Discontinued item listed for reference only. This is a great amplifier but just too labor intensive for us to build. We may replace it with a fully class-A dual-monoblock version; contact us if you'd be interested in such an item ([email protected]). Please read Steve Guttenberg's review on CNET and also the review by Ron Nagle in EnjoyTheMusic. Thanks! Product Brochure Owner's Manual Front Photo Top Photo Features Vacuum-tube signal path with a transistor output stage 7-tube direct-coupled design, from input stage to output High-bias class-AB output stage delivers first critical watts (up to 5W/ch, user selectable) in pure class A 140 W/ch 8 ohms | 220 W/ch 4 ohms Classic ALPS "blue-velvet" motorized potentiometer and 5 relay-selected inputs with C&K LED pushbutton switches Balanced XLR inputs offer true balanced operation with >120 dB common-mode rejection at 60Hz Cool wireless remote control; no need to point, works anywhere in the house Tempered Glass Window Massive linear (non-switching) power supplies with 108,000 uF filter capacitance and low-noise, US-made toroidal transformers 30 Amp peak output current capability 320 Volt regulated high voltage supplies operate the tubes in their most linear region Designed and made by hand in USA 6 year limited warranty Most other hybrid amplifiers are really just transistor amplifiers with a couple of tubes added in front as a preamp. The Minotaur is something different. The Minotaur is a predominantly-vacuum-tube amplifier, direct-coupled to a transistor output stage. The design uses 7 vacuum tubes to handle the input, voltage gain, and driver stages of the amplifier. The high-bias class-AB (linear, non-switching) output stage uses the well-regarded MJL3281 and MJL1302 devices in a modified Sziklai configuration for outstanding linearity, and it operates in pure class-A up to either 1W or 5 W per channel (user selectable). In developing the Minotaur, particular attention was paid both to achieving very low distortion, and also to the character of whatever small distortion was produced; at normal levels, the distortion spectrum is dominated by the single-ended 12BH7 vacuum tube driver stage and is predominantly second harmonic, like that of many musical instruments. The Minotaur is configured as a stereo integrated amplifier with five line-level analog inputs. It has 2 pairs of balanced (XLR) input connectors and 3 pairs of unbalanced (RCA) input connectors.The XLR inputs offer true balanced operation with more than 120 dB of common-mode rejection at 60 Hz. The balanced inputs can help prevent ground-loops between interconnected equipment; they can also reject common-mode digital noise from digital sources such as disk players and DACs. The Minotaur features instrument-like construction with high-quality components and connectors throughout. The vacuum tubes are powered from regulated high voltage and heater supplies to achieve minimum noise and operating drift. For user convenience, it has a wireless remote control (no need to point, works anywhere in the house), using a classic ALPS motorized potentiometer for volume control and OMRON low-signal relays for source selection. A system microcontroller monitors temperature, offset, and bias conditions to maintain optimal performance. Although the Minotaur includes a cooling fan, it should never come on in normal operation, so fan noise is not an issue. The cooling fan is included primarily to allow sustained operation at full power during testing and burn in. See the owner’s manual for more information. The Minotaur takes advantage of both the linear, high-voltage-swing capability of vacuum tubes and the high-current-delivery capability of transistors, allowing the tubes and transistors to do what each does best. And, the Minotaur is direct-coupled from the input stage to the output, avoiding the use of coupling capacitors at high-signal levels, where they can cause slow recovery from overload transients (a single coupling capacitor is used at the amplifier input, to prevent a DC offset from the signal source from being applied to the amplifier). The Minotaur is one of very few hybrids on the market to directly couple the tubes to the transistors. Each Minotaur is individually burned in and re-measured prior to shipment, and individual measurement results are included in your owner’s manual. To learn more, download a product brochure or the owner's manual, or contact us at Tavish Design ([email protected]). Parameter Specification Rated Power Output 140 W per channel continuous, both channels driven into 8Ω Power Output vs. Load Impedance 190 W per channel into 5Ω 220 W per channel into 4Ω 240 W per channel into 3Ω Output Noise < 110 uV RMS (C-weighted 30Hz - 8kHz) >108 dB below rated power Input Sensitivity and Gain +0 dBu (0.78 V RMS) for full output, 32 dB gain Total Harmonic Distortion Typically
