A SMALL MIDI TOOL!

A midi merge box

• Current synthesizers are now often equipped with software allowing their setting from a PC / MAC.
• For those who prefer hardware sound generators rather than software, the number of machines to be controlled tends to increase over the years.
• The topology of the MIDI network is not efficient when it is necessary to connect several MIDI out to a single MIDI in.
• Several solutions are available to overcome this problem but often it does not work well but still costs a 'certain' price.

In order to meet all these challenges, a few years ago I bought a USB / MIDI interface with 8 MIDI IN / OUT ports. Unfortunately, the management of MIDI information passing from external machines to the PC / MAC was buggy. Only 16 bytes were correctly treated. Longer messages were not transmitted correctly. Impossible then to download a complete set of patches.

Since I'm tired of buying unreliable devices, I decided to create my own very simple interface:

This interface is passive. That is to say that it does not control the MIDI packets arriving on the inputs to transmit them on the single output. 

This implies a single operating constraint: a single external device must send data at a given time to this interface. If the connected devices don't emit anything until you ask them to, that's okay. 

If a device continuously emits real-time information for example, and it is impossible to prevent it to do that, it is sufficient to easily disconnect it from the box, using the corresponding switch.

And the MIDI DIN5 sockets... I hate them. So I installed 3.5mm jacks for easier handling. It will obviously be necessary to make suitable cables but it is easy to do.