Archive for July, 2009
Unwritten Rules of Mixing Monitors Part 1
I came across a cool thread recently on one of the discussion forums about the unwritten rules for mixing monitors that they don’t teach you at Full Sail (I added that last part!). This is all the kinds of things I think many of us take for granted but will take a growing engineer up several levels by mastering. Part 1 today, part 2 on Monday. Credit goes to everyone who contributed to the thread!
- Never put anything in someone’s wedge mix they didnt ask for.
- Never change a mix after the third song, unless its a ballad or something rehearsed in soundcheck.
- The best soundcheck adjustment can be moving a monitor slightly or changing the angle using a short 2×4.
- Know what your wedges and IEM’s sound like. Know what wedges sound like solo, in pairs, and with and without the foh rig on.
- Every stage is different but low end and especially low mids build up fast with 6 or 8 wedges all blasting away. Once you start adding a vocal to 2 or 3 different mixes you may have to start dialing back more low end than you did when you tuned one wedge with one vocal in it.
- Be responsive. Sometimes on crowded stages this is hard to do when every musician seems to have wishes at once.
- Don’t rely on your cue wedge all the time. Listen on stage whenever you can during soundcheck time so you can hear the actual mix, wegde and stagenoise combined on the musicians spot.
- When the stage is loud and the singer wants more of his/her vocal in the wedge, and you’ve reached the point where this can’t be easily done, you can often subtract competing instruments/vocal from the mix and solve the problem.
- Unless it is specified on a rider, number your mixes from downstage to upstage, and from stage right to stage left. This is consistent with how you would see it from FOH. It should also match the way vocals are typically laid out too. It doesn’t matter which side of the stage you are on, keep the mixes the same way. Usually the drum mix is the last mix in line. A typical 4 piece band would be like this. Downstage right is mix 1. Center vocal is mix 2. Downstage left is mix 3. Drums are mix 4. You will find that this numbering scheme has become a de facto standard in the SR world and engineers and bands alike will appreciate the consistency.
- Take care of your ears. The stage is a very, very loud place to be. Add in the fact that you have to listen to a cue wedge at pretty extreme volumes to get over the stage wash only makes it worse. I usually mix 2-3 songs off the wedge, then pop in my ear buds and use the headphone out on the console. This really helps you prevent ear fatigue, and it actually lets you here those tiny squeeks a little easier.
What are yours? Add them in the comments section.
One last hurrah for the 650s
The last weekend on the KF650s had some extra drama. Only fitting, I guess.
For some reason I didn’t turn on the PA when I first arrived to prep for Saturday afternoon rehearsal. Normally I set up iTunes with some music while we work, but this day silence seemed like a better idea. Once the stage was set, I turned on the PA but we still didn’t put music through. Sitting at FOH programming the console for the day, I heard a strange pop come from the stage. It seemed like it might be from the PA but everything was still muted and I’d never heard a sound like this before. A few minutes later, it happened again but this time I was looking at the signal meters of the desk and didn’t see a blip. This time I became concerned that there might be a problem downstream of the desk and we went into troubleshooting mode.
Some iTunes music through the system revealed that the mid and low channels of the right side our tri-amp’d KF650s were not functioning. A visual inspection of the Macrotech 5002 amps showed that both the mid and low channel signal lights were remaining on, in IOC mode, but obviously not passing signal. After power cycling a time or two, we realized each amp would pass signal for 5 seconds or so and then set into the IOC mode.
At this point, we were less than 45 minutes away from the band arriving and trying to figure out how to salvage the weekend. Thankfully, God provided exactly what we needed. Kensington has an old Turbosound rig that we call our “Yellow Truck” system because it used to be the primary portable rig for off-site ministry events. Thankfully, the amp rack for that rig, which just so happens to include 2 Macrotech 3600 amps, was on site and 30 minutes later was patched in place of the 5002s having trouble. Catastrophe averted.
I’m not sure what lessons there are to learn from this. It is a total fluke that I didn’t run music earlier in the day as I normally would. If I had, we would have had twice as much time to come up with a solution. It seems the biggest reminder is to make sure backup plans are in place for as many components of your system as possible. What would you do if drivers were to blow during rehearsal/service, amplifiers don’t function, wireless microphones fail, etc? Anything can happen and the most important thing is to be prepared to adjust and keep the “show’ going.
I guess our good ol’ KF650s didn’t want to go out without a bang!
Some new diggs
If you follow this blog via RSS reader, which Google Analytics says most readers do, you might have missed a facelift that recently went live at www.cordernotes.com. Besides an aesthetic update, there’s some new and updated page content.
My favorite addition: thanks to a nifty feature in Google Reader where you can create public blogrolls, I’ve assembled a dynamic page of links to sites related to audio, church audio, production, industry news, etc that I follow every day in GR. I’m interested what other great resources or reads I might be missing. Add other sites that are must read in the comments to this post and I’ll add them to the list.
This site is still completely hosted using WordPress. I remain so impressed by the UI for WordPress on my server, the solid tools for writing and posting content, and the ability to completely administer the site remotely from my iPhone. I have recently experimented with some other options out there for a site like this and remain convinced that WordPress is the way to go.
Check it out! We’ll return to your regularly scheduled posts on Wednesday.
d&b DSP and amplifier plan
To wrap up this mini-series on the new d&b rig (if you missed any posts, be sure to go back through the past three for more info on what is going on), today’s post will focus on DSP & amplifiers.
On our old KF650 rig, DSP was extremely important. We used a BSS London BLU-80 to provide an insane amount of processing to the entire rig, essentially trying to polish it to a point of usability.
When we decided on going with d&b, a significant bonus to the system is the awesome amplifiers with built-in DSP for system processing. While some manufacturers lock down almost all system settings making it too difficult to customize the rig to the room, d&b has done a great job of creating a system with what I believe to be just the right amount of control to tune the room. Because of this, my goal was to have as little DSP as necessary to make the rig sound good.
Our signal chain now is a left/right feed from the console that hits the first system amplifier, then simply loops through to each of the other amps. The system is run full range from the console rather than aux fed subs so that the phase and spectral response of the PA as a whole will remain consistent from service to service and engineer to engineer.
Each amplifier channel has a 4 band fully parametric EQ & signal delay. The coolest part of the DSP, though, is a few other settings available that provide subtle ways to sculpt the rig artistically for different responses depending on what’s desired.
- The CPL (Coupling) circuit compensates for coupling effects between the cabinets. These effects increase as the length of the line array is extended. CPL begins gradually at 1 kHz, with the maximum attenuation below 400 Hz, providing a balanced frequency response when T10 cabinets are used in arrays of four or more. The function of the CPL circuit in these amplifiers can be set in dB attenuation values between –9 and 0, or a positive CPL value which creates an adjustable low frequency boost around 65 Hz (0 to +5 dB).
- The HFC (High Frequency Compensation) circuit compensates for loss of high frequency energy due to absorption in air when loudspeakers are used to cover far field listening positions. It’s almost like an “air” control that gives a few options for how open the high end responds.
The D6 and D12 amplifiers have three configurations for T10 cabinets, Line, Arc and PS (point source). The Line or Arc configurations are selected when the T10 loudspeaker is used as a line array. The chosen configuration will depend on the curvature of the array. The Line configuration is selected when groups of four or more T10 cabinets are coupled in a straight long throw array section, where the splay angles to adjacent cabinets are 0° to 2°. The Arc configuration is selected when T10 cabinets are used in curved array sections, where the splay angles to adjacent cabinets are 3° or more. Within a typical array both amplifier configurations are used. The PS configuration is selected when the T10 is used as a single spherical loudspeaker.
Wrapping up this section on DSP and amplifier control, I’m very impressed by the R1 software included with the amplifiers to provide remote control from FOH of the entire rig. Tuning functions such as EQ, delay, HFC, and CPL are all included, but the coolest function to me is a page we set up that shows the input level into the amps, the output level the amps are actually sending so you can visually see your system headroom, actual ohm loads on the amps, actual RMS output wattage, power supply voltage, gain reduction, and temperature warnings. The software is completely customizable so you can set up pages to show exactly what you want, how you would best like the information. Great stuff!
d&b subwoofer placement
Continuing this mini-series on our new PA at Kensington Troy, today we’re going to talk about subwoofers. This post might be a bit premature since we have not settled on the final quantity and location of the B2 subwoofers that provide the bottom end of the rig.
I must say, these subs have always been some of my favorite. They are very very tight and punchy, with what feels like headroom for days. Some subwoofers start to break up when pushed and “feel” like they’re being pushed. These B2s can run right up to the brink and actually sound better as they’re doing it. The result is a rig that feels like it has no limits! Pretty awesome to mix on, I must say! :)
From the ArrayCalc software, here is the predicted pattern of our initial configuration – 2 subs equally spaced on the stage deck approximately 40 feet apart.
This looks a little nastier on paper then it actually feels in context, but there is definitely some slight banding of the low end in this configuration. Another option that I think I want to try is 3 subs in a cardiod configuration flown over the center downstage position where our old center cluster used to live. Here’s its predicted response…
As you can see, there’s a big difference in how these two configurations will perform in the room. The jury is still out on which direction we will go. I’m hoping to try this soon with the boxes on the stage deck before we commit to the air and see how it translates compared to the equally spaced approach.