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. If anybody tells you that they have auto bias, ask them precisely how.  It's most likely not true.  As with all PrimaLuna amps, you never have to worry about biasing your amp ever again, and the need for matched tubes is eliminated.  Just plug in a myriad of different tubes including EL34, KT88, or KT120 (the cage must be left off to use KT120)  and AAB does the rest while improving sound quality.  Tubes are constantly monitored and kept in their best operating range, reducing distortion by up to 50%
  • Custom output transformers wound in house  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.
  • 2 ohm, 4 ohm, and 8 ohm taps.  All PrimaLuna monoblocks are built with the most demanding speakers in mind.  Weather you have Maggie 3.7's or Martin Logans, welcome home.  You have found an amp that will marry to virtually any speaker.  
  • 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.
  • SmartWatts design.  PrimaLuna's true-value, low stress design philosophy.  Many manufacturers fudge on their power ratings, claiming power that is mathematically impossible.  Every seasoned tube owners knows that 20 watts from a tube amp is a ton of power.  What is really important is that PrimaLuna runs their power tubes up to 40% easier that other manufacturers.  You can tell easily by putting your hand on top of a PrimaLuna amp.  They run cooler than others.  There is no reason to run tubes at their jagged edge.  Why do manufactures do it?  Click here to see why.
  • Panel mounted ceramic tube sockets and rear jacks.  Some brands will mount tube sockets or hook up jacks to a printed circuit board.  As the product ages, these boards can crack by simply changing tubes or cables.  All PrimaLuna products mount ceramic tube sockets to a stand off, and the rear panel jacks are secured directly the the chassis. 
  • Point to point wiring. The ProLogue Classic is a work of art with internal construction you won't find elsewhere.  It takes more time to build, and is assembled buy artisans, but it will last a lifetime.  

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.

All packaged in a heavy steel chassis using five coats of high-gloss, hand-rubbed finish.  Silver or black face plate available.  

Owner's manual

Specifications

Output:
70 watts x 2 with EL34 or KT88
Freq. Response: 20Hz-85kHz +/- 0.5dB
THD: Less than 1% at full power
S/N Ratio: 101 dB
Input Sensitivity: 911mV
Power Consumption (per amp): 210 watts
Dimensions: 14.5 " x 8" x 15.5" (WxHxD)
Weight (per amp): 46.3 lbs
Inputs: 1 each RCA
Outputs: 2, 4 and 8 Ohm speaker taps
Tube Compliment (per amp): 4 - 12AU7, 4 - EL34 (KT88 tubes optional)