Multi-Console Setups for Concerts

I remember a college assignment where I had to design a sound reinforcement system with a multiple console setup for a stadium sized venue and I was quite stumped as to how the whole thing was done at that point. After much research, asking around and reading about it I managed to gain a basic understanding of the entire signal flow, now about 5 years on I have seen most of these setups and done quite a few shows with such setups. Here is my understanding of the signal flow and setup of MOH and FOH both analog and digital.

Stage Setup

From the point of view of stage, not much changes except that all the inputs which would get patched into the console snake now get patched to a Splitter. The splitter takes in a single input and gives out multiple transformer isolated balanced outputs(“copies”) of the signal for use with monitor consoles, broadcast OB van consoles, recording outputs etc. Most commonly splitters give out two splits, one for the Front of House (FOH)) console and another for the Monitors On House (MOH) console.

As seen in the picture on the right the inputs get patched as standard into the snake however there are two outputs of the signal given out, one called the Main and the other called the Split output. The difference between both is that only the main output allows passing of phantom power from the console to the mic. If both splits were allowed to pass phantom power that would lead to two separate feeds of +48V(dc) adding upto +96V(dc) which would cause your mic to get fried for sure!

Whirlwind concert system   Generally the main out is given to the console with priority such as FOH console which mixes for the audience and the split out is given to the lesser priority consoles such as the MOH, or Broadcast etc. When a mic needs phantom power it is upon the FOH engineer to turn on the phantom power so that the MOH engineer also receives the mic signal.

Various other splitters such as the DS-800 by XTA Electronics allow upto 4 separate splits of the signal with transformer isolation as a fixed feature. However due to the higher number of splits each unit only takes in about 8 inputs, which means for a 55 input situation there would be a requirement of about 7 DS-800’s which is as expensive as a console!

Front Of House(FOH)

The FOH console would receive the first split from the splitter which would mean that phantom power requirement are to be met from the person operating this console. Not significant changes happen when it comes to the mixing procedure since analog splits allow consoles at MOH and FOH to work independently.

Monitor Of House(MOH)

The MOH console receives the second split out from the splitter and will depend on the FOH operator only for phantom power to be turned on for condenser mics, in all other cases MOH operation is entirely independent from FOH.

Communication Between MOH and FOH

Since there are some discussions about the weather and about the neighbours dog that need to take place between FOH and MOH a communication medium is required between both the consoles. The good old way of screaming your guts out over the PA might work in small venues but in a stadium with a monstrous PA it might be quite futile. Cellphones are another common medium but may not be useful if you are doing a show on some beachside in the middle of timbuktu, cellphone networks may not be reliable, as for walky talkies lets not even get to those since they never work as expected, unless you bring your own set.

The best way to work for communication is usage of the good ol’ talkback mic being routed out from the console and being returned through the stage snake and fed to the monitor console as an input and a similar thing done by the monitor console operator. My preference has always been to send it through the direct out on the channel of talkback and the talkback coming from the other console can be directly routed to the console wedges for uninterrupted communication. Some people prefer their talkback being sent through an aux for some reason that i can’t comprehend…maybe its an analog habit.

The digital side of things

Digital setups allow usage of the console stage box to be used as a splitter and allow separate feeds for MOH and FOH without having to run the bulky Concert Snake and another snake for returns. One single fiber-optic or BNC line can carry upto 96 channels of digital audio with control data and the without any significant noise interference. Most of these stage boxes from leading manufacturers such as Midas, Digico, Soundcraft, Avid, offer a split option on the stage box where u can connect another snake and get a split of the signal. The rest remains similar, i.e. the FOH console controls the preamps on the stagebox. So if the FOH operator increases gain on a certain channel the Monitor console signal will be increased by the same amount.digital stagebox

This may seem quite stupid but is the way digital works. This would of course create havoc for the monitor engineer as changing gain levels during show results in monitor mix changes and brings on the wrath of the egoistic artist. Most consoles to counter this have created an option called trim which is the next knob after the gain, which allows you to compensate for such changes. I don’t if the other consoles do it automatically but Digico allows automatic compensation of the gain level. Midas on the other hand i think offers independent feeds but I can’t be quite sure about that.

Hope this was informative and clear.Here is an image that will sum it all up from the analog point of view. Thanks for reading. If you liked this article please do recommend it to your friends and share the word.

MOH_FOH signal flow

Studio One 2 Free Version released.

Presonus marketing team is seriously killing the competition right now with the release of Studio One 2 Free. As soon as I read the word “free”, I immediately downloaded it without hesitation since I was a fan of their software from the very beginning. And over the past few days I tried out this version,  which I feel is gonna  be a Godsend for individuals, project studios with no software budget, and students.

Download Link Studio One 2 Free

Without trying to waste too much time, I’ll just give u the features that are the USP(Unique selling Proposition) of Studio One 2 Free.

  • Unlimited audio, midi, automation tracks.(that’s all I needed to read).
  • The same sound engine from Studio One 2 Pro versions.
  • Great user interface and rock solid stable.
  • Full hardware support for most common midi/audio devices.
  • Export individual tracks, stereo mixdown or stems (yes stems!) to Wave or Ogg Vorbis.
  • Free version of Presence, a virtual instrument with 323 MB of free content.
  • Support for Presonus Studiolive Mixers hence perfect for live recordings.
  • 8 Basic effects such as Delay, Chorus, Flanger, Reverb, EQ, Dynamics and Distortion Unit.
  • Did I mention its free 🙂

What you don’t get in this version is summed up right here

  • Melodyne.
  • Folder tracks.
  • Transient detection.
  • The huge effects library. (we are limited to 8 basic effects for the free version)
  • No  VST/AU/ReWire support. (I wish they had a limit rather than no support)
  • No mastering suite.
  • No Quicktime video support.
  • No export to MP3.

That mostly sums it up, just hit the download link and enter your email id, download the installer file and run it. The first time you run the application, just hit free version in the opening window, and voila you have your own DAW for a price of $0. Thanks to the guys at Presonus for the great piece of software, I hope more people see the benefits and upgrade to the pro versions.

Download Link Studio One 2 Free

Studio one DAw

Multitracks for Mixing

During my early years in audio, i used to look around the internet for multitracks to practice my mixing skills but most of the available ones were quite bad quality and the good ones were too expensive. My search finally led me to this website which was hidden away in one corner of the internet. For those of you who read SoundOnSound magazine will remember “Mix Rescue” sections where they showed how they managed to make a terrible recording sound amazing. Here are some of the multitracks from that section of the magazine made available by one of the contributing authors for personal and educational use. Do have fun mixing these tracks, some of them are quite amazing.

Multi-tracks for Mixing

You can also find this same link on my downloads page, incase u need it at any later point.

No Copyright Infringement Intended. “Copyright Disclaimer Under Section 107 of the Copyright Act 1976, allowance is made for “fair use” for purposes such as criticism, comment, news reporting, teaching, scholarship, and research. Fair use is a use permitted by copyright statute that might otherwise be infringing. Non-profit, educational or personal use tips the balance in favor of fair use

Audio Frequency Chart.

Just received this chart from my Alma mater(SAE, Singapore) and thought that it was worth sharing. This chart shows frequency ranges of most common instruments including the harmonic ranges. At the same time it gives word descriptions for various frequency ranges such as “depth”, “impact” etc which can be useful to understand what frequencies correspond to such descriptions. To download right-click and hit “Save as”. 

Audio Myth or Fact?

I was just sitting and watching this video tutorial by Dave rat(http://www.daverat.com/) evaluating some audio myth about headphones sounding better after being “burnt in”. At the end of the video he found no measurable difference between before and after results. This led me to think about the various “myths” I’ve heard such as mics sounding better after being dropped (heard it from a SAE classmate in singapore..sorry mont!:P) , gold-plated connectors are better than tin or nickel, NS-10m Speakers sound better than anything else on earth (this myth is making some Vietnamese people really rich..:P). I could go on for days with the ones i’ve heard and if you wanna hear some more just goto gearslutz..:).

And i think this is not just a problem in audio, but rather in every field of media. The internet while being a wonderful resource has just helped in raising more myths than squashing them, since every tom(sorry tom!) out there with a computer writes his own stuff which is read by some gullible person and then we hear these myths around. While I’m not out to take on each of these myths individually, i think SOS(http://www.soundonsound.com/) and many more credible sources are doing a way better job at it, i just wanted to share my approach to tackling a situation when i hear something that seems like a myth. Get your Mythbusters hats on!

The three most important things i consider for audio myths to be considered authentic are the following

1. A myth has to be logical

If it doesn’t make sense how will it work? if it doesn’t have a logic behind it chances are most probably it is a myth. Though this is just one aspect of understanding a myth it is an important one. If the logic behind a myth seems a little shaky it probably because someone made it up or didn’t research it right. However if it is logical doesn’t prove much unless the other two considerations are fulfilled.

2. A myth has to be measurable

The great thing about being in this century is that with the present technology quantities in audio that could only be heard can now be measured.Using oscilloscopes, high-resolution RTA’s, Voltmeters etc many audio quantities can be measured. So if there is indeed a

audio measurement oscillator

measurable quantity that proves the myth, it can be accepted. However measurements only show relative differences which cannot be necessarily described as improvements. I have faced this scenario often when many of my engineer friends look at some hi-fi audio gear frequency response curves and then compare it to professional gear. Both curves may look the same(Photoshop!), but may not really sound the same.

3. A myth has to be audible

If 24/192 makes so much of a difference than 24/96, it should be audible to more people than just Rupert Neve!(that brings me to another myth http://www.jhamptone.com/tag/geoff-emerick/). In the audio world its all about hearing it, if u can’t hear it its probably not making all that amount of difference. Right now there are about a dozen companies that sell a copy of the Rupert Neve 1073 mic preamp with supposedly the “same” sound for half the price. Do they both sound the same? i haven’t heard either but i hope they don’t..

I hope I came across a little bit clearly on these three aspects that are needed to evaluate such audio myths though they aren’t restricted to audio mythbusting but can be used in any field. Also I would like to emphasize that audio engineers should be very selective about believing their information resources. Hope this was informative. Don’t believe everything you read on the internet or hear from your colleagues!

Thanks for reading. Big shout out to Lazarus (http://clickamillions.com/), do go to his website he has some amazing photography tutorials there especially the ones on HDR photography.