But let’s start with the base L1 preamplifier. It could be easy to get the wrong idea about any product as upgradable as this one and assume all the steps along the way were just hobbled versions of the four-box top of the tree, and that every step just tantalises you to make the next upgrade. In fact, nothing could be further from the truth, as the solo L1 preamplifier already begins as one of the very few truly outstanding preamplifiers you can buy. It has that remarkably stark honesty and clarity of something like a passive preamplifier but with the drive and dynamic weight of a good active preamplifier. It lets the music do the talking, with no noticeable sins of omission or commission, just that sense of realising the almost unattainable goal of a ‘straight wire with gain’ in preamp form. In fact, the L1 is perhaps most surprising when compared to other preamplifiers, because in almost every case you want to say ‘other, lesserpreamplifiers’. The tiny group that can go toe-to-toe with the base L1 are among the best; c-j, Zanden, D’Agostino, Air Tight, Soulution, VTL… that sort of grade. And in most cases, the reason they sound so good is they do so little. Unlike many of the best, the CH Precision concept doesn’t include getting out a crucifix and holy water the moment someone utters the words ‘remote control’.
Also unlike most of these preamplifiers, the L1 can shift up a few gears thanks to upgrade options. The choice then becomes ‘which options?’ The first step gives the listener the choice of either adding a second L1 to make a pure monaural system or keeping the stereo preamplifier as is and adding the X1 power supply. There are those who argue for both, but I’m going with the majority and recommend the stereo+power supply over PSU-less mono version. Physically, the difference is the additional power supply takes over the power feed duties for almost all of the L1 (the existing power supply of the L1 simply feeds the logic circuit). Sonically, it extends the performance of the L1 in terms of solidity and accuracy of sound by no small margin. It essentially takes what the L1 is striving to do and make more of it in almost every respect. By way of contrast, the mono version takes what the L1 is striving to do and makes more of the soundstage alone. This creates something close to an emphasis on the soundstaging properties of the L1; in most other preamplifiers, this would seem like a triviality, but in a preamp as poised as the L1, the mono/no X1 route makes less sense than the L1+X1. That being said, in a system where soundstaging is a key function in and of itself, the paired L1’s might be the better prospect; if, for example, they were being used to control a pair of the best Stax earspeakers and energiser, or systems of that ilk.
The X1 is, in its standard guise, a single-output, ultra-low-noise, ultra-regulated DC power supply designed to drive almost every block in the CH Precision front end and control (except for the T1 clock generator for the digital audio side). As with all CH Precision products, it shares a similar casework, and the inherent modularity – coupled with a pair of really beefy transformers – makes it heavier than many power amplifiers. There is provision for an upgrade card allowing the X1 to drive two separate units, and the nature of the X1 circuit layout means if you have that card in a X1 and it cannot detect a component taking feed from it, the optional board is switched out of circuit.