Belles LA-01 Preamplifier (HiFi-Plus 67)

Waaaaay back in the before time, in the long, long ago, Roy Gregory made a promise. Coming at the end of a review of a pair of Belles MB-200 mono amps, he said something like ‘if you think that’s good, wait until you hear the preamp’. It’s my turn to deliver the goods with the LA-01 preamp. And it is good.

Belles is one of those secret weapons in the audiophile’s arsenal. It’s not one of the superbrands, but that only means it delivers a performance you cannot easily get at the price. The designer, David Belles of Pittsford, NY, is clearly one of those no-nonsense amp designers who isn’t locked into using valves or solid-state exclusively; he goes with the device that best suits the product at the time. So the LA-01 is a completely solid-state preamp, while other devices in the portfolio take great advantage of tube performance (the same applies to the power amplifiers, although these are all solid-state – the 200 Watt mono MB-200s we used with the preamp are Class AB affairs, but there are several Class A designs too).

The preamp is a two-box, line-level affair. There are just four line-level, single-ended RCA phono inputs and a pair of single-ended RCA phono outputs. There is no phono stage. Aside from a volume control, the sole concession to flexibility is the mute control (replicated on the remote) and a 12v trigger on the back to allow the power amps to power down with the preamp. You want balance adjustment… buy another preamp. Trimmable inputs with fancy LCD readouts and home cinema by-passes are not on the Belles roadmap. You do get a multi-pin cable connecting preamp with power supply, but that’s it.

So, flexibility and a bewildering array of readouts and adjustments will never trouble the LA-01—what does it have in their place? Good, solid, no-nonsense engineering, that’s what. Like an exceptionally simple and direct signal path, combining high input impedance (100k ohms) and virtually no output impedance. That alone makes the Belles LA-01 almost textbook in terms of how a preamp should ‘see’ its sources and ‘be seen’ by power amplifiers (an ideal preamp would have infinite input impedance and zero output impedance across the frequency range); the zero crosstalk between inputs and 60dB between channels, allied to a claimed distortion figure of better than 0.001% help, too.

Belles has chosen to drive the preamp as if it were a power amplifier, using power MOSFET devices in the output stage. This means you’d really need to select a broken power amplifier, or dozens of metres of interconnect cable, to find an incompatibility between preamp and power amplifier. You could almost run a pair of speakers off the preamp on its own, because those MOSFETs run at about 10w in Class A. This is kind of why balanced operation isn’t important here, even when there’s a goodly distance between preamp and powers.

The separate power supply case sports four stages of decoupling to keep the preamp from the mains. While that is not quite a virtual battery design, it’s a very practical solution that gets close enough for most. It’s also considerably more real-world practical than going the real-battery route. There’s also a level of mechanical decoupling too, in that the chassis for both preamp and power supply (as well as many of the other amplifiers in the Belles range) sport Stillpoints feet.

‘No-nonsense design’ extends to the exterior, which is on the functional and bluff side of things. There are thick black or silver aluminium front panels and top-plates with the matching italic-script Belles logo inset in an oval, and everything is built to an exceptional standard. The three switches are tiny toggles and the volume control is distinctly ordinary. If beauty is skin deep, these things were built inside out. It’s a remarkably British design for that; nothing fancy, it’s a roll-yer-sleeves-up kind of minimalism, the sort of preamp you expect would be ‘handy’ in a fight and would even bust you a fiver for a kebab and the end of the night.

The ‘handy in a fight’ point is not just because it’s built solidly. The Belles LA-01 has a lot to commend itself in the sonics bit, as well. It manages to combine excellent solidity of sound with the sort of slippery-fast transient speed of the likes of a darTZeel. The pace is incredible; one of the many sad musical passings this year was jazz drumming legend Louie Bellson; at his peak Bellson (like Buddy Rich) played the drums with the sort of lithe expression that turned the drum kit into a fluid, legato instrument. The LA-01 has that kind of quality; dynamic classical passages hit you with an intensity that almost hurts, Gregorian chant ebbs and flows with such grace, you feel the need to burn a few witches while 50s jazz draws you inexorably toward the drummer as you hear them move around the kit.