ProLogue Premium Monoblock Amplifier - $4399/pr

The critically acclaimed PrimaLuna monoblocks just got better! By incorporating the best elements of the critically-acclaimed ProLogue Six and Seven monoblocks, plus many of the ground-breaking features from the more advanced DiaLogue Series, the next generation ProLogue Premium Series, is an engineering marvel — tube monoblock amplifiers that sets a new benchmark in high-performance audio with the following features:

• Innovative, new Adaptive AutoBias circuitry. By simply flipping a switch, users can re-calibrate the amp for optimum operation of EL34s or KT88s. Every ProLogue Premium Series amplifier can be ordered with either set of power tubes installed. And remember, this circuit continuously monitors and adjusts each tube to run in its sweet spot. No biasing—ever!
• Improved output transformers designed for wide-bandwidth and high efficiency. Proprietary Custom low hum, wide bandwidth dual output transformers allow monoblocks to drive most any spaker with ease. Read the white paper here. These heavy-duty transformers elicit incredible detail from top to bottom, lower the output impedance, and provide the amp with greater control over speakers with difficult loads.
• New front-end circuitry. Optimized to use two 12AU7 tubes per channel. With the improved transformers, produces lower distortion.
• Dual feedback topology: Cross-coupled current feedback for superior impulse behavior and gain stability. Next a slight amount of negative feedback is used to achieve exact gain setting, low distortion, and low output impedance. This effectively cancels the negative byproducts associated with both feedback circuits. The end result utilizes all the benefits of feed-back, without all the drawbacks.
• Conservative design parameters: Though PrimaLuna amplifiers are powerful, tubes run well below their maxim ratings. Click here to see why.

Next, the ProLogue Premium Series introduces four innovative circuits that protect the amp at every level:

• BTI-circuit. BTI stands for "Bad Tube Indicator." On the chassis’ deck in front of each power tube, is a small LED that lights up if the tube goes bad. This circuit works hand-in-hand with the new Adaptive Auto-Bias circuit.
• PTP-circuit. If the power transformer should overheat, this "Power Transformer Protection" circuit cuts primary power, allows the amp to cool down, then resets itself.
• OTP-circuit. The "Output Transformer Protection" circuit protects the output transformers in the event of a massive tube failure or user error.
• +B relay. Replaces the plate fuse and works in conjunction with the OTP-circuit to protect the amp against tube failure. This method is less intrusive sonically and the relay resets itself once the faulty tube is replaced.

As with all PrimaLuna components, the ProLogue Premium Monoblocks are made by hand with the finest point-to-point wiring and quality equal to—or better than—any product you can buy at any price.

Built using premium parts featuring: ceramic tube sockets; Solen and Nichicon capacitors; WBT-style solid core speaker terminals; ALPS Blue Velvet volume control; gold-plated RCA jacks; toroidal power transformer. All packaged in a high-gloss, hand-rubbed finish.

Owner's manual