I am always intrigued by Wavelength's combination of cutting-edge digital technology and tubes. Their room at RMAF featured new developments in both areas. Shown in the photo are the latest HS 24(32)/192 version of the Cosecant asynchronous USB DAC
(left, $4000), which features the new Denominator D/A module with 9016 ESS converters, and the new Royal preamp (right, $7500). Wavelength's Gordon Rankin walked me through the design of the minimalist preamp. The input signal is taken to a transformer hat inverts the polarity and feeds high-precision Penny & Giles two-channel attenuator. The wipers of the attenuator are connected directly to the grids of two 71A triodes and that's it! (The third tube is a rectifier.) Because the single tube stage inverts polarity, the preamp output is again in correct absolute polarity.