MicroZOTL

About the MicroZOTL

The MicroZOTL preamplifier is a reference-grade line-level preamplifier originally designed by David Berning and later produced by Linear Tube Audio. It employs a unique push-pull Class A, no feedback circuit topology using vacuum tubes (two 12AT7/ECC81 and two 6SN7/12SN7 tubes) and ZOTL technology to achieve extremely low output impedance (around 2 ohms) and high linearity without the use of output transformers. The preamp features 4 stereo RCA single-ended inputs with high-quality Cardas connectors, one XLR transformer-coupled balanced input with Lundahl transformers, and a tape input. Outputs include dual RCA single-ended preamplifier outputs, a tape monitor output, and a headphone 1/4" jack. Volume control is implemented via a stepped attenuator with up to 199 steps for fine resolution. The unit is housed in an aluminum case with dimensions approximately 17" wide, 4.2" tall, and 12.4" deep, weighing about 14 lbs. It operates on user-selectable 115VAC or 230VAC power and consumes about 50W. The MicroZOTL is praised for its musicality, precision, and ability to drive headphones and high-efficiency speakers with excellent tonal accuracy and low noise floor. It is considered a unique and highly regarded design in the audiophile community, offering a distinct sound experience without the compromises of traditional transformer-coupled tube preamps.