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0:00 - Introduction
1:50 - Do I need a patch bay?
2:40 - What does a patch bay do?
4:09 - Types of patch bay
6:18 - Organising the patch bay
14:08 - Grounding and mains hum buzz
17:10 - Plan the patch bay
19:40 - Preparing to solder
21:25 - How to solder
26:08 - Conclusion

So What is a Patch Bay?
A patch bay is a way of easily connecting together the bits of gear in your studio.

Everything in the studio is plugged into the patch bay. With the use of small patch cables you are able to connect one piece of equipment to another just using the patch bay. This negates any annoying escapades around the back of the equipment plugging and unplugging things where you can’t see anything.

Do I Need a Patch Bay?
Possibly not! If you don’t have any outboard gear then definitely not but if you have a lot of items that you want to connect in different configurations then it’s well worth thinking about!

Mixers, compressors, gates, other processors, audio interfaces, mic preamps, keyboards, reverb and FX units as well as various other units can be connected together ad-hoc and at will.

It’s a fair bit of work to set it all up but there’s a great sense of achievement after soldering your own patch bay.

Where Can I Get One?
I got mine from ebay. I had to clean it up but it was easy to do and took about an hour. Ideally you want soldered connections as this will give you the cleanest signal (assuming your soldering is decent enough!)

Digital patch bays are an option too…they are expensive but totally rad. You save the patching configuration in the computer and it’s automatically recalled each time you open the relevant project.

How Do I Connect a Patch Bay?
Hold your horses! There’s a few things to know about how to set up a patch bay and how to lay it out to suit a particular studio and workflow.

I’m Not Normal.
Normalling (not normalising) is an important concept in the patch bay. This is best explained with an example:

In my studio I’d like my SSL Fusion permanently fed by output 3-4 on the audio interface. In turn, the outputs of the SSL Fusion I would like to be permanently routed to inputs 3-4. This gives me the easy option of feeding any source through the SSL Fusion at will using Logic’s I/O plugin. Great.

Normalled routing
This is where normalling comes in. We can normal these connections on the patch bay. This means that even without any patch cables used these connections will be made.

More Than Half-Normal
There are a few different types of normalling. The convention on a patch bay is to have the outputs at the top and the inputs at the bottom.

Types of normalling
Full normalling
Means that when you plug into either the input or the output it will break the signal flow between the two.

Half normalling
Will only break the connection when we plug into the input but not when we plug into the output. This means you can use the patch bay as a kind of splitter and divert the output off to somewhere else while still keeping the normalled connection.

Thru
Thru means there is no normalling and a connection will only be made when a patch cable is inserted.

Ground Loops, Mains Hum and Earths.
A ground loop is the annoying buzzing sound you sometimes get with audio gear. It happens when there is more than one path to earth.

The electrons would ordinarily make their way to earth in an orderly fashion but, if there are two paths to earth they can get confused! This will produce awful buzzing sound as they push and shove one another, looking for the the best exit!

This really is a terrible shame! This buzz will end up all over your recordings as well as being irritating in the first place.

Generally it is because two pieces of audio gear are connected together with a cable that contains an earth. This is shown below.

Ground Loop
As each piece of gear is earthed via a mains plug, any point in the cable or circuitry has two paths two earth. The red dot in the diagram below indicates an electron and its path to earth.

Remove mains hum
The simple way out of this is to break the earth at some point so that at any one point there is only a single path to earth:

Stop buzzing by removing earth loop
This patch bay actually was set up for that already. The input side only has two solder points, the earth has been left out and only the hot and cold are connected. The blue line above shows where the earth loop is cut.

All that remains is to neatly cut back and insulate the earth so it doesn’t inadvertently touch anything else.