Hacking the Dock Connector on the DL1608

[cgecastro]

Hello everyone!
Is there a way to use the dock conector audio inputs without having a device pluged in?
The idea would be to use the inputs as 2 extra line level channels.
Don't know if the audio is played back digitaly via USB or if it is analog?
If it's analog it migh be simply the case of making a couple of holes and pigybacking a couple of RCA plugs or a minijack
Does anyone have any ideas before I start dissasembling my DL1608?

[Wynnd]

My idea is this won't be as easy or cheap as you think it might be.   I'd be looking around for a DL806 cheap instead.  Then you will have 23 available channels. 

[WK154]

The wired connection audio is digital send via "secret sauce" according to BenO. Time to move to something bigger and not necessarily Mackie.

[cgecastro]

Well back to this...
Audio is digital but the "sauce" can not be great because when you plug the ipad to the DL1608 the iPad "reads" the DL1608 as a USB audio interface.

My guess is:
The ipad uses generic USB Audio Interface drivers to input and output audio when it connects to the DL so the DL has to present itself as a USB Audio Interface
The audio is USB audio the "sauce" I think is only for the control part.
Once you plug the ipad to the DL the dl signals the ipad to switch to USB host mode, as would happen when you connect a Camera Connection Kit

I am now trying to connect my mac to the DL to see if it detect the DL as a audio interface.

[WK154]

So what is your results? I tried that with a PC a long time ago and it detected nothing.

[cgecastro]

Still bouncing ideas off a wall... Will try a few of them tonight

[cgecastro]

So what is your results? I tried that with a PC a long time ago and it detected nothing.

Partial success!
I removed the tray, removed both cables from the dock connector, removed the dock from the tray.
The 5 pin connector labeled J2 and with a round cable Is the USB connector the colors of the wires apear standard since i cut a usb cable and the colors are the same.
Connected all wires to a breadboard and my cut usb cable to the corresponding wires. I jumped the two black wires as they are also jumped on the DL dock connector

Plugged USB to computer and nothing happened.... the computer would not detect the DL1608

Next I plugged the ribbon cable back into J3 on the DL dock connector and plugged the iPad into the dock. The usb part was still connected to the the previous setup.
At this point the DL showed up on the mac as one USB device named  Mackie DL1608 and two Audio devices both named ZeroBandwith one 2 channel input and the other 2 channel output
They are selectable on Audio Preferences and on the Audio Midi Setup app.
A level does appear but i need to test further
Downloading garageband for further testing

Hopefully the iPad can be spoofed so that it is not required.
I will try to post pics as soon as I learn how to

[cgecastro]

Picture of the setup and of the System Profiler screens.
Usb devices and Audio Devices

[pytchley]

Interesting but the photos don't shop up on my mac... am I alone?

[cgecastro]

Any suggestions for photo hosting?
Is this working?

https://share.icloud.com/photos/06vOGbVS55FhLqYMDC5t0aIbA

[WK154]

A lot of this was done 7-8 yrs ago here for slightly different reason. Here is the pin-out of the paddle board.  http://cacophony.aspinock.com/index.php?topic=464.msg3462#msg3462 The quasi USB output doesn't comply with the USB spec which typically would allow 3 Meter cable. You're lucky if you can get 30" for a extender to the paddle board and only if you have a fully charged iPad otherwise you will loose the connection. Tying chassis ground to signal ground is another poor engineering job by Mackie as is their power-supply.