Archive for April, 2010

Using Transformers to Transform Audio

Wednesday, April 14th, 2010

This article originally appeared in Tape Op Magazine.
Technical editing by Scott Hampton

IMG_1245A transformer is a device that transfers electrical energy from one circuit to another via inductively coupled conductors – coils of insulated wire wound (most often) around a ferromagnetic core. Transformers are useful in audio recording, as they can block DC voltage and facilitate electrical isolation between gear, but they also shape the sound of signals sent through them by introducing subtle, and often very desirable “coloration”. This may be a result of any combination of frequency response, time response, distortion, or a number other factors for a particular transformer. These effects can be especially attractive when working in the digital realm, where sounds can be perceived as too “cold” or “digital”.

With all the talk of the sound of transformers, which reside in different pieces of audio gear, why not skip all the electronics and strap bare transformers into the audio path directly? The first time I heard this done was at a mastering session with Nick Blagona in Toronto, when he ran a pretty crispy sounding record through a pair of vintage Marinar transformers that he had lifted from a Neve module. The sound was just right for this record – fat lows, punchy mids and a silky top. I personally hadn’t had a chance to do much with this idea until I recently pillaged my repair guy’s stock bins, and now I’m hooked on trying all kinds of transformers in all kinds of situations.

What you’ll need are 600 ohm to 600 ohm “matching” transformers. These will generally work properly with the gear in our racks. Be careful of center tapped transformers (center tap to ground), If these are exposed to +48 volts (from phantom power) in your system they could easily be damaged. Simply wire your transformers up to cables that work with your gear or patchbay and you can insert them anywhere in your line-level signal path.

I’ve now tried transformers on all kinds of sources, and have fallen in love with many of the sounds I’m getting. My favorites so far have been a pair of vintage Triad HS-66s, as they add a mid-range thickness to the signal that really warms things up without obscuring the lows or the highs. On a full mix, they add a heft and three-dimensional quality to the sound that, while certainly not achieving the full effect, leans in the direction of a vintage console. On individual instruments they have a fattening affect that’s especially cool on kick drum and bass guitar. Pushing the signal can drive the transformer into distortion – sometimes a desirable lo-fi sound – though the need for an attenuator crops up pretty quickly. In one case I was tracking male/female duet vocals for the Brooklyn band The Loom, and found that the female singer had a strong midrange warmth that made the male voice sound a little thin in that area. By patching in one of the Triads after the compressor in his vocal chain, his sound warmed up just enough to match hers beautifully. Without disrupting the flow of the session, the transformer gave me just that little bit of harmonic complexity that I needed. It was like stirring a little more flour into the gravy, thickening to taste.

Another interesting pair of transformers were pulled from some odd quad encoder that the Japanese company Sansui was trying to develop in the ‘70s. As they were attempting to impress the pro audio market, they used some serious matching transformers. These add a harmonic richness to the midrange that can only be described as warm and fuzzy, and they also round off the highs well enough to function almost as a de-esser on certain vocals tracks. I wasn’t able to use them with any success on a mix, but on individual tracks they are able to add a strangely satisfying vibe I just couldn’t get with any other gear.

A UTC transformer that NYC engineer Matthew Agoglia liberated from a vintage compressor made a female vocal go from rich dark chocolate to three-dimensional licorice, adding a harmonic complexity that gave each syllable its own distinct vibe – way more interesting than it had been before. The same UTC on electric bass added a weight that seemed to get the signal out of the speakers and into the room, and that’s a big deal for me when working on my Pro Tools system.

IMG_1201With pairs of matching transformers slowly making their way to my studio, I’m beginning to see the possibility of putting them all in a (shielded) box, wiring them to DB-25 connectors and having them ready to be inserted between my converters and my Dangerous Audio summing box. Buying them in pairs allows me to send stereo stems out through matched left/right pairs, or to run full mixes through them. The cool thing about having multiple pairs is that you can have any number of different flavors on hand, rather than just multiples of the same sound as you would with a console. Then again, there is something to be said for the unifying effect of many of the same transformers. Experiment and see what works for you.

There are all kinds of transformers available, from vintage units by UTC, Triad, Marinar, CineMag and St Ives to brand new transformers from Carnhill, Jensen, CineMag, Lundhal, Sowter and others. While most of these companies are set up to supply gear manufacturers, I’ve found they’re all very approachable and willing to help a guy like me buy a pair. Most quality 600 ohm to 600 ohm transformers hover just above the $100 mark, so it’s a relatively inexpensive way to have some extra audio processing at hand. I highly recommend that anyone who is curious about this to try it out, and if you find some cool, obscure transformers with a vibe, do drop a line and let us know!

A Simple Transformer Explanation
A signal goes into one side of the transformer (usually the side driven is referred to as the primary), and the voltage that results on the output (secondary) is the input multiplied by the turns ratio (neglecting internal losses). The impedance ratio is the square of the turns ratio. Example: a 1:10 step-up transformer on a mic pre input would have a 1:100 impedance ratio. Meaning the voltage gain is x10, at a cost of increasing the output impedance by x100. A DI box is an example of going the other way, stepping the voltage down, to reduce the driving impedance. The lower the impedance a signal is being driven with, the less susceptible it is to noise. -SH

Review of Euphonix Artist Series Control Surfaces

Wednesday, April 14th, 2010

This review originally appeared in Tape Op Magazine.

Whether to work with a control surface or not is a personal decision. If you do prefer to have faders, knobs and buttons under hand, the one thing we will all agree on is that the integration between the surface and the software has got to be right.  Tight integration is why we still have “dedicated” control surfaces designed for specific software DAWs on the market. Euphonix, however, has developed their Artist Series control surfaces to work simultaneously with a slew of applications, even bridging between audio and visual worlds. These applications include Apogee’s Maestro for Duet, Ensemble and Symphony 64, Apple’s Final Cut Pro, Logic Pro and Soundtrack Pro, Metric Halo’s MIO Console, MOTU’s Digital Performer, Steinberg’s Cubase and Nuendo, Avid’s Pro Tools HD, LE and M-Powered, Abelton’s Live and Propellorhead’s Reason. When you think about it, this cross-platform integration really shouldn’t work, yet at the push of a button you’re working on the same surface in another program with nearly flawless integration.  For this alone Euphonix’s multiple design awards are well deserved.

The Artist Series consists of the MC Mix, the MC Control and the MC Transport, which can be used together in any combination or alone. They hitch together beautifully, creating a fully modular product line. These surfaces are so versatile that a single user’s review really can’t cover it all, and there is no way I could (or would!) ever work in enough applications and situations to fully explore the wide range of ways one might use the MC series.

With that said, I will be focusing mostly on my use of the surfaces (and particularly the MC Mix) to do stereo ixing in Pro Tools – a scenario in which I imagine many Tape Op readers also regularly find themselves.  Unfortunately, Pro Tools is the one DAW with which Euphonix has had some challenges implementing integration.  Why?  Because – and understandably so – Avid sells their own dedicated control surfaces, and the Euphonix software system, EuCon, requires that the “third party” open up their software codes for integration (aside from Live and Reason, the rest of the software developers listed above have opened their codes for integration with EuCon).  For Pro Tools integration, however, Euphonix must use the HUI protocols that Digidesign originally developed along with Mackie, and the HUI protocols have built-in limitations that make using multiple MC surfaces a little tricky.  In a nutshell, the issue is that when using more than one eight-channel MC Mix with Pro Tools, the MC Mix wont be able to splay plug-in functions out across multiple surfaces. This means that you’re limited to using one surface (typically the left-most unit) for calling up and manipulating plug-in parameters. Similarly, banking faders can be confusing when using an MC Mix and an MC Control (total of 12 faders). So, for now sticking with eight channels may be easiest for Pro Tools users, and we can only hope for better integration down the road so that it functions as seamlessly as it does with all the other programs.

Yet, even with these Pro Tools-specific limitations, I still chose the MC Mix over any other control surface in its price range. Here are the main reasons: The faders are exceptionally smooth and don’t clack and jiggle; they are the same high-resolution faders you’ll find throughout the Euphonix line.  It’s really pro stuff, and writing automation with them feels both fluid and solid like a good fader should.  The unit’s footprint is sleek, comparatively small and especially designed to work well laying on a console or between a keyboard and a monitor.  In fact, if you have Apple’s new aluminium keyboard, it’s as if they form one unit functionally and aesthetically.  Ergonomically, this integration between keyboard and surface is so much easier on my shoulders and neck over the course of a long mixing day.  The LCD screens are easy to read and don’t blind you. Once you get used to them, there’s a lot more info being fed back than you may first realize.  Another reason I chose the Euphonix surface is that if I decide to move to another DAW, the MC Mix is already integrated; I get the feeling this technology is going to be developed, not outmoded by a new model.  And, most importantly for me, this is the only control surface under $10,000.00 that allows you to select automation modes in Pro Tools without touching the mouse.

That last point is at the crux of the MC Mix and MC Control’s integration with Pro Tools because reaching for the mouse to get in and out of automation modes breaks the spell of the tactile connection to the mix.  More simply, I can keep my elbows on the desk, my head in the mix and the mouse “over there.”  Automation mode selection is especially important if you’re using the surface on top of a larger console. If you think about it, the ability to select automation modes on the Pro Tools-dedicated Icon consoles (and the Pro Control before it) is what really bridges the gap between the Pro Tools and, say, the SSL tactile experiences.  Now, for as little as a grand you can have that experience…well, almost.  The one difference is that the MC Mix doesn’t accurately display exactly which of the many Pro Tools automation modes you’re in, so you do have to look up, or over, at the screen.  It’s certainly not a deal breaker, but worth mentioning in the hope that this visual feedback will come along one day soon on these surfaces.

Working/playing on the MC Mix is intuitive, fast and fun.  I was amazed at how quickly I was moving around on it, and after about an hour I was not willing to work without it again.  The faders are easy enough to understand, yet the touch-sensitive rotary encorders at the top of the unit are where you’ll discover your inner octopus.  With just a few buttons along the left side of the unit you can shift the work these encoders do between pan, aux level, eq controls, dynamics controls, insert selection and more.  The LCDs follow the change in mode with clear visual feedback that helps you know just what you’re doing.  There is also a “channel mode” which allows you to quickly manipulate individual plug-in parameters on these knobs, and I was surprised to find how much more willing I was to automate plug-in parameters once I had tactile control.  Want to lighten up on some compression during a bombastic moment? – select your channel, enter channel mode, pick the plugin by pressing the corresponding encoder (they’re also push buttons) and there you go.  I was making this series of moves in under three seconds after just a few tries.  Want to add a little volume ride across that section, too? – select your preferred automation mode and move the fader.  You can do all of this without touching the mouse.

There are a ton of other standard features on the MC Mix that I’m assuming you’ll all expect to be there, such as solo and mute, record arm and channel select buttons.  There are also ‘select’ and ‘on’ buttons associated with each rotary encoder.  Once you get a handle on what these do, they offer up deeper levels of software control that become intuitive with use.  Like any control surface, there are also buttons for moving the faders across a session in banks or individually, but Euphonix has also built in the ability to freeze a track to a particular fader and map non-sequencial tracks to the faders.  If you’re feeling fancy, you can use time-line markers to call up different maps – something I could see film mixers using to help manage enormous track counts and elaborate mixes.

Even though I found a single MC Mix (just eight faders) to work best with Pro Tools, when I did hook up three of them together the effect was that I was suddenly sitting at a twenty-four channel console, not a string of control surfaces.  For those of you using applications that can take advantage of the EuCon software integration (see the www.euphonix.com for updated info), the temptation to link many of them together will be strong.  It’s worth noting, too, that buyng two MC Mix units gives you a sixteen-channel control surface for $2000.00, a size and price-point that’s (surprisingly) absent in the market otherwise.

The MC Control and MC Transport open up all kinds of possibilities for further configuring an interface and work-flow to suit your individual needs.  The Control is a fascinating unit that features four faders, eight assignable rotary controllers, a jog wheel and transport control, twelve programmable softkeys and a touchscreen with extremely deep programmability.  The MC Control is less about tactile control of mix functions and more about building customizable command chains (macros) that can massively speed up your workflow.  While the Control didn’t meet my needs as a mixer as much as the MC Mix (they’re well named), I was fascinated to find myself building macros that would guide me through the menus and submenus of Pro Tools with the simple tap of a button.  Those of you who do deep level editing and programming in your DAW are going to want to check out the Control right away.  It’s a deep and powerful interface that’s begging for you to design a custom workflow and leave the mouse “over there.”

The MC Transport has an enormous and very positive feeling jog wheel and outer shuttle ring, full transport and navigation controls, six assignable soft keys, timecode display and a numeric keypad.  Adding the MC Transport to either the MC Control, the MC Mix or both will allow you to nearly eradicate the mouse from your workspace.  While the ability to move through your sessions with ease is an obvious advantage, the soft keys allow you to change the functionality of the jog wheel and shuttle ring on the fly.  It’s a deceptively powerful control surface all on its own, and one that will keep many mundane editing tasks from being so thoroughly annoying.  The more you play with the MC Transport, the more you realize its flexibility.  There’s very little you can’t do with it.

What I love about Euphonix Artist Series is that it lets you decide which controls you want, how many of them and how much you want to spend.  It a truly customizable modular system, and they’ve now included the MC Color, which is designed for film colorists.  Their website has excellent information and videos to help you understand which surfaces would make the most sense for you, and if you’re considering any of these, I encourage you to spend some time watching the videos that are specific to your applications(s).  You’ll learn a lot. For those of you who use Pro Tools, do not let the current limitations of integration scare you away.  You’ll love these surfaces for their exceptionally pro feel, look, flexibility and expandability.