THE PROCESSOR BLOCKS

There are four categories of processing in the Gold Channel — Expander/Gates, Compressors, Equalizers, and a category they call Tools.

Expander/Gates come in two flavors: the Easy Gate and the Advanced Expander. They are essentially the same processor with different controls. The Easy Gate’s controls are threshold, maximum damping (or attenuation) and mode, which is either fast or slow. No other parameters are available in the Easy Gate. The Advanced Expander has all controls available, including ratio, attack and release times, knee mode, and hold time. It also adds a bandpass filter and sidechain monitor. For cleaning up general background noise, you’ll find the Easy Gate sufficient.

There are two types of Compressors in the Gold Channel that perform in two different ways. The Soft Compressor is a typical design that compresses the signal based on the threshold setting and on the level of the input signal. The Vintage Compressor has a fixed threshold, and you adjust the Input Drive control to make the compression kick in. The result is that the Vintage Compressor is smoother than the Soft Compressor, but the Soft Compressor has more control and is capable of delivering more extreme levels of compression.

Like the Expander/Gates, there are two flavors of EQ in the Gold Channel. The Easy Equalizer is a simple five band EQ with low cut, low shelving, mid peak, high shelving and high cut bands. Gain of the low and high cut filters tops out at +/-12 dB, and the others at +/-18 dB. The Advanced Equalizer is a five band affair with low bell/shelving filters, high

bell/shelving filters, and three fully parametric filters, all with a gain of +/-18 dB. For those of you who like to tweeze your sound with EQ, the Advanced EQ has the juice to do it.

The Gold Channel’s Tools category features a number of processor blocks that just don’t fit elsewhere. Foremost among these is a proper De-Esser with a bit of a twist. The threshold is referenced to the average signal level, so the amount of de-essing stays relatively constant even when the material gets louder. Next is a Dynamic Equalizer, which is basically a de-esser with more parameters and an enlarged frequency range.

Then there is a block that TC calls a Digital Radiance Generator. This particular widget adds a bit of second order harmonic distortion to the signal. The result sounds like slightly overdriven tubes or tape saturation, and in small doses is very pleasant. It’s a little compressed and sparkly. Controls for drive (amount) and curve (tonality) are included.

Finally there’s an RIAA Playback filter for processing the direct output of a turntable and — get this — you can choose between the IEC standard from 1964 or the standard from 1987 that includes a subsonic filter! The code jockeys at TC certainly did their homework on the Gold Channel.

GOLD CHANNEL IN USE

The first assignment for the Gold Channel was to substitute it for my existing tube mic preamp. I connected a Lawson L-47MP microphone to one of the analog inputs and connected an analog output to the line input on the console. I bypassed all the processing blocks, as I wanted to hear just the mic preamp. I then read and recorded several scripts in different styles, from soft narrative to aggressive hard-sell.

The Gold Channel’s preamp is a clean accurate circuit that delivered the signal from the microphone with a minimum of coloration, and with a good frequency response. It has the character one expects from a high-quality solid-state mic preamp, which is to say very little character of its own.

Adding the Softlimiter in the preamp section did indeed squash the loudest parts a bit, but did so very gently. It’s a well-behaved limiter that does its job without being audible.

From there I began to play with the factory presets. It is clear that the folks at TC had music production in mind when they developed their presets for the Gold Channel. The first two-thirds of the one hundred factory presets have names like “Clean Guitar Fender Amp” and “Bass Amp 4X10.” But many of the other presets are named after microphones, and one supposes they’re designed for those in particular.

I recalled the “U-87 Vintage Compressor” preset and recorded the same scripts using the Lawson. This preset uses the Vintage Compressor with a fairly high 8 to 1 compression ratio, and adds a gentle EQ boost around 3 kHz and cuts everything below 80 Hz. The resulting sound had more edge, and was a bit too squashed for my taste. Lowering the compression ratio to 4 to 1 gave better results.

The unit includes some presets that are extreme — and the Gold Channel is definitely capable of creating some extreme effects. In particular, the “Voice Tweezer” preset is an effect that I found downright unpleasant. I think they were going for a telephone sound, but the result was far too bright and harsh for my taste. No matter, with a bit of EQ tweaking I fixed it right up and stored it to a user preset.

On the other hand, “Lead Vocal Chain” is an example of a complex processor configuration that sounds very good. In this preset, the output of the channel one chain is fed into channel two and processed still further. It employs a total of five processor blocks, and the resulting sound is crisp and in-your-face without being harsh.

There are also factory presets for an AKG 414 and a Shure SM-7, so I put those mics up and recorded the scripts again. Each preset worked well with its intended microphone, although the compression ratios were generally too high for my taste.

Next I tried the Gold Channel’s processing on a live recording from a rock-n-roll club. The performance was recorded in stereo to DAT and the client wanted an edited CD, so I needed to transfer the DAT to my computer for editing and mastering. I connected the Gold Channel to the DAT machine’s optical digital output and to the coaxial digital inputs of the computer’s sound card. I love having all those gozintas and gozoutas!

I auditioned several presets, and ultimately chose one called “FM Radio News” which I then tweaked. This preset exercised all the processing blocks, including the Easy Gate, Vintage Compressor, EQ, and Digital Radiance Generator. The resulting recording was far better than the original, as the processors were able to reduce the crowd noise and boost both the bass for punch and the high mids for clarity. The client was happy, and so was I.

That project also let me exercise a clever feature of the Gold Channel called Auto Gain to set the input levels. To use Auto Gain, you simply select the HEADROOM parameter in the SETUP screen, and dial in the amount of headroom you want from 0 dB to 12 dB. You then select the AUTO GAIN parameter and hit the ENTER button. The Gold Channel monitors the inputs and sets both the pad and channel gain for the maximum level, less the amount of headroom you selected. This process ensures that you get as much level as possible into the machine to utilize all the bits in the A/D converters. 

IMPRESSIONS

The Gold Channel is a very powerful voice processor. Like any power tool, it is possible to make some unpleasant noises by using its processors to excess. But used in moderation, the processor blocks sound exceedingly good and decidedly un-digital.

In particular I liked the compressors and the Digital Radiance Generator. The compressors sounded much more analog than most digital compressors I’ve used. The Digital Radiance Generator reminded me of a BBE processor, and used with discretion it added a bit of warmth and sparkle that was most pleasant.

I found it a bit difficult at times to navigate through all the options and controls in the DSP sections. I was sometimes unsure whether to grab the PARAMETER knob or the VALUE knob to tweak a function, and I often grabbed the wrong one. However, there are an amazing number of controls in the processor blocks that have to be available for tweaking, and given the limited space on the front panel I’d say TC has done a reasonable job with the user interface.

The Gold Channel is a product that screams for PC editing software. It would be really nice to be able to connect the Gold Channel to a computer and see a representation of all the processor blocks on one screen. Since the Gold Channel has MIDI, might it be possible to have such a program at some future time?

TC Electronic has done a good job of marrying their DSP expertise with a clean microphone preamp. The result is an excellent and complete microphone-to-recorder signal path. There are some distinct advantages to getting your audio into the digital domain as early as possible and keeping it there. The Gold Channel accomplishes this, and gives you a collection of useful processing tools as well.

The retail price of the Gold Channel is $2,495. For more information in the US, contact TC ELECTRONIC INC., 790-H Hampshire Road, Westlake Village, CA 91361. Phone (805) 373-1828. For more information worldwide, visit www.tcelectronic.com.