Product Points
Applications: Studio

Key Features: Two-channel, two inputs per channel, phantom power, phase reversal and a high-pass filter available on each channel

Price: $1,999

Contact: Trident Audio at 44-1474-815-300, Web Site; distributed in the United States by Guitar Center - 800-391-8762,


+ Two inputs per channel

+ Accepts mic or line level

+ Accepts -10 dBV and +4 dBu equipment

+ Sound quality


- Emits a substantial pop when phantom power is engaged

The Score: The Trident S20 Dual Microphone Preamp is a well-made, high-fidelity device with looks to kill.
Among the few true blue bloods in the history of audio recording is Trident. Founded in 1972 with such people as Malcolm Toft and John Oram behind the design and fabrication, you can understand why many studios relied on this sweet yet muscular console, and why the top 40 was packed with the products of those sessions. Trident Audio Development Ltd. changed hands in 1999 and was renamed Trident Audio Limited; John Oram is at the helm and has aggressively resumed manufacturing consoles and components.


The single RU Trident S20 Dual Microphone Preamplifier ($1,999) is one such example; it is the same preamp module as can be found on the Trident Series 80 console. Uniquely, there are two inputs per channel with an input selector that allows A/B switching between two microphones, a great feature for comparing which mic is really the best for that particular job. The gain knob is stepped; phase reversal and 48V phantom power buttons peek through the anodized aluminum faceplate; gain swing is from a true unity to +60 dB without any pad, allowing for use with mic and line level from both -10 dBV to +4 dBu equipment.

After the pre, a variable sweep low-cut controls from 5 Hz to 200 Hz, taking out subsonic interference. Finally, 10 bright purple, one white (at unity) and one red (overload) LEDs per channel divulge input volume. The internal power supply can be switched between 110V and 230V. Add to that a two-year warranty, and I find my salivary glands stimulated.

Under the sturdy wrap-around steel case lie sealed pots (both a blessing and a curse -dirt cannot get in as easily, but if it does it cannot be flushed out). Input jacks accept XLR and output jacks offer both XLR and TRS, all securely bolted to the back panel. Like little sentries at attention, two rows (one for each channel) of orange LEDs rise up off the circuit board and hang in mid-air. The faceplate of the preamp has a vent-like panel with a translucent sheet of white plastic behind it that diffuses the light given off by these LEDs. They glow slightly when the device is on, and light up brightly when the channel is overdriven into distortion. While functionally redundant (there is a bright red LED on the horizontal peak meter that reveals overload), as you can imagine this feature had me overloading the channel regularly just to enjoy the light show.

In Use

OK, enough about beauty; let's see if it is more than skin deep. I ran a stock U87 simultaneously through the Trident S20, a Millennia Media HV-3D, an API 512b, a Studer MicValve D19 Series, a Focusrite Red series, and just to be tough, a Telefunken V76/80 tube preamp. Since my investigation was not a shootout, I will not spend time comparing units. Self-noise of the S20 is ultralow, with the exception of a powerful pop that occurs when phantom is engaged.

My first test was on an acoustic guitar; the Trident was warm and full. I wish the high-pass filter was a semiparametric, allowing me either shelf or bell curve, but it worked well as designed. I found the low-frequency rolloff helpful for recordings that go directly into the recorder. A distinguishing feature of the Trident sound is a warm clarity without harshness, and this product holds true to that. My next test was on a snare drum, and here the mic pre really shines. It is capable of withstanding extreme transients. Pushing the preamp harder and harder until the unit went into distortion (love those orange overload LEDs!), I found the S20 had plenty of headroom. Acoustic piano was big sounding - the performer played high-register, high-volume staccato runs followed by powerful eight-note chords, and the Trident handled them both easily. On lead vocals, the Trident was warmer than the Millennia and more like the Telefunken, so Trident's boast of sounding "tube-like" is accurate.

The A/B feature (two inputs on each channel), which at first seemed like a novelty, proved to be quite useful in selecting the mics for my recording. Hooking up two brands of microphones coincidentally and being able to listen to one or the other with the flick of a switch makes the S20 an excellent evaluation tool. Yes, I know this can be done with two channels of a console, but with the S20 the signal goes through identical circuitry, making the tests more scientifically accurate.


Straight-forward engineering, coupled with John Oram's delight in designing flashy displays (the passion lights are beautiful!) makes the Trident S20 two-channel mic pre really stand out in your rack. At a mid-level price of $1,299, you are getting a real aristocrat of music history to make your own.

Review Setup

Studer D950 console; Millennia Media HV-3D, API 512b, Studer MicValve D19, Focusrite Red series, Telefunken V76/80 preamps; Genelec S30D monitors, 1094A subwoofer; Neumann U 87, TLM 170, KM 63, Shure SM58, AKG 414 EBU L, Sennheiser MKH 40, Coles 403B microphones; Mogami Neglex 2534 cables.