Combining 5U MOTM and Synthesizers.com modules in the same cabinet

5U is a modular synthesizer format. The height of most modern modular synthesizer modules is measured by the number of vertical spaces it consumes in a standard 19" equipment rack. Modules conforming to the 5U format, for example, take up five vertical units in a 19" equipment rack. Manufacturers of 5U synthesizer modules include MOTM Synthesis Technology and Modcan.

Power Supplies 

All modules from the above manufacturers need a +/- 15v power supply. Frac modules and Wiard 300 series also use this. Some manufacturers also need a 5v source – specifically Synthesizers.com and some of the newer MOTM modules (e.g the 650 midi-CV interface)

All the manufacturers listed sell suitable power supplies.

- Synthesizers.com supplies have +/-15v and 5v - MOTM sell 2 supplies, one with only +/-15v (MOTM 900) and one which also has 5v (MOTM 950) - Cyndustries sell +/- 15v supplies - Modcan sell +/- 15v supplies

Distributing Power 

If you’ve only got one manufacturer/format then the easiest thing to do is to stick with their power supply and distribution system. Here’s what each uses:

Synthesizers.com 

Synthesizers.com use a 6 pin connector to get power from the power supply to modules.

Power is distributed from the power supply via a power harness which contains a number of these connectors. They sell 2 models: the small power harness has 20, the large has 40.

MOTM 

MOTM use a 4 pin connector on most modules – those that only need +/- 15v. These are the same power connectors that Frac and Wiard 300 series module use. Some of the newer modules, that also require 5v, use the same type of connector but with 6 pins (not the same one as Synthesizers.com use)

Power is distributed from the power supply via power distribution boards. There are two main versions – one with only 4 pin connections (i.e. +/- 15v only) and one with a mix of 4 and 6 pin connectors (so you have +/-15v and 5v)

Modcan and Cyndustries 

Modcan and Cyndustries have the same type of connector as MOTM to distribute power to modules except they only use a 3 pin version which provides +/-15v only.

Power is distributed from the power supply via a distribution board. The Modcan one (which is completely compatible with Cyndustries modules) looks like this:

But wait – I’ve got more than one 5U format!

Now it gets interesting. There is no one way to distribute power to a mix of 5U formats. Here are some off the shelf solutions.

Synthesizers.com and MOTM 

If only want to add one or two Synthesizers.com or MOTM format modules to a system mainly of the other format then Synthesizers.com sell their QMPSA adaptor which convert between the two formats. This adaptor also provides a 5v source so you can run Synthesizers.com modules off a MOTM +/-15v power supply.

For more than a couple of modules this probably isn’t the most cost effective solution though. For more modules it’s easier to use one of MOTM’s convertor boards – MOTM 995. This gives you a combination of 6 pin Synthesizers.com, 4 pin and 6 pin MOTM connectors and can be connected to either a Synthesizers.com or MOTM +/- 15v and 5v power source.

The other option is to use a Synthesizers.com power supply with a power harness to connect to the Synthesizers.com modules. You can then strip one of the 6 pin connectors off the power harness and, using the colour-coded wiring guide on the Synthesizers,com site, wire the harness directly to one of the two main MOTM power distribution boards that are pictured above – they have binding posts that make this easy to do. If you don’t need the 5v for your MOTM modules simply snip this wire short on the Synthesizers.com harness and tape it up.

Modcan/Cyndustries 

Adding Modcan and/or Cyndustries is a relatively straightforward task and in many ways you can do the same things as you do to connect Synthesizers.com and MOTM together. The only difference is that you need to account for the fact that Modcan/Cyndustries use 3 pin, rather than MOTM’s 4 pin connectors.

With Modcan probably the easiest option is to ask Bruce to terminate the power cables in MOTM style 4 pin connectors – he’s fine with doing this. You can then use exactly the same type of distribution system you’d use with a MOTM or MOTM/Synthesizers.com mix system. Remember Modcan are +/-15v only – no need to worry about 5v for them. This would also work for Cyndustries modules although I have no idea if it’s something Cynthia will do or not – can’t hurt to ask I guess!

The other option would be to use a Cyndustries power distribution board, which provides connectors for 4 pin MOTM and 3 pin Modcan/Cyndustries. This could be wired to a suitable power supply using binding posts as with the MOTM distribution boards.

STG distro board 

A further option is the distribution board made by Suit and Tie Guy. These can be ordered with a combination of Synthesizers.com, MOTM and Modcan/Cyndustries connectors. They have a set of screw terminals for attaching the power supply of your choice. Details can be found from the page in the links section below. STG can also provide suitable cables for powering Synthesizers.com modules from this distribution board. Here's a picture of one (which is now residing in my cabinet )

Links 

Modcan power information: http://www.modcan.com/bseries/bmount.html

MOTM power supply:  http://www.synthtech.com/motm900.html MOTM power distribution boards: http://www.synthtech.com/testcart/index.php?main_page=product_info&cPa th=67&products_id=180 http://www.synthtech.com/testcart/index.php?main_page=product_info&cPa th=67&products_id=182 MOTM to Synthesizers.com adaptor board: http://www.synthtech.com/testcart/index.php?main_page=product_info&cPa th=67&products_id=183

Synthesizers.com power components:  http://www.synthesizers.com/q101.html Synthesizers.com power wiring information: http://www.synthesizers.com/technical.html

Suit and Tie Guy distribution board:  http://stgsoundlabs.com/products/distro.htm Suit and Tie Guy power cable: http://stgsoundlabs.com/products/power_cable_mu.htm