Patchbays For A Home Studio
After sharing some photographs of upgrades I’ve made to my home studio, I received a few private messages from people who asked how I set various devices up. Thinking about it, I think it would be a good idea to start a blogging feature for the website to explain and share such things and get feedback.
To explain my current layout, I feel I really need to explain the layout I had before and the needs I had that led me towards a mixer-less patchbay configuration. I’ll describe my previous setup and its inherent limitations, the technology breakthroughs that made me reconsider a patchbay oriented environment, and the method I used to configure and wire my patchbays.
The Cheap But Manageable Old System
If you’ve followed my posts for the last couple of years, you’ll know that I’ve started to utilize more and more outboard gear in my audio production while maintaining what I feel are the core benefits of ITB (inside-the-box) audio production. The decision to go forward with the home studio patchbay project is tied directly to the concepts of outisde the box and inside the box audio production.
The advent of “prosumer” super low latency audio interfaces is really pushing the boundaries of the value one can squeeze out of a home music studio on a budget. Previously, audio interfaces not in the pro market ran on connection interfaces on the computer using formats such as USB or Firewire, opposed to the PCIe interfaces with much lower levels of latency in the pro market. While these USB and Fireware devices made it easy for one to easily record multiple streams of audio and sequence audio playback, they did so at the cost of the medium sacrificing latency. The latency derived from the amount of time it took audio to traverse the computer software and hardware bus. While you were spending a fraction of the cost of say a top of the line Avid HDX system with PCIe interface and DSP processing, you had to deal with the fact that realtime audio manipulation would incur much latency in the process if you ever planned to send audio in and out of your computer for further processing.
The majority of people using these USB and Firewire devices, if they lived entirely ITB, were for the most part unaffected by this. At most, they would need to adjust their audio buffer higher if they had many plugins running at once, but other than that it was painless.
Some people however have lots of outboard gear traditionally made for OTB (outside-the-box) environments or pro low latency environments with plentiful i/o ports. As I’m writing this, it is currently 2019 and I have a plethora of outboard audio equipment. Synthesizers, distortion units, compressors, limiters, filters, reverbs, delays, samplers, you name it and it’s here.
Previously on USB and Firewire devices I could get by using a pair of in and out ports and capture the channel’s wet return. On some outboard devices the aforementioned latency causes no real issues. Compressors and distortion effects notably. However, doing so with reverb and delay units always introduced a consistent albeit lofi charmingly annoying delay on the recorded return. When recording instruments such as guitar, synthesizer, samplers, drums, and vocals, one frequently needed to determine the amount of samples the recorded was offset and correct it.
At the time I believed the best way to squeeze the value out of my gear was to record with a mixer as a front end to my audio interface as well as to manage insert and aux effects. I never had any intention of mixing on my 32-channel Behringer SX3242FX, I just needed a wide variety of channels available while composing. When I needed to process something already recorded it was easily enough to run it back through the mixer, to the effects devices or via the aux channels, and rerecord the colored return. This worked out fairly well for some time, but really limited 1) by the amount of chains you go in and out and 2) by the time it took to wire everything up into the correct insert or aux ports.
There were times where I was discouraged from having to make the routes through the mixer as it was an ardous process. When I gave into that discouragement I also begin to hear where I was missing that fun outboard processing happy accident quality that one gets physically playing with knobs away from a computer screen. As time went on I squeezed the best of both worlds as best as I could knowing I wasn’t getting the full benefits of my outboard gear due to the limitations of the technology that came burdened with latency in exchange for its affordable price tag.
And then the most wonderful two things in a long time happened to the music production industry: 1) Apple and Intel pioneered the Thunderbolt spec, a USB-like direct PCIe connection via cable and 2) Vendors started shipping Thunderbolt-enabled interfaces specifically tailored to take advantage of the increased bandwidth and speed that Thunderbolt provided.
At first, it wasn’t great. The few vendors who shipped initial offerings simply re-used their existing USB based designs with a Thunderbolt connector, with the chipsets effectively using Thunderbolt as a USB hub wrapper. The result was no real benefit other than bandwidth of audio.
When proper Thunderbolt audio interfaces started to hit the market, however, it was like a kick of lightning. Many vendors have them in place these days, and the one I chose to go with was the Presonus Quantum. This audio interfaces is a beast and I’ve been able to get HDX levels of low-latency audio out of it for a fraction of the cost. Supporting 8 channels in / 8 channels out, and optional 16 channels in / 16 channels out via ADAT/lightpipe, it is a fully native Thunderbolt 2 interface with all the speed you expect from a super fast PCIe port and with all of the ease of use of a USB device.
It no longer made sense to utilize my mixer as a front end interface for all of my outboard equipment when this cheaply priced Quantum could handle those connections natively and with more routing possibilities. In most DAWs you can easily set up outboard equipment and use it either on a bus or like a plugin. I was able to test up to 10 loops back and forth in this manner with a combined latency of no more than 12ms which was incredible. For a single one, it goes down closer to 2-3ms. The roundtrip tests made me quicly realize I needed to be able to quickly patch my devices in arbitrary configurations per session to get the most out of my outboard gear.
Enter The Patchbays
Patchbays are as old as audio recording, or very nearly there. In essense, the purpose of a patchbay is to provide a front end in physical form for instruments, audio signal processors, audio inputs and audio outputs. Traditionally, patchbays are configured uniformly where outputs are on the top row and inputs are on the bottom. All your gear plugins into the back of them leaving you only having to use a smaller patch cable in the front to patch maybe a synth from one output, to a compressor, and then to a distortion pedal, and then to an in on your audio interface all without having to go behind your ever growing cabinet of gear and cable mess behind your desk. No more managing cables directly from one device to another, just wire the path together on the front of the patchbay and you’re good to go!
Normal, Half-Normal, and Thru
There are usually 3 main modes that port sets on a patchbay can be configured as: normal, half-normal, and thru.
Before purchasing all the equipment I needed to set up the patchbay, I re-read up on the terms and methods used to make sure I would have everything I needed. For the most part, people usually tend to use a patchbay in half-normal mode, although in your home studio you can do really whatever you want because few people will ever use your studio the way you do.
With the different types of devices in play, I split my gear into 3 categories: 1) instruments, 2) effects units, and 3) audio interface I/O ports. From there it became more clear how I was going to configure my patchbays.
Instruments – When thinking of most instruments, the vast majority of them are going to have outputs exclusively. Because you’re effectively not worried about input, THRU mode on a patchbay would work well because you can effectively use the top and bottom ports of the patchbay independently of each other. If you have a 48 port patchbay, you’ll be able to fit 48 instrument outputs in THRU mode if you set each port set to THRU.
Effects Units – You really have a choice here, however I chose to go with HALF-NORMAL mode. The outputs of my effects units went on top, and the inputs went on bottom. Think of it like a waterfall, the audio comes out from the top and falls down. If you have a 48 port patchbay, you’ll be able to fit 24 effect unit input and outputs in both HALF-NORMAL and NORMAL modes.
Audio Interface I/O – Unlike Instruments, we are dealing with both inputs and outputs with this category, however unlike effects units in which the audio signal is purposefully linked between the output of a device and its in during the signal flow, you definitely want audio interfaces inputs and outputs to function independently of one another. For this reason, I chose to go with THRU mode on all 24 inputs and outputs my Presonus Quantum and two Behringer ADA8200 channel strips afforded me. I keep the same layout, with all of my outputs on top and all of my inputs on the bottom. In the DAW, I can send anything from a previously recorded piece of audio to a live virtual instruments out through my patchbay, to effects units, and back to an input port, all without getting out of my chair.
You can wire your studio up any way you please, there’s no one right way, although there are definent wrong ways. Experiment and ask others. If you have a Thunderbolt interface and want to experiment with outboard gear, I suggest to start small. Back in the day I started with guitar pedals I had lying around. There’s something really great about outboard gear that plugins have never captured for me, although plugins certainly have their place in my home studio along with ITB mixing capabilities.
And you aren’t limited to my setup. The people I talked with about this project beforehand told me about all sorts of fun things they were doing. In addition to the things I ended up adopting, they were able to easily run audio outs from the patchbay to their mixers so they could mix OTB. This brings up a good distinction between the method I’ve adopted and pure OTB mixing: while I’m using outboard gear, I’m effectly using them to color audio as I record it, or as plugin/route wrappers routing hardware signals, that only works as well as it does because of the super low latency Presonus Quantum. But wiring up my patchbay as I did, I can mix OTB if I wanted to with 1-24 TRS cables, or do half and half splitting up outputs between effects routing and outputs to a mixer.
The benefit is clear though: my back won’t hurt nearly as much constantly jumping behind my racks and wiring things together by hand. That’s worth its weight in gold for me.