Yet another iPad charging question

[Harpman]

I just purchased the Focusrite Scarlett 18i20 for doing some multi-track live recording.  So here's my configuration

A1 -> Floor Monitor 1
A2 -> Floor Monitor 2
A3 (Vocals) -> CH 1 Input (18i20)
A4 (Guitar) -> CH 2 Input (18i20)
A5 (Bass) -> CH 3 Input (18i20)
A6 (Drums [Kick, Snare, OH]) -> CH 4 input (18i20)

I use an app on the iPad called "Auria" which through the USB connection kit on the iPad works great, except... It doesn't charge the iPad

Has anyone used a powered USB hub that can provide enough mA's to satisfy the 2100mA charging requirements.  I saw a Belkin 4-port USB hub that provides 4A (4000mA) but unsure if that will do the trick.  You would think someone at Apple would devise a connector like their HDMI connector where it does charge the iPad while connected to your HDMI monitor.
 

[RoadRanger]

Your confusion is that it is impossible to charge the iPad through the Camera (USB) Connection Kit. The iPad will actually power a USB device so the power is flowing the wrong way .
Apple sucks .

[Jerrylee]

RR your confusion is that you do not need the camera connection kit with Auria. There a plenty of hubs that connect directly to the 30 pin dock. And I also don't totally understand why a powered hub cannot be developed to charge the iPad as well as function as the audio interface. After all the docks like Alesis, behringer, and even the dl1608 can act as an audio interface as well as power the iPad. But only 2 channels. I don't know any hubs that can charge.

[RoadRanger]

RR your confusion is that you do not need the camera connection kit with Auria.

But you do with the Focusrite Scarlett 18i20 he is using .

[Harpman]

Attached is Auria's screen shot of approved list of audio interfaces, which clearly states that Auria doesn't require a "Powered USB Hub", but doesn't "Charge the iPad" either.  Really impressed with this app.  They just released 1.10 update today and it fixes and adds the following:

• Added MIDI Sync support with MTC, MMC and MIDI Clock options
• Added the ability to pass MIDI data the plugins
• Added MIDI remote control for controlling Auria with Mackie MCU and HUI control surfaces
• Added full MIDI MTC chase capability
• Mixdown e-mail option
• Added clip-based gain handle
• Added icon bar
• Added Delete All Automation on Track function
• Added "Link Locators and Highlight" option
• Added higher resolution grid lines when in bars:beats mode
• Added Load from snapshot if project fails to load
• Added snap to locators, markers and highlight
• Added tempo and time signature adjustments from the edit screen
• Reorganized settings screen into separate pages
• Various bug fixes

This will be the closest you will get to getting the DL1608 to do any kind of multi-track recording.

[Jerrylee]

RR your confusion is that you do not need the camera connection kit with Auria.

But you do with the Focusrite Scarlett 18i20 he is using .

Wrong again. You need a hub, but it does not have to be the camera connection kit. I use a $9 dollar hub bought on eBay.

[Harpman]

Your both actually correct. Two ways you can set this up.

1. USB Camera Connection Kit connected directly to the Scarlett 18i20 via the included Scarlett Scarlett Type "A" to Type "B" USB cable (The way I currently have it setup)
2. Using a hub with the 30-pin iPad-to-USB cable and the included Scarlett Type "A" to Type "B" USB cable

Either one will work 

[RoadRanger]

IME the cheapie non-Apple 30 pin to usb converters (even the powered hub type) give errors eventually. The only one that's been rock solid for me is the Apple one. But I use them for connecting a USB keyboard to my iPad 2, not a multichannel USB interface.

[WK154]

To get back to the OP "Has anyone used a powered USB hub that can provide enough mA's to satisfy the 2100mA charging requirements. " there needs to be a clarification on the intended purpose of the request. Are you looking for a means of charging offline (DCP = Dedicated Charging Port which Apple already supplies) or are you looking for a means to charge the iPad while in operation CDP (Charging Downstream Port)? The 2010 1.2 Battery charging spec for USB has many options. Do companies go outside the spec? The answer is NO except for Apple ( remember Apple only claims to be able to hook up with USB 2 devices and certainly is not USB certified). The limits on a CDP is 1.5 amps but you will be hard pressed to find any because the limit is the induced noise on ground for charging current ( sect 3.5 of the spec which limits it to 375mV). The Spec itself would actually allow up to 5 amps but it would exceed the 1.5amp limit imposed for each standard port. Once you exceed the limit you have 3 shutdown choices one of which is to provide constant current output (up to the safety limit of 5 amps). Does anyone make a device like this in volume? Again the answer is NO not even Apple. The best you could hope for is .9 amps for a USB 3 port but the USB 3 ID process would most likely drop you back to .5amps USB 2 on a CPD. If you are looking for a offline charging unit you already own one. It is well known that USB 2 ports will charge iPads even  if the iPad  states it's "not charging". Since Apple really doesn't state any conformance to USB it's hard to come to any conclusion other than by trial and error. RR throw in USB  OTG and tell me who is the host and who is the slave in this scenario?
"requirements"it's not, just a means to charge the iPad 3 in a reasonable time. I'm not getting into the different chemistry's of iPad batteries here.

[Harpman]

I was actually looking for CDP. I've settled for a Mophie battery charger that meets the 2100mA charging requirements, but of course is DCP not CDP and will have to disconnect one for the other if I need to recharge the iPad. Don't know if this will be any quicker than the supplied 12W DCP A/C charger. Just did a 3 hour gig last Saturday and had plenty of battery life to spare so I didn't need the Mophie or 12W A/C charger.

[Harpman]

Check this out!

http://www.kanexlive.com/usb3hub4x

Port 1 provides 10W of power for charging iPads.  Just purchased one at Best Buy.  Will keep everyone posted.