Monday, April 25, 2016

Day 2 Show 1 Jazz Fest

New Orleans Jazz Fest 
It's an 'in and out' gig a bit regrettably as New Orleans is always a fun adventure of sights, sounds and delicious food.‎ I did arrive in time to hang with the Pearl Jam crew for a bit as our load in overlapped their out. It's been a while such a great camp.

It's not often I see a stage so clean, notice anything missing? 

Like the entire lighting system. New Orleans version of Warped tour, daytime shows, sunlit and work lights. Ha! In the ongoing battle with Scott the Lampi, we can rock a fun show with no lights, wonder how a lit show with no sound would go over.

Starting up a new tour cycle has its challenges. In my mind, I envision the sound setup just progressing from where it left off some two or so years ago. In reality the multitude of small and large changes converge into clusters of variables and unknowns. Plus me being rusty and the abrupt change of focus from 'at my house' to 'front of house' has me relearing all those nuances that had become second nature.

Not only was this the first show but also first time mixing on a Clair Cohesion PA as well. A variable I would have rather done without as I much prefer a familiar system, especially on the front end of a tour. The crew was good, pretty straight forward and everything functioned as it should, Ran stereo mains and stereo subs on an aux. The show was fun, especially cool ‎was the jam finale with 3 of The Meters.



Sunday, April 24, 2016

New Peppers tour show day 1

So here we go again, in New Orleans with Chili Peppers playing Jazz Fest. Trying to get my head around shifting gears from home to travel world. Rolling over the mental lists of how to approach tuning systems and all the bits not to forget to keep in my rolly bag.

4 days of rehearsals went well. I have a pretty similar setup to last tour with a few changes so far. Most exciting is a brand new console. Well not exactly but close. We had a Midas H3000 at the shop which we pulled from an installation and has lived in a theater for 15 years. Oh my those smooth slidey faders!

Also I have a pair of the new Rat Sound SuperWedges I used for my rehearsal PA. Hope to carry them as reference wedges for as much of the tour as possible.

For rehearsals I had the SuperWedges in 4-Way mode. Input 1 on the amp drives them full range 4-way with one of the 12"s 40hz-80hz and the other 12" 45hz to 300hz. This cleans up the mids and extends to lows a bit over the 3-way setting.

What is really cool is that input 2 on the amp just drives the 12" I a using a a sub and input 3 on the amp drives the other 12" plus the 10" and the 2". So I had them hooked up as stereo triamp mains plus stereo subs on an aux to recreate my real world show setup.


Well alright, off to wander about the festival an contemplate my first show mixing on the Clair Cohesion 12 system.

Monday, January 11, 2016

Subwwofer Setup for Bassnectar NYE 360 degree

In my last post I outlined the goals of the sound system design for Bassnectar's New Year Eve 360 sound setup and covered the main flown system decision and configuration (goals #1, 2 and 3). In this post I will cover the subwoofer side of things

The goals of the system design were:

  1. The sound system must be optimized for 360 degree arena coverage
  2. The system should not block sight lines or distract from the visuals in any way
  3. The system must cover the entire arena as smoothly and uniformly as possible
  4. The sub woofer must be powerful and immersive to a very low frequency
  5. The sub woofers and main system must not reproduce excessive low frequencies in the center of the room where the artist is located. (This has been a significant issue in the previous years of doing 360 degree shows before I was involved)
Achieving smooth loud low frequencies covering a large area can be quite challenging. Time alignment issues causing cancellations and huge audible holes in the coverage are quite common in all but the most well thought out configurations. To cover the venue evenly, a ring of subwoofers around the stage optimum. Unfortunately, the subwoofer sound will be the loudest at the any point that is equidistant from the most sources. With a 360 degree coverage subwoofer ring, the equidistant point is dead center and exactly where the artist is located. In past 360 coverage shows, the low frequency volume levels in the center were so loud that vision was blurred and the control equipment needed to be strapped down to prevent it from rattling, falling and there were issues with hard drive malfunctions.

Here is a coverage map of a ring of subwoofers 38 feet in diameter. The grid lines are spaced at 50 feet. In the prediction below with a single ring of 8 clusters of 5 subs, 40 total, we are able to get 103 db at 300 feet away where I marked the level. The prediction specs are listed on the left side of the image measured 20 to 80hz. The actual venue is much smaller so the actual levels were much higher for even the farthest audience member.


But, now lets look at the level in the center where Lorin will be DJ'ing from::


Yikes! 134 db is crazy loud and over 30 db louder than the sound 300 feet away. So, the challenge is to reduce the level in the middle significantly and also if we can get more level far away, that would great. Additionally the solution should look cool and be physically feasible to achieve without disrupting the super smooth coverage we already show.

So to do this I added an inner ring of subs that were also facing outward. the inner sub has a diameter 14 feet smaller and is 8 clusters of 3 subs totaling 24. 


The reason clusters of 3 were chosen rather than more or less was that an inner ring of 24 generated a volume level dead center that most closely matched the volume level that the outer ring generated dead center. The idea is to have both cluster create as close to identical signals dead center as possible. 


The reason a spacing of 7 feet was chosen is that 7 feet is 1/4 wavelength at 40 hz, which is the center frequency between the 20 and 80 hz.and the frequency I wanted to optimize for. For more info on setting up sub arrays I have 3 youtube videos on sub setups:




Ok, so since the most critical purpose of this sub setup is to drastically reduce the level in the center I used a polarity reversed cardioid setup. Once the volume levels are matched as close as possible measuring from room center, then the arrival times of from both the inner and outer subs are matched as well. For this setup at 25 degree C and a spacing of 7 feet, it required the inner ring to be delayed 6.2 ms for maximum summation room center. Then I inverted the polarity of the inner rings and rather than maximum summation, maximum cancellation was achieved. Here are the predictions with the inner ring:


Ok, that's good, we gained a few db at 300 feet, the prediction still shows smooth coverage all the way around so lets look at the level in the middle.


Awesome! 93 db in the middle and  over 10 db quieter than the 105+ db level at 300 feet away. Super cool and exactly what I was looking for. Of course there was a lot of messing around to get to this point. Paul F at Rat helped me with some skills using soundvision software, which I am not overly well versed at. Also Jason Brandt not only assisted in refining the predictions, he also was invaluable in implementing the setup and getting it to perform as predicted. 


And an up close


The real world outcome was quite interesting. The subs covered quite well throughout. No significant holes, low end naturally drops with distance but we were able to get a pretty good level to the rafters. When walking to the center, the low end became oddly decentralized between the rings and when you got up into the central booth, you could feel low end and hear the rotating structure rattling but the it sounded distant and there was an almost surreal drop in level.

If all that info is not enough for you or you are versed in Soundvision software, here a link to download the file with all the info:


And here a link to download Soundvision, though you probably will need a training course to use it.


Cool cool, hope this is interesting stuff, hit me up with comments on stuff you like or want more of.  Gonna try and get back into the rhythm of posting and sharing.

DR 

Thursday, January 7, 2016

Designing a 360 sound setup for Bassnectar

Over the past year I have been working on and off with Bassnectar as a sound consultant. My position is multifaceted and in general I work to solve some technical challenges so Lorin (Bassnectar) can achieve the audio connection with the audience he is looking for. My focus has been on improving the audio impact of the show when there are overly restrictive sound limitations, occasionally I fill in as the sound engineer if Jason Decter is not available and I also work with Jason and production on the design of the sound system when Bassnectar is bringing in full production.

I really enjoy working with Lorin, Jason and the full production team. Not unlike working with Chili Peppers, Lorin and the whole team really care about all aspects of his shows. For this past New Years Eve show I was brought in to design a sound system with some unique and fun challenges.

The first step was outline the goals:
  1. The sound system must be optimized for 360 degree arena coverage
  2. The system should not block sight lines or distract from the visuals in any way
  3. The system must cover the entire arena as smoothly and uniformly as possible
  4. The sub woofer must be powerful and immersive to a very low frequency
  5. The sub woofers and main system must not reproduce excessive low frequencies in the center of the room where the artist is located. (This has been a significant issue in the previous years of doing 360 degree shows before I was involved)
Achieving 360 degree coverage from a conventional line array system is not overly challenging if one is willing to hang 5 or more clusters. The problem is that one can not physically put two line array hangs next to each other without a space between them if they are not both pointed in the same direction.due to the "J" shape of a conventional line array.


Additionally, placing J shaped line arrays in close proximity will cause undesirable interference if the same signal is sent to to both arrays. To deal with the interference, the arrays need to be physically separated.


But regardless of whether they are closely placed or separated, the amount of sight line blockage of video screens can be an issue.

For this particulate show, the video screens in the arena scoreboard were incorporated as a central video source which meant that if I could place sound arrays at the 4 corners of the square scoreboard, I could minimize sight line blockage, yet to cover the venue sound wise each of the 4 sound arrays would need a relatively wide coverage and would need to be flown in a relatively limited vertical space.

To solve this challenge analyzed and compared coverage, volume levels and sight lines using a conventional J shaped Line array versus using an EAW ANYA system. The EAW ANYA system offers some unique advantages for this application in that the arrays hang in a straight line rather than a J shape. Additionally 2 or more arrays can be connected together side by side, increasing the horizontal coverage while minimizing blocking the video screens and lighting. Additionally, since the vertical coverage of the ANYA system is controlled electronically, the trim height of the sound system could be adjusted to an optimal height without compromising coverage. Here is the ANYA system layout with the goal of exceed 105 A weighted throughout the venue


And here is the system in the actual show during setup


And a closer pic of one of the arrays


And tweeted pic of the full show


In this application, it is all about sound being heard and not seen and an enjoyable challenge working with video, lights, riggers and all of production to merge everything together.

And as predicted, the system was able to meet meet the first 3 goals. In my next post I will discuss how goals #4 and #5 which involved the subwoofers challenges, were addressed.

Cool cool, and never forget to have fun making it loud!

DR