2-Channel High-Voltage Tube Preamp
Designed with famed tube-circuit designer Anthony DeMaria, the ADL 600 employs a distinctive Class A, discrete design with three top-grade vacuum tubes per channel, operating with ±300V power rails for maximum headroom and superb tone. The dual-transformer design also ensures low-noise operation, with maximum common-mode rejection.
Only the finest components are used, including switched attenuators, analog VU and LED meters, and custom-designed, proprietary transformers. There are no op-amps or ICs in the signal path. High-end all the way, right down to the last polypropylene film capacitor.
The result is an ultra-low-noise tube preamp with a big, warm, smooth, clear, distinctive sound. It produces big, smooth, and articulate vocals; deep and tight bass guitars; and rich, full mixes. It makes virtually anything you run through it sound better.
Beyond superb sound quality, the ADL 600 is special because of its ease of use and flexibility. Each of the two input channels has a separate mic, line, and instrument inputs, and you can select among four mic-input impedances, so the preamp works great with any type of microphone.
The ADL 600’s high-pass filter employs a rotary switch with three filter settings (40 Hz, 80 Hz, and 120 Hz at 6 dB/octave) for controlling room rumble and low-frequency noise.
The input gain attenuator is a military-grade rotary switch that provides eight 5 dB stepped increments and a total preamplifier gain of over 73 dB. The output stage is controlled by a fully variable attenuator that delivers ±10 dB of fine-tuning trim adjustment, enabling you to dial in the perfect gain structure for any application. And of course, you get +48V phantom power, polarity inversion, and a 20 dB pad, controlled by big, sturdy, military-grade switches.
Fast-acting, eight-segment LED meters accurately detect fast transients and peaks. Large, backlit analog VU meters display output levels, and a -6 dB switch lets you meter particularly hot signals. Input Impedance
Microphone Selectable, 150/300/900/1500
Balanced Line 2 k
Instrument 100 k
Maximum Input Level
Microphone (1500 , +20 dB Pad out) +5 dBu
Microphone (1500 , +20 dB Pad in) +25 dBu
Balanced Line +30 dBu
Instrument +30 dBu
Microphone (1500 , +20 dB Pad out) 18 dB to 72 dB
Balanced Line -12 dB to 40 dB
Instrument -5 dB to 42 dB
Noise Floor (all inputs, minimum gain) -95 dBu (A-weighted)
Microphone Equivalent Input Noise (EIN) -125 dBu (A-weighted)
Frequency Response 10 Hz to 45 kHz ±1 dB
Maximum Output Level +23 dBu (@ 0.5%THD+N)
Output Impedance 600
Tube Complement (per channel) 1-12AT7A, 2-6922
Internal supply, standard IEC connector 115 or 230 VAC / 100W
Dimensions 2U rackmount
Height 3.5” (88.9 mm)
Depth 17" (431.8 mm)
Width 19” (482.6 mm)
Weight 28 lb. (12.7 kg)