Anthony DeMaria Labs ADL-600 is a dual-channel, high-voltage valve microphone preamplifier designed without compromise, built around extreme operating voltages, discrete Class A circuitry, and large custom transformers. Running on ±300 V power rails, the ADL-600 operates at voltages far beyond conventional op-amp based designs, delivering exceptional headroom, extended low-frequency depth, smooth high-frequency detail, and a rich, authoritative overall character that defines the unit’s sonic identity.
The signal path is entirely free of integrated circuits, relying instead on genuine discrete transistors, resistors, and capacitors selected for ultra-low noise and transparency. This design philosophy eliminates the added noise, coloration, and hardness often associated with op-amps, allowing the ADL-600 to remain open, detailed, and natural across a wide dynamic range. The Class A output stage remains fully biased at all times, ensuring linear operation with no crossover distortion and consistently musical results.
Central to the Anthony DeMaria Labs ADL-600 sound are its large, high-quality, custom-wound, shielded input and output transformers. The Cinemag input transformer defines the preamp’s linear, detailed response and forms the foundation of the entire amplification stage. The nickel and iron core output transformer provides exceptional headroom and introduces gentle, musically pleasing saturation at very high levels, adding depth and finish without obscuring detail. Together, these transformers also isolate the preamp from connected microphones and downstream equipment, a critical consideration in a high-voltage valve design.
Beyond its sonic performance, the Anthony DeMaria Labs ADL-600 offers exceptional flexibility and ease of use. Each of the two channels provides dedicated microphone, line, and instrument inputs, along with selectable microphone input impedances that allow optimal matching with any microphone type. A stepped gain control, variable high-pass filter, output trim, and comprehensive metering ensure precise control in both recording and mixing environments, making the Anthony DeMaria Labs ADL-600 suitable for everything from delicate acoustic sources to high-level line signals.
Features
- Mic, line, and instrument inputs on each channel
- High-voltage Class A vacuum-tube signal path
- Dual-channel design with custom input and output transformers
- Three military-grade vacuum tubes per channel
- Selectable microphone input impedance
- Variable high-pass filter
- Stepped gain control with output trim
- 48 V phantom power
- -20 dB pad and polarity reverse
- Backlit VU meter with -6 dB range switch
- More than 73 dB of total gain