The popularity of the Masterclass series has resulted in over seventeen years of continuous production. Offering an excellent price/performance ratio it is easy to see why it remains so successful. With an abundance of headroom, the MPA-4 mono power amplifiers deal easily with heavy complex music, allowing the low level detail to be heard clearly and accurately. Boasting a fully balanced circuit design, it can be the engine room of a fully balanced hi fi system.

The SPA-4 is a stereo version of the MPA-4 and uses the same class A circuit. The only differences are power output and the additional flexibility of both single ended and balanced inputs. Not every music lover can accommodate two substantial power amplifiers in their listen space, so a single SPA-4 could be the solution. One of the noticeable abilities of the SPA-4 is how well it works with smaller loudspeaker designs as well as large ones. Control and soundstage are two key elements of the SPA-4 making it a fine power amplifier.

 High-end touches include gold plated circuit boards, relay switching of all inputs and output and a sophisticated class A output stage. The LA-4 is a high gain amplifier that provides an iron fist of control over any power amplifier.  The electronic circuitry has been developed to offer the best possible sonic performance without compromise including the use of specially selected transistors and capacitors to provide the best signal preservation.  The gain stages are each powered by current shunt differential power supplies, which enable the fastest transients and most powerful crescendos with true musical empathy.