To maintain a family resemblance with the lower powered amplifier, the EVOLUTION 100A is housed in a similar slim case with engraved front panel and solid metal control knobs as the EVOLUTION 50A. It is available with either a Black or Silver brushed aluminium front panel and uses the same ingenious soft push button design as the EVOLUTION 50 series, offering excellent tactile feel and backlit optical indication of functions, for optimum user-friendliness. In addition to greatly increased performance, thanks to ingenious new circuit design, the EVOLUTION 100A has been equipped with 2 sets of high quality loudspeaker binding posts, with local and remote switching for A & B outputs. Optional extras include the ability to plug the Sequel mk2 Phono pre-amp inside and add the AMBIT FM/AM radio or RUBY DAC/Bluetooth/FM radio module to the expansion slot on the rear panel. After testing several methods of building a high performance and high efficiency power amplifier, suitable for this new model, David Gamble – Creek Audio’s Senior Engineer – created a unique Class G circuit especially for the EVOLUTION 100A. David chose to use four Sanken STD03 complimentary power Darlington transistors per channel, as used in the EVOLUTION 50A, which feature built-in thermal compensation. Compared to the EVOLUTION 50A, he improved the performance of the voltage gain circuitry, which, in combination with the output stage, now achieves extremely high open-loop gain and exceptionally low distortion, without sacrificing stability. The result is an exceptional power amplifier circuit with very low output impedance and high output current capability. This combination provides exceptional speed and control suitable for driving most loudspeakers. To increase the power output of the smaller EVOLUTION 50A, yet still retain the same case size, David Gamble developed a cunning Class G circuit which runs normally at a lower voltage for power levels up to 25 Watts into 8 Ohms. When required to produce more than 25 Watts, the amp automatically swings to a higher secondary voltage, to increase the output power capability to over 100 Watts into 8 Ohms. It is a modern listening trend for headphones to now be fed from low voltage sources, such as smart-phones and portable music storage devices. This required the development of low impedance headphones, to draw the required current to make them loud enough to satisfy the consumer. This trend has also necessitated a re-think of circuitry used in modern Hi-Fi amplifiers, to drive such low impedance headphones, together with the traditional medium to high impedance versions also. Creek Audio has taken the unusual step of driving the headphone output socket of their EVOLUTION amplifiers from a dedicated low impedance source. Instead of the headphone output being sourced from the power amplifier, the headphone output is derived from a dedicated amplifier, with only a few Ohms in series for protection against short circuits. This dedicated HP amp is now located on the pre-amplifier circuit board. For vinyl fans, the EVOLUTION 100A can also be configured for Vinyl Disc input, using Line input 1. A SEQUEL 2 (40, 48 or 54) module can be plugged into a dedicated connector on the pre-amp PCB. It doesn’t restrict the use of either the AMBIT or RUBY modules. Sequel 2 comes in three versions – 40dB MM, 48dB MC and 54dB MC. The EVOLUTION 100A is the most sophisticated and reasonably priced amplifier Creek has ever made. It provides stunning audio performance and is capable of out-performing other makes of amplifiers costing many times the price.