Like Bakoon's limited internal real estate particularly for a sufficiently potent yet compact and quiet power transformer, Unum's casing too is a stubborn if stylish low rider of considerable length. That not only makes for crammed innards but puts the proverbial screws on mechanical engineering to ensure adequate thermal efficiency.


That WestminsterLab's actual screws aren't ordinary types we already heard. Just like Cliff Orman of Spanish Vibex power conditioner and Kroma loudspeaker fame, the team around Angus grew hip to the undesirable side effects of conductive screws on critical component mounting. Being a brilliant dielectric of sufficient strength, polyether ether ketone aka Peek lends itself to hi-tech screwing. Unlike just screwing around, that really pays attention to the tiny details; all in the name of absolute sound quality.


What unibody milling entails is clearly visualized in the following montage which also shows a thru-hole Peek circuit board.



This layout demonstrates how an Unum casing is progressively populated with sound-producing bits.


What this nets the speculators amongst us is true RMS power of 95/190/360 monaural watts into 8/4/2Ω. Those stably double to short-term peak power of 190/380/720w respectively. -1dB bandwidth is 5Hz-75kHz, THD at 95w/8Ω remains below 1/10th a percent. S/NR is 103dB A-weighted, input impedance 200kΩ, output impedance 0.1Ω. All this packs into a 21kg case just 7.2cm tall, 23.2cm wide and 50.1cm deep. Mounting its power transistors to the metal skeleton via intermediate copper stock converts the entire affair into a thermally active dissipater. It explains why this class A/B circuit of surprising low-impedance power relative to size can be biased in class A for only half a watt. There simply isn't enough room for a larger power transformer nor can this case be overtaxed to turn into a thermal run(a)way.