Our first tube preamplifier build began as many ampsandsound products do, inspired by icons. In this case, legendary line-phono units like the C22 and Marantz Model 7 guided the basic approach to the circuit. Many of these units provide controls largely abandoned by the modern audiophile - tone controls for example. These add not only additional parts, but require additional feedback to compensate for their effects, a design compromise that runs counter to our ethos.
In the style of rebuilds of tape heads as linestages, we removed these tone controls and separate out the power supplies for phono and line - there are completely separate power transformers and supplies for these two stages, something almost never seen in a unit of this type. Next we applied our attention to detail in build quality, a 200% overspecified toroidal transformer, premium 33-step attenuator volume control, high quality coupling caps, custom nickel-core step up transformers for the moving-coil input, a new custom input transformer for XLR conversion, tube rectification and application of our 10-gauge steel plate chassis, turret-board construction and fanatical attention to wiring.
All of those details are what you would expect from ampsandsound, but we also broke new ground in the design of the chassis, taking cues from 1940’s and 50’s industrial audio equipment and crafting a modular design with several distinct advantages. This new mechanical platform allows for a greater ease of repair for a complex product with multiple power supplies, and also allows for isolation between the various power supplies, volume controls and sensitive line and phono stages. It also makes room for a heavy duty, functional tube cage. The goal of permanent install industrial electronics has always been functionality and bulletproof stability. An easy demonstration of this is the Yosemite input jacks which are all panel mount, increasing reliability and ease of service. It is our aim that in 40 years a simple and easily accomplished servicing will provide an additional 40 years of service.
All of these improvements add up to one of the finest pieces we’ve ever built, and an impressive performer. The Yosemite achieves an astonishing noise figure of 23uV at -100dB, a figure which is almost unheard of for tube gear, and competes even with some solid state equipment. This is even more special when you consider that there are zero PCBs or silicone in the linestage.
Aside from excellent measurements, ampsandsound’s goal is for Yosemite to satisfy those absolute purists who must have a completely mechanical and analog device. We are never attempting to hit a sculpted sonic profile in this process and refrain from adding anything nonessential or extra, so that we may focus on the purest, simplest and best sounding path. Yosemite represents a much less colored linestage than you may expect from an old-school traditionally built pre, opting instead for wide bandwidth, depth, refinement and richness over syrupy or dark presentations. With this linestage it is our hope that you can have your cake and eat it too.