Chandler EMI TG12413 Zener Limiter
by: Mike Caffrey, www.monsterisland.com
Tape OP, Issue #59, May/June 2007

From micro-limiting to full-on annihilation, the TG12413 has the controls to finesse the sound as precisely as you can hear it, while your signal runs through a classic circuit which sounds the way people hope for when they use the words “vintage” and “warm.” If your music store salesman says, “Dude, this one sounds fat and warm,” he’ll actually be right for a change.

The TG12413 is based on the same circuit as the now familiar Chandler TG1 Abbey Road Special Edition Compressor/Limiter, which is phenomenal sounding and capable of making many unique and beautiful sounds. Because this is now a fairly well-known sound, I spent a lot of time A/B’ing the two to see how different the TG12413 is. Beyond a slightly different tone, the TG12413 has additional input controls, an additional compression mode, expanded attack/release times, and an adjustable internal side chain filter for the detector.

In order to compare the tones of the TG12413 and TG1, I set them both to THD mode, which passes the audio signal through the compressor circuit but disables the gain reduction, so you get the tone of the device without any compression. I balanced them with an oscillator to be sure the comparison was not influenced by mismatched levels. After listening back and forth just a couple of times, it was very easy to tell the two apart. The TG1 had a more saturated tone and a little more low end. When A/B’ing them with gain reduction in, using Limit mode on the fastest attack and release settings (a sound that the TG1 is known for), there was a clear difference in how the low end harmonics distorted. When running a finished mix through the two (which is not something I’d normally compress this way) the TG12413 had a little buzzy tone at the top of the low end. It didn’t distort as smoothly as the TG1. An analogy would be along the lines of the way a Fender or a VOX amp might distort compared to a Triple Rectifier, with the TG12413 being the Fender/VOX and the TG1 being the Triple Rec. The differences were smaller when I slowed the release time on the TG12413 from 1 to (1). The TG12413 has a color-coded labeling system with white labels designating settings identical to a vintage TG unit and yellow designating new selections chosen by designer Wade Goeke. The release times in parenthesis are part of this labeling system and match the six release times of the TG1. The TG12413 has two release times that are faster than the TG1, which are mainly meant for use in the two compression modes. Switching from release 1 to release (1) made the settings the same.

I’ve been using two TG1s for several years, and they have been an important part of my drum sound since day one. One is always in Limit mode on the drum room mics with the fastest release setting. I’ve also used them when I wanted an aggressive, in-your-face vocal sound; a dead-even leveling for a background vocal subgroup; room reverberance on guitars; a tight, thick electric guitar sound; and in some cases on the stereo mix. The TG12413 does the same thing in all of these applications. Recently, I did a mix where I used the TG12413 on a string subgroup. What sets the TG12413 apart from the TG1 is its ability to do less.

Because the TG1 has no attack control, there are times when a particular release time makes the compression sound too hyped (as can happen with any compressor set incorrectly). But if you slow the release down, it holds too long and sounds wrong too. Because the input affects both the amount of gain reduction and harmonic distortion, cutting back on the compression may change the tone too much. The TG12413 opens up a new world of detail and finesse with the addition of the attack control. Now, if necessary, you can reduce the too-hyped sound by slowing down the attack without changing the input level, and you don’t lose the tone you’re getting from the harmonic distortion you’re adding at the input stage.

There are two more new controls that are key: the input impedance switch, and the internal side chain. Because of the great tone and vibe the TG1 is capable of, I often find myself wanting to use it on the stereo bus, but as it’s a monster compressor, sometimes it’s too much. The TG12413’s impedance switch allows you to knock 12 dB off the input, allowing the TG12413 to work in applications where the TG1 would be too much. This is when the TG12413 benefits from having less saturation and low-end boost than the TG1, because the TG12413’s ability to be more subtle makes it a much better choice for the stereo bus. The other key control is the internal side chain’s High Pass Filter for the level detector. You sometimes see this labeled as a “big” switch on other compressors, but I’ve never seen one with selectable frequencies. By reducing the gain reductions caused by low frequencies, you’ve got yet another way to get more subtle or precise. One great use for this is to reduce cymbal splashiness when crushing drums room mics. Sometimes, the drums sound amazing but when the drummer starts hitting the cymbals (and they so rarely balance them properly with the rest of the kit), the cymbal ring starts going “pwisssshhh pwisssshh pwisssshhh” when the drums hit, making the sound unbearable. The dilemma is, if you reduce the compression, you kill the great drum sound. In a lot of cases, it’s the kick drum that’s triggering the detector and causing the splashy cymbal sound. Cranking the side chain filter up to 90, 150 or even 300 Hz can cut the splash to acceptable levels.

In a sense, the best way to describe the TG12413 is, “Just like a TG1, and less.” The TG12413’s extra controls allow you to play in the areas of less compression. The additional compression mode (Comp 2) gives you settings in-between Comp 1, which has the 2:1 ratio of the original EMI TG12413, and the super aggressive Limit setting.

As I became aware of how much subtlety the TG12413 is capable of, I started playing with what I think of as micro-limiting—getting just that little bounce at the edge of no gain reduction. Certainly, adding a lot of punch and attack through a lot of gain reduction or a big explosive release is a fun way to use a compressor, but when you have a cool vintage tone to work with, there’s a whole very cool world where you have just some tiny pumping—the meters just bouncing in time with the track so that they move as far as a quarter bouncing on a tabletop that’s being rocked by a subwoofer. Ironically, although the TG12413 is vintage-style piece, you could argue that LED meters would be a better choice since the ballistics of the needles in a VU meter simply can’t accurately represent attack and release times of 5, 8, or 10 ms. So keep in mind that you may be compressing quite a bit more than you think you are when you see the needles showing only a half dB of gain reduction. When you read interviews about compression, people tend to talk about the extreme stuff the most because it sounds cool. “I love to smash the room mics.” Or, “I hit the tape really hard.” But often, when you hear an amazing sounding mix, it’s the result of a lot of subtle detail work. It may seem counterintuitive that a big and powerful mix might come from something gentle, but too much compression makes things small. You don’t often read comments like, “I just used a little compression on the last 311 album,” yet Ron St. Germain hates compression. If you do a Google search for “Kissing the Focusrite,” you’ll find a Chris Lord-Alge interview. Or from Michael Brauer, you’ll hear the phrase “A lot of compressors, but not a lot of compression.” The TG12413 is capable of this level of finesse with the tone you’re used to hearing from the TG1.

It’s really kind of superficial to talk about how something looks, but at 3RU height and with cool red and black VU meters, the TG12413 will stand out in any rack. And unlike some of the artists you’ll run through it who struggle to sound as good as they look, the TG12413 sounds great. I can only imagine how happy EMI must be to have Wade Goeke designing the gear that their name goes on. I bet his birthday will soon be a company holiday, and they’ll be taking out a massive insurance policy on his ears, because he keeps nailing it, design after design.

—Mike Caffrey