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 MBP has a busted screen but works fine otherwise, it has two Thunderbolt 2 ports. The Air is fully functional, it has one Thunderbolt 2 port.

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 MBP is always docked, maybe closed if possible, 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 and monitors.

I was thinking I could use one for like VST and plugins and the other for my DAW host software. That way I could get the most computing power possible. I’m 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 DisplayPort 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 Ican accomplish this?

Answer 1

The system bumped this question and in that time product offerings have changed which means I offer an alternate answer. The answer I gave earlier was the best advice I had at the time, and to some extent is still good advice today. This is an attempt to offer an answer that is not only more up to date but also simpler and less wordy.

Option One:

Thunderbolt 2 devices today are rare and when you can find them are quite expensive, which no doubt has something to do with the rarity. Now one is likely going to have to buy Thunderbolt 3 devices and an adapter for Thunderbolt 2. To share two HDMI screens with two computers with Thunderbolt 2 ports would mean getting two Thunderbolt 3 docks, two Thunderbolt 3 to Thunderbolt 2 adapters, and a dual HDMI KVM switch. Then to share files between the computers would mean docks that have Ethernet and connecting those ports by an Ethernet cable, or providing a data path between the computers separate from the dock. That means buying Ethernet adapters, using peer-to-peer Wi-Fi, or some other kind of hardware. This collection of hardware could easily cost over $1000.

Option two:

Buy a new laptop. You have a laptop that is getting to be 10 years old and already has a broken display, it's likely to be cheaper to replace the laptop with one more capable than to buy the necessary hardware to overcome it's shortcomings. This won't remove the need to buy some cables and accessories but this does mean buying adapters off the shelf for $15 than special order items for ten times that price. This won't exactly solve your screen and file sharing issue with the older laptop(s) but by learning to use the included Apple utilities for screen sharing and file sharing, as well as the built-in Wi-Fi and/or Bluetooth, you should find things quite speedy and convenient without additional hardware. If you do need hardware then, again, it should be common items that are low in price but still high quality and reliable.

The first option is certainly viable as it is "future proof" in a way by using Thunderbolt 3 docks, which will almost certainly be compatible with a new laptop when the second option inevitably comes. The cost for this future-proofing is that of the adapters for the old laptops. Taking the second option now means the obsolescence is averted for the old laptops but will come sooner for whatever replaces them. Such is life.

Answer 2

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 3

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 4

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.