Recording - September 2015 - 38

The test
I made a bunch of 16-track mixes and then recorded the output
of each individual box (with all the knobs set to 0 dB, if the unit had
knobs), as well as the output of Pro Tools | HDX, the output of Pro
Tools on my laptop, and the output of the Harrison console (with all
the faders set to unity as well). Interestingly the output of the console was consistently louder than that of the other units. Although
that might be a nice side effect of a real analog console, I wanted
to make sure we weren't going to misinterpret loudness for quality.
I calibrated all the outputs to make sure the playback levels of our
six recordings were as close to each other as possible.

I was interested in hearing a second opinion, so I invited a
bunch of well-respected colleagues to the studio to participate in
the test. In the end it was only me with Pete Auslan, engineer for
Diana Ross, carefully listening to the same recordings over and
over and over again, discussing differences, comparing small
bits of audio, calibrating levels, etc. Thanks, Pete!
We found that the shorter the loop, the easier it was to focus on
the sound, or at least on a part of the full spectrum of the sound.
For example, we looped 2 bars of a drum beat so that we could
just focus on the kick and the snare and the hi-hat-high end on
the hat, attack and low end of the kick, or the body of the snare.
The results are remarkably close and the differences are very
subtle, more so than I thought-which shows not only that the
gap between analog and digital has narrowed significantly, but
more importantly that trained ears make a far greater difference
than gear in creating a great mix!

Listen for yourself
You can download the audio files from www.marcurselli.com/
SummingTests.zip and listen for yourself. This 403 MB ZIP file contains 24-bit/88.2 kHz audio files named with the following numbers:
1. In-the-box summing with Avid Pro Tools | HDX (avid.com)
2. Harrison Series 10B analog console, the one at EastSide
Sound Studios where I did the tests (harrisonconsoles.com)
3. Dangerous Music 2-Bus LT (dangerousmusic.com)
4. SSL Sigma (solidstatelogic.com)
5. Rupert Neve Design 5059 Satellite (rupertneve.com)
6. In-the-box summing with Avid Pro Tools Native

38

RECORDING September 2015

The source material includes Drums, Drums/Bass/Guitar,
Drums/Bass/Guitar/Keys, and Piano/Strings/Reeds, so you
can listen to a variety of sources. You will find the files inside the
"Audio Files" subfolder.
For those of you who have Pro Tools I have also included files for
Pro Tools 7-9 (.ptf extension) and Pro Tools 10-12 (.ptx extension).
When you open these, the audio files will be lined up properly so
that you can scroll through loops and really focus on the subtle differences between these files. If you are a Pro Tools user, I recommend
you set Pro Tools in Loop Playback and then use the Solo In Place
function so that you can loop through a recording or just a loop and
jump from one track to the other without audio interruption. To do that
on Pro Tools, select Options Menu > Loop Playback and then select
Options Menu > Solo Mode > X-OR (Cancels Previous Solo).

Dangerous 2-BUS LT
The Dangerous 2-BUS LT ($1499 street price) is a 16-channel
summing amp with no trims or pan pots, which I think is really
what a summing amplifier should be. This avoids redundant
audio circuitry and gives you the ability to recall your mixes
without un-storable settings to remember. You can use this box
as a 16-channel summing amp in mono, but mix engineers will

want to use it as an 8-channel stereo unit with panning performed within the DAW. You can expand your track count by
daisychaining multiple units. The non-LT version of this box
(which I did not test) has a +6 dB boost and stepped output
attenuators, and earlier this summer Dangerous announced the
2-BUS+ with even more features.
What this unit lacks in features, it makes up in sound. Punch
and detail are what the manufacturer boasts about, but in this
case it isn't just marketing talk, they really deliver that! Out of the
three units I tested, the Dangerous at times offered a slightly more
defined low end. My only gripe: the 2-BUS LT is the only one of
the three units I tested that fits in one rackspace (1U), which saves
space but relies on an external power supply with a flimsy-feeling 5-pin DIN connector, as opposed to the much sturdier screwon 7-pin connector for the 2U non-LT version of the 2-BUS.

Rupert Neve Designs 5059 Satellite
The Rupert Neve Designs 5059 Satellite ($3749 street price)
uses a slightly different approach. This made-in-the-USA 2U unit
has level and pan knobs and even insert capabilities for every
one of its 16 channels, which also lets it serve as a high-end line
mixer. That's handy for some users, but if you are strictly using
it as a summing amplifier, you'll have to leave the pan pots set
to hard left/right and the level trims at 0 dB. The latter is a bit
annoying, as the trims go from silence to +10 dB but have no
detent at unity gain or bypass function. That makes it difficult to
set up and recall 100% accurate track levels... unless you never,
ever touch the trim knobs!
http://www.marcurselli.com/SummingTests.zip http://www.marcurselli.com/SummingTests.zip http://www.avid.com http://www.harrisonconsoles.com http://www.dangerousmusic.com http://www.solidstatelogic.com http://www.rupertneve.com
Table of Contents for the Digital Edition of Recording - September 2015
