Chandler Limited TG2 Microphone Pre-Amp by: Barry Rudolph
EQ Issue #2, 2003
Introduction
The single rack space TG2 microphone preamp uses the same circuit design and components of the TG12428 amplifier from EMI's TG Series mixing and mastering consoles. The 1970's TG Series was EMI's first transistorized equipment designed to replace their tube gear in use since the 1950's. Although the TG desk was used for The Beatles' Abbey Road, many other seminal records of the early seventies through 1983 were recorded on TGs including Pink Floyds' Dark Side of the Moon.
The two-channel TG2 is hand-made in the USA and features an all-discrete Class-AB circuit with balanced transformer inputs and outputs. The Carnhill/St. Ives microphone input and output transformers, like most of the TG2's components, are made in England. Typical of the entire Chandler Limited product line, the TG2 is beautifully crafted in a rugged nickel-plated steel box ready for the road or studio. The hand-soldered Elma controls and switches are mounted to an internal frame (not directly on the front panel) and handsomely wired to two, solidly mounted circuit boards. The half-rack space PSU-1 external power supply powers up to two TG2 units.
Unique Sound Quality
As "homage" to a bygone era, the two-channel TG2 doesn't disappoint with a wide-open sound mostly due to the same "tailored" frequency response found on original TG Series gear. A kind of "personality", the preamplifier's frequency response curve is flat from 20Hz to 3kHz and then slowly begins rising for a very subtle boost of 1.5dB by 16kHz. I found the preamp's sound quality somewhere between an API 512 mic preamp and Neve's 1272 amplifier as used in the 1073/1084 modules. You'll find a whole new sonic world here: higher dynamic range than the Neve combined with API's "harder, punchier" sound character. The TG2 has a more desirable gain selection range than either Neve or API with a fifteen-position gain switch starting at 5dB and going up to 75dB in 5dB repeatable steps. This update of the original TG circuit is perfect for accommodating modern condensers that have higher output levels than older mics. Vintage pre-amps (generally) start with more gain at their lowest setting (both Neve and API modules start with 20dB of gain) sometimes necessitating use of the mic's pad when close-miking loud sources.
The Output control is before the final output stage circuit and acts as a fine gain adjust. Both the Gain and Output knobs are old-fashion black radio pointer knobs that fit the vintage British battleship gray front panel. The TG2's mic input is able to accept line levels allowing for interesting overloading and coloration treatments by cranking up the Gain control and turning down the Output--like using a guitar amp with a master volume control. All fun, this effect on a vocal track sounds a little like John Lennon singing "Polythene Pam" with loads of third harmonic fizz.
Microphone input impedance is 1200 ohms and the review unit has an additional unmarked switch that changes the input impedance to 300 ohm--a $150 option I recommend ordering. Front panel locking Neutrik 1/4-inch, 100k impedance input jacks are provided for direct instrument recording. I liked that the DI switch toggles between the rear panel mic XLR and front panel DI jack. If you don't use the DI, then the switch works as a mute button--good idea! The unit also has phase reverse and +48volt phantom on/off switches. I'd like to see an output clip LED and phantom power on/off indicator on the front panel.
In The Studio
I first tried the TG2 for recording acoustic guitars for both strumming and fingerpicking parts. I used a Swedish Milab DC 96B cardioid condenser, an API 550B equalizer (also Class-AB design) followed by an 1176LN limiter. This signal chain produces an aggressive acoustic rock sound and I found the TG2 very quiet with more than enough gain. I also ended up NOT using the equalizer because proper mic positioning and the open sound of the TG2 was all I required. For an inveterate knob tweaker like me, I loved that rotating the gain switch produce no clicks or pops--even with audio present. I did discover that the PSU-1 power supply (as well as some other gear) must be located well away from the preamp chassis otherwise noise and hum was introduced into the audio.
Next came vocals with the TG2 again providing clear and accurate sounding preamplification. Unlike the Neve 1084 module I had used the night before, there was no "collapse" or preamplifier compression or distortion on peaks when my singer sang loudly into an Rode NTK condenser mic. I also didn't feel a big need to equalize and the smooth output control was perfect for riding down loud vocal moments to avoid over-squashing by the following TubeTech CL-1A compressor.