MicroZOTL Level 3

About the MicroZOTL Level 3

The MicroZOTL Level 3 preamplifier by Linear Tube Audio is a high-end vacuum tube preamp designed and hand-built in Maryland. It employs a non-feedback, pure Class-A design optimized for ultra-low output impedance, delivering exceptional precision and musicality. The unit 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 a headphone ¼” jack, dual RCA preamplifier outputs, and a tape monitor output. Volume control is a stepped attenuator with two settings: a default 100-step logarithmic and a high-resolution 199-step linear mode. Gain is +14dB with input sensitivity of 0.75Vrms and input impedance of 50k ohms (single-ended) or 100k ohms (balanced). The frequency response is extremely flat from 20Hz to 20kHz with minimal distortion and noise. Power output into headphones ranges from 300mW to 580mW depending on impedance. The preamp uses 2× 12AT7/ECC81 and 2× 6SN7/12SN7 tubes. Dimensions are 17" wide, 4.2" tall, and 12.4" deep, weighing 14 lbs. It includes advanced circuit optimizations such as ceramic PCBs, isolated power stages, and premium components for superior sonic performance. The Level 3 upgrade program enhances signal path, power architecture, and component quality, making it a reference-level preamplifier praised for its transparency and musical detail.