Dock Dual Thunderbolt 2 Laptops with dual hdmi out / dual screen sharing?

Question

I have a 2013 Macbook pro and a 2015 Macbook air. The pro has a busted screen but works fine otherwise, it has two Thunderbolt 2 jacks. The air is fully functional, it has one Thunderbolt 2 jack.

I like to make electronic music. I have some stuff on one Mac and some on the other. I have two displays I want to use. One is a older LG flatron with hdmi input, the other is a 4k uhd smart tv. I also own a 2tb time capsule.

In my head I'm thinking of a setup with the pro kinda always docked, maybe closed if possible, and always using the two displays, and a Bluetooth keyboard and trackpad controlling it or both, then I could just add the Air to the docking station whenever I wanted to and share files, monitors. I was thinking I could use one for like VST and plug ins and the other for my DAW host software. That way I could get the most computing power possible. Not sure if that's possible.

For a minute I was looking into DANTE or AVB but then that wouldn't solve my dual display needs.

I thought there has to be a dock that I can hook up both laptops to via Thunderbolt 2 and share data at high speed, with 2 hdmi outputs that I can also share between the computers. But so far I'm not finding anything. All I can find are dual monitor switches for mini display or Thunderbolt 3 / USB 3.1 docks with dual display but no dual hdmi. (I don't need to power the screens with hdmi).

So, I'm needing some help! I would like the added ports that a dock offers, I would like to quickly file share from laptop to laptop, and i would like to be able to, if possible, share dual external screens for editing and etc. Does anyone know how i can accomplish this? Any help is greatly appreciated!

Answer 1

A dock built to accommodate two hosts will be rare to non-existent. One reason is few people will want such a thing, and companies build devices for sale that they believe will bring a return on their investment, and another is that how such a dock should behave will be difficult to define, which makes the required investment in building such a dock quite high.

What you are likely going to have to do is build the dock you are looking for from more basic components. Perhaps a dock for each laptop and a KVM switch to flip the displays between the two computers.

There are software solutions that mimic the function of a hardware KVM, and these may be attractive for you on cost and/or convenience grounds.

Sharing data at high bandwidth will be rather trivial with a Thunderbolt cable between the two. A quick check of the specs on the two laptops tells me that driving what I assume to be two 4K displays may be too much for either computer to handle on it's own. To do this might mean driving one display from each laptop or adding an external GPU. Swapping the eGPU between computers is not likely to be trivial, you may have to pick which computer is driving the screens or have a separate eGPU for each computer.

You may not need a dock, or perhaps not need any additional hardware. What you need to do is define your goals more clearly and create your two computer system to match.

Here's one idea. The MacBook Pro can be "permanently docked" and have the two displays connected. The Bluetooth keyboard and mouse, and any other user input devices, also connected to the MacBook Pro. When you need to add in the MacBook Air then it would be connected to the MacBook Pro by a Thunderbolt cable. The Thunderbolt cable will provide a high bandwidth network between the two computers. Using a screen sharing program between the two computers you will be able to control the MacBook Air from the MacBook Pro.

How the screen sharing (effectively a virtual/software KVM switch) works with the MacBook Air will depend on the specific software used and it's intended behavior. To have the MacBook Air "see" the two screens on the MacBook Pro will likely require "dummy displays" to work. These "dummy displays" are video port dongles that will hang off the MacBook Air which will look like an attached display to the computer but have no real screen.

Sharing two high resolution screens will take a lot of bandwidth, even by Thunderbolt standards. Sharing data over this same network connection will take even more bandwidth. Spreading this out by using WiFi or some other networking connection will help in resolving what I anticipate to be a bandwidth bottleneck. Using a hardware KVM instead of a software KVM will mean not relying on a network to move the data for two 4K screens but dual 4K display KVM switches will not be cheap.

Buying the docks, KVM switches (hardware or software), and cables to make this work might end up being a considerable investment. So much of an investment that it may make more sense to just buy a new computer to replace the two you have.

Answer 2

I don't know of any dock that will support two laptops at the same time.

I have two suggestions:

• Use the Pro most of the time, have an external drive attached to the dock for file sharing. Shut down the Pro unplug the thunderbolt cable connecting it to the dock and plug in the Air when you need to. File transfer from the external drive through the dock should be fast.

• Assuming that a thunderbolt dock will have gigabit ethernet, use ethernet cables, hub, and a dongle to the air to network between the pro and the air.

Answer 3

You need a Thunderbolt 2 KVM Docking station like this product here:

https://www.aten.com/global/en/products/usb-&-thunderbolt/docking-switches/us7220/

It allows you to connect display, mouse, keyboards and other things (such as USB connected musical instruments or DACs) to the dock. Both computers are connected to the dock, and you can then switch between which of the two computers gets to use the peripherals using the buttons on top of the dock.

You wrote that you have a Bluetooth keyboard. It can become a hassle as that won't automatically switch over when you press the button (as it is not connected to the dock). I would advise using a cabled keyboard instead (if it is an Apple bluetooth keyboard, you can just connect a cable to it) - or possibly using a USB-Bluetooth dongle that is plugged into the dock for connecting it.

The dock has a HDMI port that goes well with your older LG monitor with HDMI input. The dock also has a Thunderbolt port which you can use to connect a Thunderbolt monitor at the same time.

NOTE: This particular dock does not support outputting HDMI signal AND mini-DisplayPort signal (display connected to the Thunderbolt port) at the same time. In order for twin displays to work this way, one needs to be a Thunderbolt display.