resolution files, so they are USELESS here.
2) USB OUT connection via Camera Connection Kit (older iPads) or the newer Lighting to USB Camera Adapter.
3) Specific configuration of server software to bit-perfectly send streams.
4) Specific player app for iOS to bit-perfectly receive streams.
Most software (server or app) will not work or will downsample data to 16/44.1 regardless of settings. Capable software still needs to be configured properly.
For portability On The Go we need a portable battery powered high storage wi-fi UPnP/DLNA server (500GB+) with its budled server software capable of 24 bit-perfect wi-fi streams.
For portability at home there are more choices since wi-fi routers, high storage and lots of different servers are common.
Points 1) A) & B) are solved with a dedicated 24bit/DSD DAC made for iPad/iPhone : by specs it'll have a USB powered port and will work driverless.
Here a few dedicated products:
iFi Nano iDSD (DAC/Amp combo) tested and confirmed with DSD too!!!
Cypher Labs AlgoRhythm Solo (DAC only) officially supports 24 bit for iPad only (see page 7 of the FAQ not the manual), but needs to be confirmed by users, testing its own digital coax out to an external dac able to display bit/samples effectively received.
CEntrance HiFi-M8 (DAC/Amp combo) officially supports up to 192Khz, but I think only 96Khz for iPad, without digital out can't be tested with an external DAC able to display bit/freq.
Sony PHA-1 (DAC/Amp combo) officially supports up to 24/96, but without digital out can't be tested with an external DAC able to display bit/freq.
There are a lot of other dedicated DACs for iDevices, but they're limited at 16 bit / 44.1 KHz.
Without a dedicated iDevice DAC be careful since not any USB DAC/Amp powered unit works, it still could miss Point 1) A) (do not provide power via its USB port, so a USB Hub in the middle is necessary) or Point 1) B) (it won't work driverless at USB 1.1 specs).
If the USB DAC provide power via its USB port, but does not works driverless up to 24bit/96Khz it WON'T WORKS.
A few examples:
- The M2Tech Young DAC is a powered desktop USB DAC, but it works only with drivers, so it won't work with iPad/CCK USB out.
- The iBasso D7 portable USB DAC/Amp isn't powered and iPad is unable to power it, but it works driverless at USB 1.1 specs, so adding a USB powered Hub it works.
- The Antelope Zodiac is a powered desktop DAC, it will works up to 384Khz with drivers, but also up to 96Khz driverless and it has a powered USB port, so it'll works without the need for a USB Hub.
Note: some USB DACs that works are unable to process some sample rates (192khz max but no 88.2 or 176.4 Khz support), it depends on the USB chip and number of clocks installed. So you can't play files at the unsupported frequencies.
To save battery power since latest iOS iPad always checks the power request of the USB port of the attached device (USB DAC) indipendently if it's a powered unit or not.
If the USB port of the device is powered or could be powered at 20mA MAX, USB Out will be active, if not USB Out will be disabled.
If the USB port of the DAC doesn't provide power we need a USB Hub in the middle to do the trick.
With a powered USB Hub any of its USB ports will provide power; if the USB Hub is unpowered you must add a USB battery charger to power it; if it could be powered up to 20mA MAX it'll be powered directly from iPad which is the best solution (like the Unitek USB Hub cable).
Most portable USB chargers are not Hubs, data pins are not connected so they provide only power; a few are able to pass data exclusively via USB OUT and not via mini USB IN used to recharge. So at least two USB OUT are needed (1x iPad, 1x USB DAC) making them real Hubs.
The old solution to use a USB "Y" cable (one of the three ends is power only) to provide power to the USB DAC doesn't work anymore, with the latest iOS, iPad will check power requirements of the USB device asking data.
Here a few portable 24 bit USB DAC/Amps which need power via USB Hubs but work driverless (up to at least 96 Khzbut):
Meridian Explorer up to 192Khz + point 3).
iBasso D7 up to 192Khz but not 176.4Khz + point 3).
CEntrance DacPort up to 96 Khz + point 3).
Audioquest Dragonfly up to 96 Khz, reported working without point 3) but still to be confirmed with latest iOS firmware.
HRT microStreamer up to 96 Khz, reported working without point 3) but still to be confirmed with latest iOS firmware.
Here a few USB Hubs battery powered or USB chargers with at least two USB OUT) or Udirectly powered from iPad/CCK up to 20mA MAX:
Unitek USB cable with Hub: powered directly from iPad/CCK USB out, is avaiable with different connectors to USB DACs (USB female, male mini USB and male micro USB) the male USB-A connector must be plugged to iPad/CCK.
NOW DISCONTINUED? The US eBay link is no longer avaiable http://www.ebay.com/itm/USB-2-0-90-degree-angled-male-to-2-female-extension-data-hub-rainbow-color-cable-/110855033353?pt=US_Video_Game_Cables_Adapters&hash=item19cf799209. If you are in eBay Italy search "prolunga USB HUB" and you could find it.
There are similar types around, but they must be tested to confirm they're Hubs.
On Lite H420B: 4 rechargeable batteries that you can change/add at will (NOT WORKING RELIABLY).
D-Tech solar/battery powerd USB Hub (4 USB, 1 mini USB): solar power not capable to feed USB DAC/Amp, battery last 1 hour max.
Tekkeon MP1860A (2 USB OUT, 1 mini USB IN) USB charger + data pass (still to be confirmed).
This picture shows a working setup with a not native iDevice and not battery powered DAC (iBasso D7) connected with portable USB charger (Tekkeon), USB Hub cable (Unitek) and LtUSBCA.
For portability On-The-Go we need a portable battery powered high storage wi-fi UPnP/DLNA server (500GB+) with bundled server software and player (or able to use a third-party app) capable to stream 24 bit-perfect data.
Most portable servers have limited software configurations, generally they can't transcode/convert files (FLAC or DSF/DFF) to a iOS compatible format, but if you convert your FLAC and DSD files to ALAC or DoP ALAC (see DSD below for configuration details), you'll have a high definition portable setup.
Add a UPnP/DLNA player app for iOS like 8player and your're ready to receive bit-perfect streams.
Remember, most players won't work at 24 bit-perfect and will downsample to 16/44.1 the incoming data, have bad file support and miss fundamental features (background play, play while browsing library, play on the fly, auto play next, cover arts,...).
PlugPlayer or AceMusic players for example always downsample regardless of wi-fi type, streaming server settings and configs used.
I'll update the list here for any UPnP/DLNA player app working 24 bit-perfect and have most fundamental features:
Here a few capable portable UPnP/DLNA servers:
Seagate GoFlex Satellite (500GB, latest FW can use internet while streaming) or the newest Seagate Wireless Plus (up to 2TB) works with bundled software and is able to stream any files the iOS supports or files supported by third-party apps. It has some DLNA capability (but not fully certified).
Buffalo MiniStation Air (500 GB) not yet released and incomplete infos, will come with its iOS dedicated app.
Patriot Gauntled Node (hard disk not included, you can choose storage capacity), is confirmed not working bit-perfect with bundled software (zzffnn reported working with SAMBA streaming which, even if bit-perfect possible, is rouled out=long start up time, too long loading each file, no cover art, no background play, no browsing while play,...).
For portability at home we have more choices since there are lots of server software avaiable built in a NAS or a computer system.
My favourites are:
a) Logitech Media Server + iPeng Player (audio only. In-app purchase needed, no need to have a Logitech device).
b) JRiver Media Center or any similar DLNA/UPnP server + 8player.
c) iTunes Home Sharing + stock player (audio/video but only for officially supported iPad formats).
All setups are tested using external DAC able to display bit/freq received and which does not resample incoming data.
For music only, LMS/iPeng is the best configs right now at home: great sound quality, FLAC support (no need to convert files neither in the server), cover arts in any directory, better browser organization and faster interface,... Sound quality differences are not strange since any software player do something in a different way (JRiver, Foobar, WMP, iTunes, JPlay,...): bits are not just bits in digital audio, "time" matter a lot.
BUT iPeng officially will never support UPnP/DLNA and LMS is not installed in any portable battery powered wi-fi server.
FLAC is not supported by iOS so you need to setup the JRiver or similar DLNA/UPnP server to transcode FLACs to ALAC or WAV or you must convert all your FLAC files.
iTHS/stock iPad player isn't a good solution: limited formats support and a really bad interface.
Other iDevices (without jailbreak) are generally limited to a max official support of 24 bit / 48 Khz, which could be fine, but without a CCK, you need a desktop digital dock which is not portable neither at home or a dedicated iDevice DAC/Amp.
iTHS/stock Apple player is limited to 16 bit for iPhone/iPod touch.
LMS/iPeng officially support 24/48 for iPhone/iPod Touch, but needs to be confirmed.
Cypher Labs AR Solo supports 24 bit for iPad only, but could works, a direct test needed from its digital coax out.
Sony HPA-1 supports up to 24/96 but it's uncertain if it's for iPad only and without a digital out it's impossible to check.
Fostex HP-P1 was potentially a good choice (32 bit DAC/Amp combo) but it's limited at 16/48 and iPad not even supported (even if reported working at 16 bit).
iPod Classic 160GB (without wi-fi and third-party apps) works with 24 bit / 48 Khz files only in the sense that it'll be able to play them but it will always downsample to 16 bit before reaching the DAC section.
VentureCraft Go-DAP 4.0 will always downsample to 48Khz (thanks to AnakChan for reporting).
I'll update any possible portable 24 bit solution for other iDevices here:
BIT-PERFECT DSD WI-FI STREAMING TO iOS
There are two very important advantages using native DSD wi-fi streaming to iOS beyond the obvious better sound without a conversion in the middle from DSD to PCM.
If the server is not capable to filter the ultrasonic noise typical of DSD converted to PCM, you could damage your hardware or ears! Instead a native DSD stream will be perfectly safe.
If the server converts on-the-fly DSD to 24bit PCM, the wi-fi band will be overtaxed, maybe exaggerating the problem due to the ultrasonic noise, and you can't play big files (over 10 min): you'll have skips and stops or not able to play anything at all. Instead big native DSF files streams are not a problem.
1) Using a DSD over PCM Ethernet Server (DoPE Server) (like JRiver MC)
To stream native DSD file to iOS you could use a server like JRiver MC or similar which could be configured in DoPE mode:
Go to TOOLS>OPTIONS>MEDIA NETWORK>ADD OR CONFIGURE DLNA SERVERS... and
1) in AUDIO/MODE: select ORIGINAL or it'll convert to PCM.
2) in ADVANCED (the second entry not the first "Advanced") check "Bitstream DSD (requires DoPE compliant renderer)" or you'll get white noise.
Use 8player app on iDevices to play DSD files from it bit-perfectly!
2) USING a wireless storage portable server (like Seagate Wireless Plus or LaCie Fuel)
Since these portable devices are not DoPE servers we need to convert those DSD files to DoP (Digital over PCM) ALAC to wi-fi stream native DSD to iOS devices.
Use Foobar As A DSF to DoP File Converter
NOTE: Foobar will be only used as a file converter, not as a media player.
If you want to restore it as a player remove the 'foo_input_packeddsd.dll' component and return to the standard SACD 0.7.1 component.
1. Install Foobar2000: http://www.foobar2000.org/
2. Install the foobar2000 free encoder pack: http://www.foobar2000.org/encoderpack
3. Download the "foo_input_packeddsd.dll" file and place it in the C:\Program Files\foobar2000\components folder: https://docs.google.com/file/d/0B4jZ4NDGECzEczBjYVByNUdjdDg/edit
4. Start Foobar and go to "File->Preferences ->Components" to make sure "foo_input_packeddsd.dll" shows up in the installed components box.
5. Go to "File->Preferences ->Tools->SACD" and set the following configuration:
ASIO Driver Mode: DSD
PCM Sample Rate: 176400
DSD2PCM mode: DSD over PCM
Click on "Enable Tags"
Note: Foobar may need to be restarted for these setting to load for conversion.
6. Use "File->Open” to load DSF or DFF files for conversion into a Foobar playlist. Highlight all the files in the playlist, right click and select "Convert". Choose the “…“ option.
Set FLAC or ALAC as the output format.
If you've installed only FLAC Frontend: http://download.cnet.com/windows/seek-s-encoder-frontends/3260-20_4-10055779.html?tag=rb_content;contentBody the first time you run conversion you will be prompted for the location of FLAC.exe. Most likely it’s in C:\Program Files\FLAC Frontend\tools.
Set other conversion options (output folder, file name pattern, etc.) here. My preference is to set the sub-folder name to “artist - album” and file name to “nn. title”.
7. Hit the “Convert” button to begin the batch conversion process.
8. Some DSF metadata will carry over to the DoP file but cover art will need to be reattached. Cover art and metadata in the DoP file can be edited just like any other file. I add “(DSD DoP)” to the end each folder name and album title to differentiate it from the same album in other formats.
9. Before batch converting a bunch of files, convert a few test files and play them to make sure they decode as native DSD.
10. If the files don’t play back correctly, Check the following:
Verify that all four parameters on the "File->Preferences ->Tools->SACD" Foobar screen are configured as documented above.
In order for DoP files to play back properly with a compatible DAC, the files must be streamed as bit-perfect PCM. This means that the software volume control must be at 100% and there should be no DSP plug-ins in the PCM streaming path.
(thanks for the help to seeteeyou, whodiini and Russtafarian)
Edited by Thraex - 1/23/17 at 5:59am