Sunday, June 24, 2012

For Music Gear Heads - Computer + Mainstage = Multi Effects Processor

OK - for all you musicians and computer gear heads, I thought I'd share this little tidbit of how I was able to use my computer, a firewire interface and Logic / Mainstage to create a very useful and versatile mulit-effects processor.

First, what I used:
Macbook Pro 2.4 GHz Intel Core 2 Duo processor, 4 GB Memory.
Presonus Firepod 8 X 8 firewire audio interface.
Apple's Logic software with Mainstage Version 2.1.3
Various cables to connect everything.

Hollywood at the Knotty Pine

The Problem:
The band Hollywood has been playing in the greater Cincinnati area for ever, and I've known them all for over 20 years.  GREAT group of guys who love to play 80's hair metal and are really great at it.  I've been running sound for them off and on as my schedule permits for about 7 years.  They called me on Thursday to ask if I would be available Saturday to run sound, with the caveat that the venue, "had a sound system, but no effects."  A quick visit to the venue confirmed that they indeed had no effects processors of any kind.  They have a fairly nice Allen Heath 32 channel mixer and I could use  4 aux sends for outboard effects.  Perfect...

Devising A Plan:
I do have some outboard effects modules around the house, but they are in need of repair - that's out.  But then I thought, "Mainstage has a tremendous amount of outboard processors and things I could use or this - I wonder if I couldn't use one of my Firepods as an interface and set up a Mainstage project to handle the effects.

So in Mainstage, I opened up a new project for handling Vocals or other audio signals.  I chose a blank slate so I could put together exactly what I wanted.  I created 8 mono audio channels to handle the input, then created 8 aux channels to handle the effects, and I routed the incoming signal from the incoming audio channel to the outgoing effects channel.  I then added an EQ to the mono audio channel strip to handle sound shaping, and added an effect to the aux channel strip for the effect I wanted to use.

Now, you may ask, "why didn't you just add the effect to the mono audio channel strip - you can add as many as you like?"  The answer has a bit to do with how I like to run sound, but in short, I wanted to be able to mute and unmute the incoming signal to the effect so the effect will continue to ring after I muted the incoming signal (such as a reverb or delay).  This would give me the ultimate in flexibility.

So after I selected the effects I wanted, I created a control surface in Mainstage.  This would give me control over the needed parameters throughout the night.  I simply set up a "channel strip consisting of an input meter, numerous control knobs, a fader and output meter, then a mute button.  I also created a master meter, fader and mute button, then a tap tempo button for the delay surface.  It looks like this:

The Presonus Firepods and Fireboxes are most excellent interfaces.  Great quality mike preamps and very solid processing make them a great choice for people that have computers with firewire connections.  It's sad to see firewire go away in the new Macs, but hopefully I'll be able to preserve these legacy devices because they're simply wonderful.

To connect my computer to the board, I used board aux's 1-4 and plugged them into channels 1-4 of the firepod I was connected to.  Then I used the 8 channel individual outs of the firepod to send the processed signal back to the mixing board.  It was the perfect amount of flexibility, although I could have mixed everything right from Mainstage and simply used a stereo return into the board.

I also purchased a Korg nanoKontrol some time ago for use with Mainstage, and it really came in handy for this project.  I routed all of the faders and mutes in the software control surface to the nanoKontrol, as well as routing one very important control to the pot control on the nanoKontrol.  For the reverbs, it was the reverb time.  For the delay, it was the feedback level.  For the chorus and flange, it was the speed control.

Big Verb - 20 Seconds - BOOM!
For Hollywood, I really like the flexibility of multiple reverbs.  I set up two reverbs for the drum kit - one a simple reverb that I kept between 1 and 3 seconds, then a second that I keep around 5 to 10 seconds for "cannon effects".  I assigned aux one on the mixing board to feed those two channels at the same time - I used the mute functions to switch between them.

For vocals I set up another reverb that I kept between 1-2 seconds to fill out the vocals.  I set this up on Aux 2 on the mixing board.  I have the delay coming through on Aux 3 for vocals and the odd guitar solo, using tap tempo to keep it synced with the song.  Lastly, I used Aux 4 for Chorus and / or Flange - chorus to fatten up the vocals, and flange for special effects on songs like "Electric Eye" (Judas Priest).

You knew there had to be a problem or two, but honestly it was pretty fool proof.  After getting the levels set, it was like running any other outboard gear, but with the flexibility of being able to set everything up exactly like I wanted to.  One problem I experienced was a bit of latency - about 10ms at an I/O sample size of 64 samples.  But as it turned out, it wasn't noticeable in the mix.

The other was CPU usage.  When I first started, I used the large Space Designer reverb.  With three instances of that and 6 band fully parametric on each input channel, the CPU would max out causing some harsh noises.  When I changed to Platinum Verbs and disabled 3 bands of the EQ, my CPU usage went down to around 50% - totally acceptable.

The really cool thing about Mainstage is you can create your own software control surfaces.  Having the EQ on the incoming signal really helped control some nasty frequencies that would leak through.  It meant I could get just the right sound going into the effect, so I didn't need much additional processing after the effect.

As you can see in this picture, the top 6 knobs controlled EQ functionality.  High shelf level and frequency, midrange peak (or cut) and frequency, and low shelf level and frequency.  This gave me quite a bit of control, and if I needed to adjust the "Q" or add another band, I could do that through the actual software controls.  It turns out I didn't need much of anything, which is very nice.

Next are the actual effect controls.  For the reverbs (first 3 channels, I selected a low shelf frequency to cut or boost low end through the reverb, then a wet and dry level control.  Lastly, I selected a reverb time control so I could change that on the fly.

I placed the fader and output level meter next to each other for ease of viewing on the fly.  At the bottom is a typical mute button so I could mute the incoming signal without cutting off any residual effect (reverb or delay).

So, how did it all work:
Flawlessly is the best way I could describe it!  It allowed me to have all of the effects I wanted or needed in a very nice, neat little package.  While I only used 6 effects, I had 2 spare channels ready so I could add something on the fly if necessary.  With the EQ, meters, faders and mute buttons already routed, I just needed to add some effects and select whatever controls I wanted to access through the software control surface - would take just a few minutes at most.

There you have it - I consider it a very cool success story.  :)

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